From: Jens Axboe Date: Mon, 27 Feb 2006 15:37:08 +0000 (+0100) Subject: [PATCH] kernel: update kernel patch to include Toms read/sendfile consolidation X-Git-Tag: blktrace-0.99.2~57 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=c135da93c5e0e0829234ba2070f6612260ca82c2;p=blktrace.git [PATCH] kernel: update kernel patch to include Toms read/sendfile consolidation --- diff --git a/kernel/blk-trace-2.6.16-rc5-git-A0 b/kernel/blk-trace-2.6.16-rc5-git-A0 deleted file mode 100644 index c7e5ee0..0000000 --- a/kernel/blk-trace-2.6.16-rc5-git-A0 +++ /dev/null @@ -1,4168 +0,0 @@ -diff --git a/block/Kconfig b/block/Kconfig -index 377f6dd..9678364 100644 ---- a/block/Kconfig -+++ b/block/Kconfig -@@ -11,4 +11,16 @@ config LBD - your machine, or if you want to have a raid or loopback device - bigger than 2TB. Otherwise say N. - -+config BLK_DEV_IO_TRACE -+ bool "Support for tracing block io actions" -+ select RELAY -+ select DEBUG_FS -+ help -+ Say Y here, if you want to be able to trace the block layer actions -+ on a given queue. Tracing allows you to see any traffic happening -+ on a block device queue. For more information (and the user space -+ support tools needed), fetch the blktrace app from: -+ -+ git://brick.kernel.dk/data/git/blktrace.git -+ - source block/Kconfig.iosched -diff --git a/block/Makefile b/block/Makefile -index 7e4f93e..c05de0e 100644 ---- a/block/Makefile -+++ b/block/Makefile -@@ -8,3 +8,5 @@ obj-$(CONFIG_IOSCHED_NOOP) += noop-iosch - obj-$(CONFIG_IOSCHED_AS) += as-iosched.o - obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o - obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o -+ -+obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o -diff --git a/block/blktrace.c b/block/blktrace.c -new file mode 100644 -index 0000000..7c9ac33 ---- /dev/null -+++ b/block/blktrace.c -@@ -0,0 +1,533 @@ -+/* -+ * Copyright (C) 2006 Jens Axboe -+ * -+ * This program is free software; you can redistribute it and/or modify -+ * it under the terms of the GNU General Public License version 2 as -+ * published by the Free Software Foundation. -+ * -+ * This program is distributed in the hope that it will be useful, -+ * but WITHOUT ANY WARRANTY; without even the implied warranty of -+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -+ * GNU General Public License for more details. -+ * -+ * You should have received a copy of the GNU General Public License -+ * along with this program; if not, write to the Free Software -+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA -+ * -+ */ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; -+static unsigned int blktrace_seq __read_mostly = 1; -+ -+/* -+ * Send out a notify for this process, if we haven't done so since a trace -+ * started -+ */ -+static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) -+{ -+ struct blk_io_trace *t; -+ -+ t = relay_reserve(bt->rchan, sizeof(*t) + sizeof(tsk->comm)); -+ if (t) { -+ t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; -+ t->device = bt->dev; -+ t->action = BLK_TC_ACT(BLK_TC_NOTIFY); -+ t->pid = tsk->pid; -+ t->cpu = smp_processor_id(); -+ t->pdu_len = sizeof(tsk->comm); -+ memcpy((void *) t + sizeof(*t), tsk->comm, t->pdu_len); -+ tsk->btrace_seq = blktrace_seq; -+ } -+} -+ -+static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, -+ pid_t pid) -+{ -+ if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) -+ return 1; -+ if (sector < bt->start_lba || sector > bt->end_lba) -+ return 1; -+ if (bt->pid && pid != bt->pid) -+ return 1; -+ -+ return 0; -+} -+ -+/* -+ * Data direction bit lookup -+ */ -+static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; -+ -+/* -+ * Bio action bits of interest -+ */ -+static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC) }; -+ -+/* -+ * More could be added as needed, taking care to increment the decrementer -+ * to get correct indexing -+ */ -+#define trace_barrier_bit(rw) \ -+ (((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0)) -+#define trace_sync_bit(rw) \ -+ (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1)) -+ -+/* -+ * The worker for the various blk_add_trace*() types. Fills out a -+ * blk_io_trace structure and places it in a per-cpu subbuffer. -+ */ -+void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, -+ int rw, u32 what, int error, int pdu_len, void *pdu_data) -+{ -+ struct task_struct *tsk = current; -+ struct blk_io_trace *t; -+ unsigned long flags; -+ unsigned long *sequence; -+ pid_t pid; -+ int cpu; -+ -+ if (unlikely(bt->trace_state != Blktrace_running)) -+ return; -+ -+ what |= ddir_act[rw & WRITE]; -+ what |= bio_act[trace_barrier_bit(rw)]; -+ what |= bio_act[trace_sync_bit(rw)]; -+ -+ pid = tsk->pid; -+ if (unlikely(act_log_check(bt, what, sector, pid))) -+ return; -+ -+ /* -+ * A word about the locking here - we disable interrupts to reserve -+ * some space in the relay per-cpu buffer, to prevent an irq -+ * from coming in and stepping on our toes. Once reserved, it's -+ * enough to get preemption disabled to prevent read of this data -+ * before we are through filling it. get_cpu()/put_cpu() does this -+ * for us -+ */ -+ local_irq_save(flags); -+ -+ if (unlikely(tsk->btrace_seq != blktrace_seq)) -+ trace_note_tsk(bt, tsk); -+ -+ t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); -+ if (t) { -+ cpu = smp_processor_id(); -+ sequence = per_cpu_ptr(bt->sequence, cpu); -+ -+ t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; -+ t->sequence = ++(*sequence); -+ t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); -+ t->sector = sector; -+ t->bytes = bytes; -+ t->action = what; -+ t->pid = pid; -+ t->device = bt->dev; -+ t->cpu = cpu; -+ t->error = error; -+ t->pdu_len = pdu_len; -+ -+ if (pdu_len) -+ memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); -+ } -+ -+ local_irq_restore(flags); -+} -+ -+EXPORT_SYMBOL_GPL(__blk_add_trace); -+ -+static struct dentry *blk_tree_root; -+static struct mutex blk_tree_mutex; -+ -+static inline void blk_remove_root(void) -+{ -+ if (blk_tree_root) { -+ debugfs_remove(blk_tree_root); -+ blk_tree_root = NULL; -+ } -+} -+ -+static void blk_remove_tree(struct dentry *dir) -+{ -+ mutex_lock(&blk_tree_mutex); -+ debugfs_remove(dir); -+ blk_remove_root(); -+ mutex_unlock(&blk_tree_mutex); -+} -+ -+static struct dentry *blk_create_tree(const char *blk_name) -+{ -+ struct dentry *dir = NULL; -+ -+ mutex_lock(&blk_tree_mutex); -+ -+ if (!blk_tree_root) { -+ blk_tree_root = debugfs_create_dir("block", NULL); -+ if (!blk_tree_root) -+ goto err; -+ } -+ -+ dir = debugfs_create_dir(blk_name, blk_tree_root); -+ if (!dir) -+ blk_remove_root(); -+ -+err: -+ mutex_unlock(&blk_tree_mutex); -+ return dir; -+} -+ -+static void blk_trace_cleanup(struct blk_trace *bt) -+{ -+ relay_close(bt->rchan); -+ debugfs_remove(bt->dropped_file); -+ blk_remove_tree(bt->dir); -+ free_percpu(bt->sequence); -+ kfree(bt); -+} -+ -+static int blk_trace_remove(request_queue_t *q) -+{ -+ struct blk_trace *bt; -+ -+ bt = xchg(&q->blk_trace, NULL); -+ if (!bt) -+ return -EINVAL; -+ -+ if (bt->trace_state == Blktrace_setup || -+ bt->trace_state == Blktrace_stopped) -+ blk_trace_cleanup(bt); -+ -+ return 0; -+} -+ -+static int blk_dropped_open(struct inode *inode, struct file *filp) -+{ -+ filp->private_data = inode->u.generic_ip; -+ -+ return 0; -+} -+ -+static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, -+ size_t count, loff_t *ppos) -+{ -+ struct blk_trace *bt = filp->private_data; -+ char buf[16]; -+ -+ snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); -+ -+ return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); -+} -+ -+static struct file_operations blk_dropped_fops = { -+ .owner = THIS_MODULE, -+ .open = blk_dropped_open, -+ .read = blk_dropped_read, -+}; -+ -+/* -+ * Keep track of how many times we encountered a full subbuffer, to aid -+ * the user space app in telling how many lost events there were. -+ */ -+static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, -+ void *prev_subbuf, size_t prev_padding) -+{ -+ struct blk_trace *bt; -+ -+ if (!relay_buf_full(buf)) -+ return 1; -+ -+ bt = buf->chan->private_data; -+ atomic_inc(&bt->dropped); -+ return 0; -+} -+ -+static int blk_remove_buf_file_callback(struct dentry *dentry) -+{ -+ debugfs_remove(dentry); -+ return 0; -+} -+ -+static struct dentry *blk_create_buf_file_callback(const char *filename, -+ struct dentry *parent, -+ int mode, -+ struct rchan_buf *buf, -+ int *is_global) -+{ -+ return debugfs_create_file(filename, mode, parent, buf, -+ &relay_file_operations); -+} -+ -+static struct rchan_callbacks blk_relay_callbacks = { -+ .subbuf_start = blk_subbuf_start_callback, -+ .create_buf_file = blk_create_buf_file_callback, -+ .remove_buf_file = blk_remove_buf_file_callback, -+}; -+ -+/* -+ * Setup everything required to start tracing -+ */ -+static int blk_trace_setup(request_queue_t *q, struct block_device *bdev, -+ char __user *arg) -+{ -+ struct blk_user_trace_setup buts; -+ struct blk_trace *old_bt, *bt = NULL; -+ struct dentry *dir = NULL; -+ char b[BDEVNAME_SIZE]; -+ int ret, i; -+ -+ if (copy_from_user(&buts, arg, sizeof(buts))) -+ return -EFAULT; -+ -+ if (!buts.buf_size || !buts.buf_nr) -+ return -EINVAL; -+ -+ strcpy(buts.name, bdevname(bdev, b)); -+ -+ /* -+ * some device names have larger paths - convert the slashes -+ * to underscores for this to work as expected -+ */ -+ for (i = 0; i < strlen(buts.name); i++) -+ if (buts.name[i] == '/') -+ buts.name[i] = '_'; -+ -+ if (copy_to_user(arg, &buts, sizeof(buts))) -+ return -EFAULT; -+ -+ ret = -ENOMEM; -+ bt = kzalloc(sizeof(*bt), GFP_KERNEL); -+ if (!bt) -+ goto err; -+ -+ bt->sequence = alloc_percpu(unsigned long); -+ if (!bt->sequence) -+ goto err; -+ -+ ret = -ENOENT; -+ dir = blk_create_tree(buts.name); -+ if (!dir) -+ goto err; -+ -+ bt->dir = dir; -+ bt->dev = bdev->bd_dev; -+ atomic_set(&bt->dropped, 0); -+ -+ ret = -EIO; -+ bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops); -+ if (!bt->dropped_file) -+ goto err; -+ -+ bt->rchan = relay_open("trace", dir, buts.buf_size, buts.buf_nr, &blk_relay_callbacks); -+ if (!bt->rchan) -+ goto err; -+ bt->rchan->private_data = bt; -+ -+ bt->act_mask = buts.act_mask; -+ if (!bt->act_mask) -+ bt->act_mask = (u16) -1; -+ -+ bt->start_lba = buts.start_lba; -+ bt->end_lba = buts.end_lba; -+ if (!bt->end_lba) -+ bt->end_lba = -1ULL; -+ -+ bt->pid = buts.pid; -+ bt->trace_state = Blktrace_setup; -+ -+ ret = -EBUSY; -+ old_bt = xchg(&q->blk_trace, bt); -+ if (old_bt) { -+ xchg(&q->blk_trace, old_bt); -+ goto err; -+ } -+ -+ return 0; -+err: -+ if (dir) -+ blk_remove_tree(dir); -+ if (bt) { -+ if (bt->dropped_file) -+ debugfs_remove(bt->dropped_file); -+ if (bt->sequence) -+ free_percpu(bt->sequence); -+ if (bt->rchan) -+ relay_close(bt->rchan); -+ kfree(bt); -+ } -+ return ret; -+} -+ -+static int blk_trace_startstop(request_queue_t *q, int start) -+{ -+ struct blk_trace *bt; -+ int ret; -+ -+ if ((bt = q->blk_trace) == NULL) -+ return -EINVAL; -+ -+ /* -+ * For starting a trace, we can transition from a setup or stopped -+ * trace. For stopping a trace, the state must be running -+ */ -+ ret = -EINVAL; -+ if (start) { -+ if (bt->trace_state == Blktrace_setup || -+ bt->trace_state == Blktrace_stopped) { -+ blktrace_seq++; -+ smp_mb(); -+ bt->trace_state = Blktrace_running; -+ ret = 0; -+ } -+ } else { -+ if (bt->trace_state == Blktrace_running) { -+ bt->trace_state = Blktrace_stopped; -+ ret = 0; -+ } -+ } -+ -+ return ret; -+} -+ -+/** -+ * blk_trace_ioctl: - handle the ioctls associated with tracing -+ * @bdev: the block device -+ * @cmd: the ioctl cmd -+ * @arg: the argument data, if any -+ * -+ **/ -+int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) -+{ -+ request_queue_t *q; -+ int ret, start = 0; -+ -+ q = bdev_get_queue(bdev); -+ if (!q) -+ return -ENXIO; -+ -+ down(&bdev->bd_sem); -+ -+ switch (cmd) { -+ case BLKTRACESETUP: -+ ret = blk_trace_setup(q, bdev, arg); -+ break; -+ case BLKTRACESTART: -+ start = 1; -+ case BLKTRACESTOP: -+ ret = blk_trace_startstop(q, start); -+ break; -+ case BLKTRACETEARDOWN: -+ ret = blk_trace_remove(q); -+ break; -+ default: -+ ret = -ENOTTY; -+ break; -+ } -+ -+ up(&bdev->bd_sem); -+ return ret; -+} -+ -+/** -+ * blk_trace_shutdown: - stop and cleanup trace structures -+ * @q: the request queue associated with the device -+ * -+ **/ -+void blk_trace_shutdown(request_queue_t *q) -+{ -+ blk_trace_startstop(q, 0); -+ blk_trace_remove(q); -+} -+ -+/* -+ * Average offset over two calls to sched_clock() with a gettimeofday() -+ * in the middle -+ */ -+static void blk_check_time(unsigned long long *t) -+{ -+ unsigned long long a, b; -+ struct timeval tv; -+ -+ a = sched_clock(); -+ do_gettimeofday(&tv); -+ b = sched_clock(); -+ -+ *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; -+ *t -= (a + b) / 2; -+} -+ -+static void blk_trace_check_cpu_time(void *data) -+{ -+ unsigned long long *t; -+ int cpu = get_cpu(); -+ -+ t = &per_cpu(blk_trace_cpu_offset, cpu); -+ -+ /* -+ * Just call it twice, hopefully the second call will be cache hot -+ * and a little more precise -+ */ -+ blk_check_time(t); -+ blk_check_time(t); -+ -+ put_cpu(); -+} -+ -+/* -+ * Call blk_trace_check_cpu_time() on each CPU to calibrate our inter-CPU -+ * timings -+ */ -+static void blk_trace_calibrate_offsets(void) -+{ -+ unsigned long flags; -+ -+ smp_call_function(blk_trace_check_cpu_time, NULL, 1, 1); -+ local_irq_save(flags); -+ blk_trace_check_cpu_time(NULL); -+ local_irq_restore(flags); -+} -+ -+static void blk_trace_set_ht_offsets(void) -+{ -+#if defined(CONFIG_SCHED_SMT) -+ int cpu, i; -+ -+ /* -+ * now make sure HT siblings have the same time offset -+ */ -+ preempt_disable(); -+ for_each_online_cpu(cpu) { -+ unsigned long long *cpu_off, *sibling_off; -+ -+ for_each_cpu_mask(i, cpu_sibling_map[cpu]) { -+ if (i == cpu) -+ continue; -+ -+ cpu_off = &per_cpu(blk_trace_cpu_offset, cpu); -+ sibling_off = &per_cpu(blk_trace_cpu_offset, i); -+ *sibling_off = *cpu_off; -+ } -+ } -+ preempt_enable(); -+#endif -+} -+ -+static __init int blk_trace_init(void) -+{ -+ mutex_init(&blk_tree_mutex); -+ blk_trace_calibrate_offsets(); -+ blk_trace_set_ht_offsets(); -+ -+ return 0; -+} -+ -+module_init(blk_trace_init); -+ -diff --git a/block/elevator.c b/block/elevator.c -index 24b702d..0c9fafe 100644 ---- a/block/elevator.c -+++ b/block/elevator.c -@@ -33,6 +33,7 @@ - #include - #include - #include -+#include - - #include - -@@ -315,6 +316,8 @@ void elv_insert(request_queue_t *q, stru - struct list_head *pos; - unsigned ordseq; - -+ blk_add_trace_rq(q, rq, BLK_TA_INSERT); -+ - rq->q = q; - - switch (where) { -@@ -481,6 +484,7 @@ struct request *elv_next_request(request - * not be passed by new incoming requests - */ - rq->flags |= REQ_STARTED; -+ blk_add_trace_rq(q, rq, BLK_TA_ISSUE); - } - - if (!q->boundary_rq || q->boundary_rq == rq) { -diff --git a/block/ioctl.c b/block/ioctl.c -index e110949..7acb56c 100644 ---- a/block/ioctl.c -+++ b/block/ioctl.c -@@ -5,6 +5,7 @@ - #include - #include - #include -+#include - #include - - static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) -@@ -189,6 +190,11 @@ static int blkdev_locked_ioctl(struct fi - return put_ulong(arg, bdev->bd_inode->i_size >> 9); - case BLKGETSIZE64: - return put_u64(arg, bdev->bd_inode->i_size); -+ case BLKTRACESTART: -+ case BLKTRACESTOP: -+ case BLKTRACESETUP: -+ case BLKTRACETEARDOWN: -+ return blk_trace_ioctl(bdev, cmd, (char __user *) arg); - } - return -ENOIOCTLCMD; - } -diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c -index 03d9c82..41387f5 100644 ---- a/block/ll_rw_blk.c -+++ b/block/ll_rw_blk.c -@@ -28,6 +28,7 @@ - #include - #include - #include -+#include - - /* - * for max sense size -@@ -1551,8 +1552,10 @@ void blk_plug_device(request_queue_t *q) - if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)) - return; - -- if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) -+ if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { - mod_timer(&q->unplug_timer, jiffies + q->unplug_delay); -+ blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG); -+ } - } - - EXPORT_SYMBOL(blk_plug_device); -@@ -1616,14 +1619,21 @@ static void blk_backing_dev_unplug(struc - /* - * devices don't necessarily have an ->unplug_fn defined - */ -- if (q->unplug_fn) -+ if (q->unplug_fn) { -+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL, -+ q->rq.count[READ] + q->rq.count[WRITE]); -+ - q->unplug_fn(q); -+ } - } - - static void blk_unplug_work(void *data) - { - request_queue_t *q = data; - -+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL, -+ q->rq.count[READ] + q->rq.count[WRITE]); -+ - q->unplug_fn(q); - } - -@@ -1631,6 +1641,9 @@ static void blk_unplug_timeout(unsigned - { - request_queue_t *q = (request_queue_t *)data; - -+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_TIMER, NULL, -+ q->rq.count[READ] + q->rq.count[WRITE]); -+ - kblockd_schedule_work(&q->unplug_work); - } - -@@ -1753,6 +1766,9 @@ void blk_cleanup_queue(request_queue_t * - if (q->queue_tags) - __blk_queue_free_tags(q); - -+ if (q->blk_trace) -+ blk_trace_shutdown(q); -+ - kmem_cache_free(requestq_cachep, q); - } - -@@ -2104,6 +2120,8 @@ rq_starved: - - rq_init(q, rq); - rq->rl = rl; -+ -+ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ); - out: - return rq; - } -@@ -2132,6 +2150,8 @@ static struct request *get_request_wait( - if (!rq) { - struct io_context *ioc; - -+ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ); -+ - __generic_unplug_device(q); - spin_unlock_irq(q->queue_lock); - io_schedule(); -@@ -2185,6 +2205,8 @@ EXPORT_SYMBOL(blk_get_request); - */ - void blk_requeue_request(request_queue_t *q, struct request *rq) - { -+ blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); -+ - if (blk_rq_tagged(rq)) - blk_queue_end_tag(q, rq); - -@@ -2819,6 +2841,8 @@ static int __make_request(request_queue_ - if (!q->back_merge_fn(q, req, bio)) - break; - -+ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); -+ - req->biotail->bi_next = bio; - req->biotail = bio; - req->nr_sectors = req->hard_nr_sectors += nr_sectors; -@@ -2834,6 +2858,8 @@ static int __make_request(request_queue_ - if (!q->front_merge_fn(q, req, bio)) - break; - -+ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); -+ - bio->bi_next = req->bio; - req->bio = bio; - -@@ -2951,6 +2977,7 @@ void generic_make_request(struct bio *bi - request_queue_t *q; - sector_t maxsector; - int ret, nr_sectors = bio_sectors(bio); -+ dev_t old_dev; - - might_sleep(); - /* Test device or partition size, when known. */ -@@ -2977,6 +3004,8 @@ void generic_make_request(struct bio *bi - * NOTE: we don't repeat the blk_size check for each new device. - * Stacking drivers are expected to know what they are doing. - */ -+ maxsector = -1; -+ old_dev = 0; - do { - char b[BDEVNAME_SIZE]; - -@@ -3009,6 +3038,15 @@ end_io: - */ - blk_partition_remap(bio); - -+ if (maxsector != -1) -+ blk_add_trace_remap(q, bio, old_dev, bio->bi_sector, -+ maxsector); -+ -+ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); -+ -+ maxsector = bio->bi_sector; -+ old_dev = bio->bi_bdev->bd_dev; -+ - ret = q->make_request_fn(q, bio); - } while (ret); - } -@@ -3128,6 +3166,8 @@ static int __end_that_request_first(stru - int total_bytes, bio_nbytes, error, next_idx = 0; - struct bio *bio; - -+ blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE); -+ - /* - * extend uptodate bool to allow < 0 value to be direct io error - */ -diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c -index 0d65394..234048e 100644 ---- a/drivers/block/cciss.c -+++ b/drivers/block/cciss.c -@@ -38,6 +38,7 @@ - #include - #include - #include -+#include - #include - #include - -@@ -2331,6 +2332,7 @@ static inline void complete_command( ctl - - cmd->rq->completion_data = cmd; - cmd->rq->errors = status; -+ blk_add_trace_rq(cmd->rq->q, cmd->rq, BLK_TA_COMPLETE); - blk_complete_request(cmd->rq); - } - -diff --git a/drivers/md/dm.c b/drivers/md/dm.c -index 745ca1f..f36613e 100644 ---- a/drivers/md/dm.c -+++ b/drivers/md/dm.c -@@ -17,6 +17,7 @@ - #include - #include - #include -+#include - - static const char *_name = DM_NAME; - -@@ -334,6 +335,8 @@ static void dec_pending(struct dm_io *io - /* nudge anyone waiting on suspend queue */ - wake_up(&io->md->wait); - -+ blk_add_trace_bio(io->md->queue, io->bio, BLK_TA_COMPLETE); -+ - bio_endio(io->bio, io->bio->bi_size, io->error); - free_io(io->md, io); - } -@@ -392,6 +395,7 @@ static void __map_bio(struct dm_target * - struct target_io *tio) - { - int r; -+ sector_t sector; - - /* - * Sanity checks. -@@ -407,10 +411,17 @@ static void __map_bio(struct dm_target * - * this io. - */ - atomic_inc(&tio->io->io_count); -+ sector = clone->bi_sector; - r = ti->type->map(ti, clone, &tio->info); -- if (r > 0) -+ if (r > 0) { - /* the bio has been remapped so dispatch it */ -+ -+ blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, -+ tio->io->bio->bi_bdev->bd_dev, sector, -+ clone->bi_sector); -+ - generic_make_request(clone); -+ } - - else if (r < 0) { - /* error the io and bail out */ -diff --git a/fs/Kconfig b/fs/Kconfig -index e9749b0..c8d0a20 100644 ---- a/fs/Kconfig -+++ b/fs/Kconfig -@@ -859,18 +859,6 @@ config RAMFS - To compile this as a module, choose M here: the module will be called - ramfs. - --config RELAYFS_FS -- tristate "Relayfs file system support" -- ---help--- -- Relayfs is a high-speed data relay filesystem designed to provide -- an efficient mechanism for tools and facilities to relay large -- amounts of data from kernel space to user space. -- -- To compile this code as a module, choose M here: the module will be -- called relayfs. -- -- If unsure, say N. -- - config CONFIGFS_FS - tristate "Userspace-driven configuration filesystem (EXPERIMENTAL)" - depends on EXPERIMENTAL -diff --git a/fs/Makefile b/fs/Makefile -index 1db7113..080b386 100644 ---- a/fs/Makefile -+++ b/fs/Makefile -@@ -91,7 +91,6 @@ obj-$(CONFIG_AUTOFS4_FS) += autofs4/ - obj-$(CONFIG_ADFS_FS) += adfs/ - obj-$(CONFIG_FUSE_FS) += fuse/ - obj-$(CONFIG_UDF_FS) += udf/ --obj-$(CONFIG_RELAYFS_FS) += relayfs/ - obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/ - obj-$(CONFIG_JFS_FS) += jfs/ - obj-$(CONFIG_XFS_FS) += xfs/ -diff --git a/fs/bio.c b/fs/bio.c -index 1f3bb50..0dd0d81 100644 ---- a/fs/bio.c -+++ b/fs/bio.c -@@ -25,6 +25,7 @@ - #include - #include - #include -+#include - #include /* for struct sg_iovec */ - - #define BIO_POOL_SIZE 256 -@@ -1095,6 +1096,9 @@ struct bio_pair *bio_split(struct bio *b - if (!bp) - return bp; - -+ blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi, -+ bi->bi_sector + first_sectors); -+ - BUG_ON(bi->bi_vcnt != 1); - BUG_ON(bi->bi_idx != 0); - atomic_set(&bp->cnt, 3); -diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c -index 537ac70..48318d9 100644 ---- a/fs/compat_ioctl.c -+++ b/fs/compat_ioctl.c -@@ -72,6 +72,7 @@ - #include - #include - #include -+#include - - #include /* siocdevprivate_ioctl */ - #include -diff --git a/fs/relayfs/Makefile b/fs/relayfs/Makefile -deleted file mode 100644 -index e76e182..0000000 ---- a/fs/relayfs/Makefile -+++ /dev/null -@@ -1,4 +0,0 @@ --obj-$(CONFIG_RELAYFS_FS) += relayfs.o -- --relayfs-y := relay.o inode.o buffers.o -- -diff --git a/fs/relayfs/buffers.c b/fs/relayfs/buffers.c -deleted file mode 100644 -index 1018781..0000000 ---- a/fs/relayfs/buffers.c -+++ /dev/null -@@ -1,190 +0,0 @@ --/* -- * RelayFS buffer management code. -- * -- * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp -- * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) -- * -- * This file is released under the GPL. -- */ -- --#include --#include --#include --#include --#include "relay.h" --#include "buffers.h" -- --/* -- * close() vm_op implementation for relayfs file mapping. -- */ --static void relay_file_mmap_close(struct vm_area_struct *vma) --{ -- struct rchan_buf *buf = vma->vm_private_data; -- buf->chan->cb->buf_unmapped(buf, vma->vm_file); --} -- --/* -- * nopage() vm_op implementation for relayfs file mapping. -- */ --static struct page *relay_buf_nopage(struct vm_area_struct *vma, -- unsigned long address, -- int *type) --{ -- struct page *page; -- struct rchan_buf *buf = vma->vm_private_data; -- unsigned long offset = address - vma->vm_start; -- -- if (address > vma->vm_end) -- return NOPAGE_SIGBUS; /* Disallow mremap */ -- if (!buf) -- return NOPAGE_OOM; -- -- page = vmalloc_to_page(buf->start + offset); -- if (!page) -- return NOPAGE_OOM; -- get_page(page); -- -- if (type) -- *type = VM_FAULT_MINOR; -- -- return page; --} -- --/* -- * vm_ops for relay file mappings. -- */ --static struct vm_operations_struct relay_file_mmap_ops = { -- .nopage = relay_buf_nopage, -- .close = relay_file_mmap_close, --}; -- --/** -- * relay_mmap_buf: - mmap channel buffer to process address space -- * @buf: relay channel buffer -- * @vma: vm_area_struct describing memory to be mapped -- * -- * Returns 0 if ok, negative on error -- * -- * Caller should already have grabbed mmap_sem. -- */ --int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) --{ -- unsigned long length = vma->vm_end - vma->vm_start; -- struct file *filp = vma->vm_file; -- -- if (!buf) -- return -EBADF; -- -- if (length != (unsigned long)buf->chan->alloc_size) -- return -EINVAL; -- -- vma->vm_ops = &relay_file_mmap_ops; -- vma->vm_private_data = buf; -- buf->chan->cb->buf_mapped(buf, filp); -- -- return 0; --} -- --/** -- * relay_alloc_buf - allocate a channel buffer -- * @buf: the buffer struct -- * @size: total size of the buffer -- * -- * Returns a pointer to the resulting buffer, NULL if unsuccessful -- */ --static void *relay_alloc_buf(struct rchan_buf *buf, unsigned long size) --{ -- void *mem; -- unsigned int i, j, n_pages; -- -- size = PAGE_ALIGN(size); -- n_pages = size >> PAGE_SHIFT; -- -- buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); -- if (!buf->page_array) -- return NULL; -- -- for (i = 0; i < n_pages; i++) { -- buf->page_array[i] = alloc_page(GFP_KERNEL); -- if (unlikely(!buf->page_array[i])) -- goto depopulate; -- } -- mem = vmap(buf->page_array, n_pages, VM_MAP, PAGE_KERNEL); -- if (!mem) -- goto depopulate; -- -- memset(mem, 0, size); -- buf->page_count = n_pages; -- return mem; -- --depopulate: -- for (j = 0; j < i; j++) -- __free_page(buf->page_array[j]); -- kfree(buf->page_array); -- return NULL; --} -- --/** -- * relay_create_buf - allocate and initialize a channel buffer -- * @alloc_size: size of the buffer to allocate -- * @n_subbufs: number of sub-buffers in the channel -- * -- * Returns channel buffer if successful, NULL otherwise -- */ --struct rchan_buf *relay_create_buf(struct rchan *chan) --{ -- struct rchan_buf *buf = kcalloc(1, sizeof(struct rchan_buf), GFP_KERNEL); -- if (!buf) -- return NULL; -- -- buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL); -- if (!buf->padding) -- goto free_buf; -- -- buf->start = relay_alloc_buf(buf, chan->alloc_size); -- if (!buf->start) -- goto free_buf; -- -- buf->chan = chan; -- kref_get(&buf->chan->kref); -- return buf; -- --free_buf: -- kfree(buf->padding); -- kfree(buf); -- return NULL; --} -- --/** -- * relay_destroy_buf - destroy an rchan_buf struct and associated buffer -- * @buf: the buffer struct -- */ --void relay_destroy_buf(struct rchan_buf *buf) --{ -- struct rchan *chan = buf->chan; -- unsigned int i; -- -- if (likely(buf->start)) { -- vunmap(buf->start); -- for (i = 0; i < buf->page_count; i++) -- __free_page(buf->page_array[i]); -- kfree(buf->page_array); -- } -- kfree(buf->padding); -- kfree(buf); -- kref_put(&chan->kref, relay_destroy_channel); --} -- --/** -- * relay_remove_buf - remove a channel buffer -- * -- * Removes the file from the relayfs fileystem, which also frees the -- * rchan_buf_struct and the channel buffer. Should only be called from -- * kref_put(). -- */ --void relay_remove_buf(struct kref *kref) --{ -- struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref); -- buf->chan->cb->remove_buf_file(buf->dentry); -- relay_destroy_buf(buf); --} -diff --git a/fs/relayfs/buffers.h b/fs/relayfs/buffers.h -deleted file mode 100644 -index 37a1249..0000000 ---- a/fs/relayfs/buffers.h -+++ /dev/null -@@ -1,12 +0,0 @@ --#ifndef _BUFFERS_H --#define _BUFFERS_H -- --/* This inspired by rtai/shmem */ --#define FIX_SIZE(x) (((x) - 1) & PAGE_MASK) + PAGE_SIZE -- --extern int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma); --extern struct rchan_buf *relay_create_buf(struct rchan *chan); --extern void relay_destroy_buf(struct rchan_buf *buf); --extern void relay_remove_buf(struct kref *kref); -- --#endif/* _BUFFERS_H */ -diff --git a/fs/relayfs/inode.c b/fs/relayfs/inode.c -deleted file mode 100644 -index 3835230..0000000 ---- a/fs/relayfs/inode.c -+++ /dev/null -@@ -1,581 +0,0 @@ --/* -- * VFS-related code for RelayFS, a high-speed data relay filesystem. -- * -- * Copyright (C) 2003-2005 - Tom Zanussi , IBM Corp -- * Copyright (C) 2003-2005 - Karim Yaghmour -- * -- * Based on ramfs, Copyright (C) 2002 - Linus Torvalds -- * -- * This file is released under the GPL. -- */ -- --#include --#include --#include --#include --#include --#include --#include --#include --#include --#include --#include "relay.h" --#include "buffers.h" -- --#define RELAYFS_MAGIC 0xF0B4A981 -- --static struct vfsmount * relayfs_mount; --static int relayfs_mount_count; -- --static struct backing_dev_info relayfs_backing_dev_info = { -- .ra_pages = 0, /* No readahead */ -- .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK, --}; -- --static struct inode *relayfs_get_inode(struct super_block *sb, -- int mode, -- struct file_operations *fops, -- void *data) --{ -- struct inode *inode; -- -- inode = new_inode(sb); -- if (!inode) -- return NULL; -- -- inode->i_mode = mode; -- inode->i_uid = 0; -- inode->i_gid = 0; -- inode->i_blksize = PAGE_CACHE_SIZE; -- inode->i_blocks = 0; -- inode->i_mapping->backing_dev_info = &relayfs_backing_dev_info; -- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; -- switch (mode & S_IFMT) { -- case S_IFREG: -- inode->i_fop = fops; -- if (data) -- inode->u.generic_ip = data; -- break; -- case S_IFDIR: -- inode->i_op = &simple_dir_inode_operations; -- inode->i_fop = &simple_dir_operations; -- -- /* directory inodes start off with i_nlink == 2 (for "." entry) */ -- inode->i_nlink++; -- break; -- default: -- break; -- } -- -- return inode; --} -- --/** -- * relayfs_create_entry - create a relayfs directory or file -- * @name: the name of the file to create -- * @parent: parent directory -- * @mode: mode -- * @fops: file operations to use for the file -- * @data: user-associated data for this file -- * -- * Returns the new dentry, NULL on failure -- * -- * Creates a file or directory with the specifed permissions. -- */ --static struct dentry *relayfs_create_entry(const char *name, -- struct dentry *parent, -- int mode, -- struct file_operations *fops, -- void *data) --{ -- struct dentry *d; -- struct inode *inode; -- int error = 0; -- -- BUG_ON(!name || !(S_ISREG(mode) || S_ISDIR(mode))); -- -- error = simple_pin_fs("relayfs", &relayfs_mount, &relayfs_mount_count); -- if (error) { -- printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", error); -- return NULL; -- } -- -- if (!parent && relayfs_mount && relayfs_mount->mnt_sb) -- parent = relayfs_mount->mnt_sb->s_root; -- -- if (!parent) { -- simple_release_fs(&relayfs_mount, &relayfs_mount_count); -- return NULL; -- } -- -- parent = dget(parent); -- mutex_lock(&parent->d_inode->i_mutex); -- d = lookup_one_len(name, parent, strlen(name)); -- if (IS_ERR(d)) { -- d = NULL; -- goto release_mount; -- } -- -- if (d->d_inode) { -- d = NULL; -- goto release_mount; -- } -- -- inode = relayfs_get_inode(parent->d_inode->i_sb, mode, fops, data); -- if (!inode) { -- d = NULL; -- goto release_mount; -- } -- -- d_instantiate(d, inode); -- dget(d); /* Extra count - pin the dentry in core */ -- -- if (S_ISDIR(mode)) -- parent->d_inode->i_nlink++; -- -- goto exit; -- --release_mount: -- simple_release_fs(&relayfs_mount, &relayfs_mount_count); -- --exit: -- mutex_unlock(&parent->d_inode->i_mutex); -- dput(parent); -- return d; --} -- --/** -- * relayfs_create_file - create a file in the relay filesystem -- * @name: the name of the file to create -- * @parent: parent directory -- * @mode: mode, if not specied the default perms are used -- * @fops: file operations to use for the file -- * @data: user-associated data for this file -- * -- * Returns file dentry if successful, NULL otherwise. -- * -- * The file will be created user r on behalf of current user. -- */ --struct dentry *relayfs_create_file(const char *name, -- struct dentry *parent, -- int mode, -- struct file_operations *fops, -- void *data) --{ -- BUG_ON(!fops); -- -- if (!mode) -- mode = S_IRUSR; -- mode = (mode & S_IALLUGO) | S_IFREG; -- -- return relayfs_create_entry(name, parent, mode, fops, data); --} -- --/** -- * relayfs_create_dir - create a directory in the relay filesystem -- * @name: the name of the directory to create -- * @parent: parent directory, NULL if parent should be fs root -- * -- * Returns directory dentry if successful, NULL otherwise. -- * -- * The directory will be created world rwx on behalf of current user. -- */ --struct dentry *relayfs_create_dir(const char *name, struct dentry *parent) --{ -- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; -- return relayfs_create_entry(name, parent, mode, NULL, NULL); --} -- --/** -- * relayfs_remove - remove a file or directory in the relay filesystem -- * @dentry: file or directory dentry -- * -- * Returns 0 if successful, negative otherwise. -- */ --int relayfs_remove(struct dentry *dentry) --{ -- struct dentry *parent; -- int error = 0; -- -- if (!dentry) -- return -EINVAL; -- parent = dentry->d_parent; -- if (!parent) -- return -EINVAL; -- -- parent = dget(parent); -- mutex_lock(&parent->d_inode->i_mutex); -- if (dentry->d_inode) { -- if (S_ISDIR(dentry->d_inode->i_mode)) -- error = simple_rmdir(parent->d_inode, dentry); -- else -- error = simple_unlink(parent->d_inode, dentry); -- if (!error) -- d_delete(dentry); -- } -- if (!error) -- dput(dentry); -- mutex_unlock(&parent->d_inode->i_mutex); -- dput(parent); -- -- if (!error) -- simple_release_fs(&relayfs_mount, &relayfs_mount_count); -- -- return error; --} -- --/** -- * relayfs_remove_file - remove a file from relay filesystem -- * @dentry: directory dentry -- * -- * Returns 0 if successful, negative otherwise. -- */ --int relayfs_remove_file(struct dentry *dentry) --{ -- return relayfs_remove(dentry); --} -- --/** -- * relayfs_remove_dir - remove a directory in the relay filesystem -- * @dentry: directory dentry -- * -- * Returns 0 if successful, negative otherwise. -- */ --int relayfs_remove_dir(struct dentry *dentry) --{ -- return relayfs_remove(dentry); --} -- --/** -- * relay_file_open - open file op for relay files -- * @inode: the inode -- * @filp: the file -- * -- * Increments the channel buffer refcount. -- */ --static int relay_file_open(struct inode *inode, struct file *filp) --{ -- struct rchan_buf *buf = inode->u.generic_ip; -- kref_get(&buf->kref); -- filp->private_data = buf; -- -- return 0; --} -- --/** -- * relay_file_mmap - mmap file op for relay files -- * @filp: the file -- * @vma: the vma describing what to map -- * -- * Calls upon relay_mmap_buf to map the file into user space. -- */ --static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) --{ -- struct rchan_buf *buf = filp->private_data; -- return relay_mmap_buf(buf, vma); --} -- --/** -- * relay_file_poll - poll file op for relay files -- * @filp: the file -- * @wait: poll table -- * -- * Poll implemention. -- */ --static unsigned int relay_file_poll(struct file *filp, poll_table *wait) --{ -- unsigned int mask = 0; -- struct rchan_buf *buf = filp->private_data; -- -- if (buf->finalized) -- return POLLERR; -- -- if (filp->f_mode & FMODE_READ) { -- poll_wait(filp, &buf->read_wait, wait); -- if (!relay_buf_empty(buf)) -- mask |= POLLIN | POLLRDNORM; -- } -- -- return mask; --} -- --/** -- * relay_file_release - release file op for relay files -- * @inode: the inode -- * @filp: the file -- * -- * Decrements the channel refcount, as the filesystem is -- * no longer using it. -- */ --static int relay_file_release(struct inode *inode, struct file *filp) --{ -- struct rchan_buf *buf = filp->private_data; -- kref_put(&buf->kref, relay_remove_buf); -- -- return 0; --} -- --/** -- * relay_file_read_consume - update the consumed count for the buffer -- */ --static void relay_file_read_consume(struct rchan_buf *buf, -- size_t read_pos, -- size_t bytes_consumed) --{ -- size_t subbuf_size = buf->chan->subbuf_size; -- size_t n_subbufs = buf->chan->n_subbufs; -- size_t read_subbuf; -- -- if (buf->bytes_consumed + bytes_consumed > subbuf_size) { -- relay_subbufs_consumed(buf->chan, buf->cpu, 1); -- buf->bytes_consumed = 0; -- } -- -- buf->bytes_consumed += bytes_consumed; -- read_subbuf = read_pos / buf->chan->subbuf_size; -- if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) { -- if ((read_subbuf == buf->subbufs_produced % n_subbufs) && -- (buf->offset == subbuf_size)) -- return; -- relay_subbufs_consumed(buf->chan, buf->cpu, 1); -- buf->bytes_consumed = 0; -- } --} -- --/** -- * relay_file_read_avail - boolean, are there unconsumed bytes available? -- */ --static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos) --{ -- size_t bytes_produced, bytes_consumed, write_offset; -- size_t subbuf_size = buf->chan->subbuf_size; -- size_t n_subbufs = buf->chan->n_subbufs; -- size_t produced = buf->subbufs_produced % n_subbufs; -- size_t consumed = buf->subbufs_consumed % n_subbufs; -- -- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; -- -- if (consumed > produced) { -- if ((produced > n_subbufs) && -- (produced + n_subbufs - consumed <= n_subbufs)) -- produced += n_subbufs; -- } else if (consumed == produced) { -- if (buf->offset > subbuf_size) { -- produced += n_subbufs; -- if (buf->subbufs_produced == buf->subbufs_consumed) -- consumed += n_subbufs; -- } -- } -- -- if (buf->offset > subbuf_size) -- bytes_produced = (produced - 1) * subbuf_size + write_offset; -- else -- bytes_produced = produced * subbuf_size + write_offset; -- bytes_consumed = consumed * subbuf_size + buf->bytes_consumed; -- -- if (bytes_produced == bytes_consumed) -- return 0; -- -- relay_file_read_consume(buf, read_pos, 0); -- -- return 1; --} -- --/** -- * relay_file_read_subbuf_avail - return bytes available in sub-buffer -- */ --static size_t relay_file_read_subbuf_avail(size_t read_pos, -- struct rchan_buf *buf) --{ -- size_t padding, avail = 0; -- size_t read_subbuf, read_offset, write_subbuf, write_offset; -- size_t subbuf_size = buf->chan->subbuf_size; -- -- write_subbuf = (buf->data - buf->start) / subbuf_size; -- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; -- read_subbuf = read_pos / subbuf_size; -- read_offset = read_pos % subbuf_size; -- padding = buf->padding[read_subbuf]; -- -- if (read_subbuf == write_subbuf) { -- if (read_offset + padding < write_offset) -- avail = write_offset - (read_offset + padding); -- } else -- avail = (subbuf_size - padding) - read_offset; -- -- return avail; --} -- --/** -- * relay_file_read_start_pos - find the first available byte to read -- * -- * If the read_pos is in the middle of padding, return the -- * position of the first actually available byte, otherwise -- * return the original value. -- */ --static size_t relay_file_read_start_pos(size_t read_pos, -- struct rchan_buf *buf) --{ -- size_t read_subbuf, padding, padding_start, padding_end; -- size_t subbuf_size = buf->chan->subbuf_size; -- size_t n_subbufs = buf->chan->n_subbufs; -- -- read_subbuf = read_pos / subbuf_size; -- padding = buf->padding[read_subbuf]; -- padding_start = (read_subbuf + 1) * subbuf_size - padding; -- padding_end = (read_subbuf + 1) * subbuf_size; -- if (read_pos >= padding_start && read_pos < padding_end) { -- read_subbuf = (read_subbuf + 1) % n_subbufs; -- read_pos = read_subbuf * subbuf_size; -- } -- -- return read_pos; --} -- --/** -- * relay_file_read_end_pos - return the new read position -- */ --static size_t relay_file_read_end_pos(struct rchan_buf *buf, -- size_t read_pos, -- size_t count) --{ -- size_t read_subbuf, padding, end_pos; -- size_t subbuf_size = buf->chan->subbuf_size; -- size_t n_subbufs = buf->chan->n_subbufs; -- -- read_subbuf = read_pos / subbuf_size; -- padding = buf->padding[read_subbuf]; -- if (read_pos % subbuf_size + count + padding == subbuf_size) -- end_pos = (read_subbuf + 1) * subbuf_size; -- else -- end_pos = read_pos + count; -- if (end_pos >= subbuf_size * n_subbufs) -- end_pos = 0; -- -- return end_pos; --} -- --/** -- * relay_file_read - read file op for relay files -- * @filp: the file -- * @buffer: the userspace buffer -- * @count: number of bytes to read -- * @ppos: position to read from -- * -- * Reads count bytes or the number of bytes available in the -- * current sub-buffer being read, whichever is smaller. -- */ --static ssize_t relay_file_read(struct file *filp, -- char __user *buffer, -- size_t count, -- loff_t *ppos) --{ -- struct rchan_buf *buf = filp->private_data; -- struct inode *inode = filp->f_dentry->d_inode; -- size_t read_start, avail; -- ssize_t ret = 0; -- void *from; -- -- mutex_lock(&inode->i_mutex); -- if(!relay_file_read_avail(buf, *ppos)) -- goto out; -- -- read_start = relay_file_read_start_pos(*ppos, buf); -- avail = relay_file_read_subbuf_avail(read_start, buf); -- if (!avail) -- goto out; -- -- from = buf->start + read_start; -- ret = count = min(count, avail); -- if (copy_to_user(buffer, from, count)) { -- ret = -EFAULT; -- goto out; -- } -- relay_file_read_consume(buf, read_start, count); -- *ppos = relay_file_read_end_pos(buf, read_start, count); --out: -- mutex_unlock(&inode->i_mutex); -- return ret; --} -- --struct file_operations relay_file_operations = { -- .open = relay_file_open, -- .poll = relay_file_poll, -- .mmap = relay_file_mmap, -- .read = relay_file_read, -- .llseek = no_llseek, -- .release = relay_file_release, --}; -- --static struct super_operations relayfs_ops = { -- .statfs = simple_statfs, -- .drop_inode = generic_delete_inode, --}; -- --static int relayfs_fill_super(struct super_block * sb, void * data, int silent) --{ -- struct inode *inode; -- struct dentry *root; -- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; -- -- sb->s_blocksize = PAGE_CACHE_SIZE; -- sb->s_blocksize_bits = PAGE_CACHE_SHIFT; -- sb->s_magic = RELAYFS_MAGIC; -- sb->s_op = &relayfs_ops; -- inode = relayfs_get_inode(sb, mode, NULL, NULL); -- -- if (!inode) -- return -ENOMEM; -- -- root = d_alloc_root(inode); -- if (!root) { -- iput(inode); -- return -ENOMEM; -- } -- sb->s_root = root; -- -- return 0; --} -- --static struct super_block * relayfs_get_sb(struct file_system_type *fs_type, -- int flags, const char *dev_name, -- void *data) --{ -- return get_sb_single(fs_type, flags, data, relayfs_fill_super); --} -- --static struct file_system_type relayfs_fs_type = { -- .owner = THIS_MODULE, -- .name = "relayfs", -- .get_sb = relayfs_get_sb, -- .kill_sb = kill_litter_super, --}; -- --static int __init init_relayfs_fs(void) --{ -- return register_filesystem(&relayfs_fs_type); --} -- --static void __exit exit_relayfs_fs(void) --{ -- -- -- -- -- -- unregister_filesystem(&relayfs_fs_type); --} -- --module_init(init_relayfs_fs) --module_exit(exit_relayfs_fs) -- --EXPORT_SYMBOL_GPL(relay_file_operations); --EXPORT_SYMBOL_GPL(relayfs_create_dir); --EXPORT_SYMBOL_GPL(relayfs_remove_dir); --EXPORT_SYMBOL_GPL(relayfs_create_file); --EXPORT_SYMBOL_GPL(relayfs_remove_file); -- --MODULE_AUTHOR("Tom Zanussi and Karim Yaghmour "); --MODULE_DESCRIPTION("Relay Filesystem"); --MODULE_LICENSE("GPL"); -- -diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c -deleted file mode 100644 -index abf3cea..0000000 ---- a/fs/relayfs/relay.c -+++ /dev/null -@@ -1,482 +0,0 @@ --/* -- * Public API and common code for RelayFS. -- * -- * See Documentation/filesystems/relayfs.txt for an overview of relayfs. -- * -- * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp -- * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) -- * -- * This file is released under the GPL. -- */ -- --#include --#include --#include --#include --#include --#include --#include "relay.h" --#include "buffers.h" -- --/** -- * relay_buf_empty - boolean, is the channel buffer empty? -- * @buf: channel buffer -- * -- * Returns 1 if the buffer is empty, 0 otherwise. -- */ --int relay_buf_empty(struct rchan_buf *buf) --{ -- return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1; --} -- --/** -- * relay_buf_full - boolean, is the channel buffer full? -- * @buf: channel buffer -- * -- * Returns 1 if the buffer is full, 0 otherwise. -- */ --int relay_buf_full(struct rchan_buf *buf) --{ -- size_t ready = buf->subbufs_produced - buf->subbufs_consumed; -- return (ready >= buf->chan->n_subbufs) ? 1 : 0; --} -- --/* -- * High-level relayfs kernel API and associated functions. -- */ -- --/* -- * rchan_callback implementations defining default channel behavior. Used -- * in place of corresponding NULL values in client callback struct. -- */ -- --/* -- * subbuf_start() default callback. Does nothing. -- */ --static int subbuf_start_default_callback (struct rchan_buf *buf, -- void *subbuf, -- void *prev_subbuf, -- size_t prev_padding) --{ -- if (relay_buf_full(buf)) -- return 0; -- -- return 1; --} -- --/* -- * buf_mapped() default callback. Does nothing. -- */ --static void buf_mapped_default_callback(struct rchan_buf *buf, -- struct file *filp) --{ --} -- --/* -- * buf_unmapped() default callback. Does nothing. -- */ --static void buf_unmapped_default_callback(struct rchan_buf *buf, -- struct file *filp) --{ --} -- --/* -- * create_buf_file_create() default callback. Creates file to represent buf. -- */ --static struct dentry *create_buf_file_default_callback(const char *filename, -- struct dentry *parent, -- int mode, -- struct rchan_buf *buf, -- int *is_global) --{ -- return relayfs_create_file(filename, parent, mode, -- &relay_file_operations, buf); --} -- --/* -- * remove_buf_file() default callback. Removes file representing relay buffer. -- */ --static int remove_buf_file_default_callback(struct dentry *dentry) --{ -- return relayfs_remove(dentry); --} -- --/* relay channel default callbacks */ --static struct rchan_callbacks default_channel_callbacks = { -- .subbuf_start = subbuf_start_default_callback, -- .buf_mapped = buf_mapped_default_callback, -- .buf_unmapped = buf_unmapped_default_callback, -- .create_buf_file = create_buf_file_default_callback, -- .remove_buf_file = remove_buf_file_default_callback, --}; -- --/** -- * wakeup_readers - wake up readers waiting on a channel -- * @private: the channel buffer -- * -- * This is the work function used to defer reader waking. The -- * reason waking is deferred is that calling directly from write -- * causes problems if you're writing from say the scheduler. -- */ --static void wakeup_readers(void *private) --{ -- struct rchan_buf *buf = private; -- wake_up_interruptible(&buf->read_wait); --} -- --/** -- * __relay_reset - reset a channel buffer -- * @buf: the channel buffer -- * @init: 1 if this is a first-time initialization -- * -- * See relay_reset for description of effect. -- */ --static inline void __relay_reset(struct rchan_buf *buf, unsigned int init) --{ -- size_t i; -- -- if (init) { -- init_waitqueue_head(&buf->read_wait); -- kref_init(&buf->kref); -- INIT_WORK(&buf->wake_readers, NULL, NULL); -- } else { -- cancel_delayed_work(&buf->wake_readers); -- flush_scheduled_work(); -- } -- -- buf->subbufs_produced = 0; -- buf->subbufs_consumed = 0; -- buf->bytes_consumed = 0; -- buf->finalized = 0; -- buf->data = buf->start; -- buf->offset = 0; -- -- for (i = 0; i < buf->chan->n_subbufs; i++) -- buf->padding[i] = 0; -- -- buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0); --} -- --/** -- * relay_reset - reset the channel -- * @chan: the channel -- * -- * This has the effect of erasing all data from all channel buffers -- * and restarting the channel in its initial state. The buffers -- * are not freed, so any mappings are still in effect. -- * -- * NOTE: Care should be taken that the channel isn't actually -- * being used by anything when this call is made. -- */ --void relay_reset(struct rchan *chan) --{ -- unsigned int i; -- struct rchan_buf *prev = NULL; -- -- if (!chan) -- return; -- -- for (i = 0; i < NR_CPUS; i++) { -- if (!chan->buf[i] || chan->buf[i] == prev) -- break; -- __relay_reset(chan->buf[i], 0); -- prev = chan->buf[i]; -- } --} -- --/** -- * relay_open_buf - create a new channel buffer in relayfs -- * -- * Internal - used by relay_open(). -- */ --static struct rchan_buf *relay_open_buf(struct rchan *chan, -- const char *filename, -- struct dentry *parent, -- int *is_global) --{ -- struct rchan_buf *buf; -- struct dentry *dentry; -- -- if (*is_global) -- return chan->buf[0]; -- -- buf = relay_create_buf(chan); -- if (!buf) -- return NULL; -- -- /* Create file in fs */ -- dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR, -- buf, is_global); -- if (!dentry) { -- relay_destroy_buf(buf); -- return NULL; -- } -- -- buf->dentry = dentry; -- __relay_reset(buf, 1); -- -- return buf; --} -- --/** -- * relay_close_buf - close a channel buffer -- * @buf: channel buffer -- * -- * Marks the buffer finalized and restores the default callbacks. -- * The channel buffer and channel buffer data structure are then freed -- * automatically when the last reference is given up. -- */ --static inline void relay_close_buf(struct rchan_buf *buf) --{ -- buf->finalized = 1; -- buf->chan->cb = &default_channel_callbacks; -- cancel_delayed_work(&buf->wake_readers); -- flush_scheduled_work(); -- kref_put(&buf->kref, relay_remove_buf); --} -- --static inline void setup_callbacks(struct rchan *chan, -- struct rchan_callbacks *cb) --{ -- if (!cb) { -- chan->cb = &default_channel_callbacks; -- return; -- } -- -- if (!cb->subbuf_start) -- cb->subbuf_start = subbuf_start_default_callback; -- if (!cb->buf_mapped) -- cb->buf_mapped = buf_mapped_default_callback; -- if (!cb->buf_unmapped) -- cb->buf_unmapped = buf_unmapped_default_callback; -- if (!cb->create_buf_file) -- cb->create_buf_file = create_buf_file_default_callback; -- if (!cb->remove_buf_file) -- cb->remove_buf_file = remove_buf_file_default_callback; -- chan->cb = cb; --} -- --/** -- * relay_open - create a new relayfs channel -- * @base_filename: base name of files to create -- * @parent: dentry of parent directory, NULL for root directory -- * @subbuf_size: size of sub-buffers -- * @n_subbufs: number of sub-buffers -- * @cb: client callback functions -- * -- * Returns channel pointer if successful, NULL otherwise. -- * -- * Creates a channel buffer for each cpu using the sizes and -- * attributes specified. The created channel buffer files -- * will be named base_filename0...base_filenameN-1. File -- * permissions will be S_IRUSR. -- */ --struct rchan *relay_open(const char *base_filename, -- struct dentry *parent, -- size_t subbuf_size, -- size_t n_subbufs, -- struct rchan_callbacks *cb) --{ -- unsigned int i; -- struct rchan *chan; -- char *tmpname; -- int is_global = 0; -- -- if (!base_filename) -- return NULL; -- -- if (!(subbuf_size && n_subbufs)) -- return NULL; -- -- chan = kcalloc(1, sizeof(struct rchan), GFP_KERNEL); -- if (!chan) -- return NULL; -- -- chan->version = RELAYFS_CHANNEL_VERSION; -- chan->n_subbufs = n_subbufs; -- chan->subbuf_size = subbuf_size; -- chan->alloc_size = FIX_SIZE(subbuf_size * n_subbufs); -- setup_callbacks(chan, cb); -- kref_init(&chan->kref); -- -- tmpname = kmalloc(NAME_MAX + 1, GFP_KERNEL); -- if (!tmpname) -- goto free_chan; -- -- for_each_online_cpu(i) { -- sprintf(tmpname, "%s%d", base_filename, i); -- chan->buf[i] = relay_open_buf(chan, tmpname, parent, -- &is_global); -- chan->buf[i]->cpu = i; -- if (!chan->buf[i]) -- goto free_bufs; -- } -- -- kfree(tmpname); -- return chan; -- --free_bufs: -- for (i = 0; i < NR_CPUS; i++) { -- if (!chan->buf[i]) -- break; -- relay_close_buf(chan->buf[i]); -- if (is_global) -- break; -- } -- kfree(tmpname); -- --free_chan: -- kref_put(&chan->kref, relay_destroy_channel); -- return NULL; --} -- --/** -- * relay_switch_subbuf - switch to a new sub-buffer -- * @buf: channel buffer -- * @length: size of current event -- * -- * Returns either the length passed in or 0 if full. -- -- * Performs sub-buffer-switch tasks such as invoking callbacks, -- * updating padding counts, waking up readers, etc. -- */ --size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length) --{ -- void *old, *new; -- size_t old_subbuf, new_subbuf; -- -- if (unlikely(length > buf->chan->subbuf_size)) -- goto toobig; -- -- if (buf->offset != buf->chan->subbuf_size + 1) { -- buf->prev_padding = buf->chan->subbuf_size - buf->offset; -- old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; -- buf->padding[old_subbuf] = buf->prev_padding; -- buf->subbufs_produced++; -- if (waitqueue_active(&buf->read_wait)) { -- PREPARE_WORK(&buf->wake_readers, wakeup_readers, buf); -- schedule_delayed_work(&buf->wake_readers, 1); -- } -- } -- -- old = buf->data; -- new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; -- new = buf->start + new_subbuf * buf->chan->subbuf_size; -- buf->offset = 0; -- if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { -- buf->offset = buf->chan->subbuf_size + 1; -- return 0; -- } -- buf->data = new; -- buf->padding[new_subbuf] = 0; -- -- if (unlikely(length + buf->offset > buf->chan->subbuf_size)) -- goto toobig; -- -- return length; -- --toobig: -- buf->chan->last_toobig = length; -- return 0; --} -- --/** -- * relay_subbufs_consumed - update the buffer's sub-buffers-consumed count -- * @chan: the channel -- * @cpu: the cpu associated with the channel buffer to update -- * @subbufs_consumed: number of sub-buffers to add to current buf's count -- * -- * Adds to the channel buffer's consumed sub-buffer count. -- * subbufs_consumed should be the number of sub-buffers newly consumed, -- * not the total consumed. -- * -- * NOTE: kernel clients don't need to call this function if the channel -- * mode is 'overwrite'. -- */ --void relay_subbufs_consumed(struct rchan *chan, -- unsigned int cpu, -- size_t subbufs_consumed) --{ -- struct rchan_buf *buf; -- -- if (!chan) -- return; -- -- if (cpu >= NR_CPUS || !chan->buf[cpu]) -- return; -- -- buf = chan->buf[cpu]; -- buf->subbufs_consumed += subbufs_consumed; -- if (buf->subbufs_consumed > buf->subbufs_produced) -- buf->subbufs_consumed = buf->subbufs_produced; --} -- --/** -- * relay_destroy_channel - free the channel struct -- * -- * Should only be called from kref_put(). -- */ --void relay_destroy_channel(struct kref *kref) --{ -- struct rchan *chan = container_of(kref, struct rchan, kref); -- kfree(chan); --} -- --/** -- * relay_close - close the channel -- * @chan: the channel -- * -- * Closes all channel buffers and frees the channel. -- */ --void relay_close(struct rchan *chan) --{ -- unsigned int i; -- struct rchan_buf *prev = NULL; -- -- if (!chan) -- return; -- -- for (i = 0; i < NR_CPUS; i++) { -- if (!chan->buf[i] || chan->buf[i] == prev) -- break; -- relay_close_buf(chan->buf[i]); -- prev = chan->buf[i]; -- } -- -- if (chan->last_toobig) -- printk(KERN_WARNING "relayfs: one or more items not logged " -- "[item size (%Zd) > sub-buffer size (%Zd)]\n", -- chan->last_toobig, chan->subbuf_size); -- -- kref_put(&chan->kref, relay_destroy_channel); --} -- --/** -- * relay_flush - close the channel -- * @chan: the channel -- * -- * Flushes all channel buffers i.e. forces buffer switch. -- */ --void relay_flush(struct rchan *chan) --{ -- unsigned int i; -- struct rchan_buf *prev = NULL; -- -- if (!chan) -- return; -- -- for (i = 0; i < NR_CPUS; i++) { -- if (!chan->buf[i] || chan->buf[i] == prev) -- break; -- relay_switch_subbuf(chan->buf[i], 0); -- prev = chan->buf[i]; -- } --} -- --EXPORT_SYMBOL_GPL(relay_open); --EXPORT_SYMBOL_GPL(relay_close); --EXPORT_SYMBOL_GPL(relay_flush); --EXPORT_SYMBOL_GPL(relay_reset); --EXPORT_SYMBOL_GPL(relay_subbufs_consumed); --EXPORT_SYMBOL_GPL(relay_switch_subbuf); --EXPORT_SYMBOL_GPL(relay_buf_full); -diff --git a/fs/relayfs/relay.h b/fs/relayfs/relay.h -deleted file mode 100644 -index 0993d3e..0000000 ---- a/fs/relayfs/relay.h -+++ /dev/null -@@ -1,8 +0,0 @@ --#ifndef _RELAY_H --#define _RELAY_H -- --extern int relayfs_remove(struct dentry *dentry); --extern int relay_buf_empty(struct rchan_buf *buf); --extern void relay_destroy_channel(struct kref *kref); -- --#endif /* _RELAY_H */ -diff --git a/fs/sysfs/Makefile b/fs/sysfs/Makefile -index 7a1ceb9..7bd4d8f 100644 ---- a/fs/sysfs/Makefile -+++ b/fs/sysfs/Makefile -@@ -4,3 +4,4 @@ - - obj-y := inode.o file.o dir.o symlink.o mount.o bin.o \ - group.o -+obj-$(CONFIG_RELAY) += relay.o -diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c -index 49bd219..52a759b 100644 ---- a/fs/sysfs/dir.c -+++ b/fs/sysfs/dir.c -@@ -87,6 +87,20 @@ static int init_file(struct inode * inod - return 0; - } - -+#ifdef CONFIG_RELAY -+static int init_relay_file(struct inode * inode) -+{ -+ extern struct file_operations relay_file_operations; -+ inode->i_fop = &relay_file_operations; -+ return 0; -+} -+#else -+static int init_relay_file(struct inode * inode) -+{ -+ return -EINVAL; -+} -+#endif -+ - static int init_symlink(struct inode * inode) - { - inode->i_op = &sysfs_symlink_inode_operations; -@@ -165,6 +179,7 @@ int sysfs_create_dir(struct kobject * ko - static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry) - { - struct attribute * attr = NULL; -+ struct relay_attribute * rel_attr = NULL; - struct bin_attribute * bin_attr = NULL; - int (* init) (struct inode *) = NULL; - int error = 0; -@@ -172,6 +187,10 @@ static int sysfs_attach_attr(struct sysf - if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) { - bin_attr = sd->s_element; - attr = &bin_attr->attr; -+ } else if (sd->s_type & SYSFS_KOBJ_RELAY_ATTR) { -+ rel_attr = sd->s_element; -+ attr = &rel_attr->attr; -+ init = init_relay_file; - } else { - attr = sd->s_element; - init = init_file; -@@ -189,6 +208,13 @@ static int sysfs_attach_attr(struct sysf - dentry->d_inode->i_size = bin_attr->size; - dentry->d_inode->i_fop = &bin_fops; - } -+ -+ if (rel_attr) { -+ unsigned int size = rel_attr->subbuf_size * rel_attr->n_subbufs; -+ dentry->d_inode->i_size = ((size - 1) & PAGE_MASK) + PAGE_SIZE; -+ dentry->d_inode->u.generic_ip = rel_attr->rchan_buf; -+ } -+ - dentry->d_op = &sysfs_dentry_ops; - d_rehash(dentry); - -diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c -index 689f7bc..d41cb6d 100644 ---- a/fs/sysfs/inode.c -+++ b/fs/sysfs/inode.c -@@ -174,6 +174,7 @@ const unsigned char * sysfs_get_name(str - { - struct attribute * attr; - struct bin_attribute * bin_attr; -+ struct relay_attribute * rel_attr; - struct sysfs_symlink * sl; - - if (!sd || !sd->s_element) -@@ -192,6 +193,10 @@ const unsigned char * sysfs_get_name(str - bin_attr = sd->s_element; - return bin_attr->attr.name; - -+ case SYSFS_KOBJ_RELAY_ATTR: -+ rel_attr = sd->s_element; -+ return rel_attr->attr.name; -+ - case SYSFS_KOBJ_LINK: - sl = sd->s_element; - return sl->link_name; -diff --git a/fs/sysfs/relay.c b/fs/sysfs/relay.c -new file mode 100644 -index 0000000..f40de18 ---- /dev/null -+++ b/fs/sysfs/relay.c -@@ -0,0 +1,70 @@ -+/* -+ * relay.c - relay channel buffer support for sysfs -+ * -+ * Copyright (C) 2006 Paul Mundt -+ * -+ * This file is subject to the terms and conditions of the GNU General Public -+ * License. See the file "COPYING" in the main directory of this archive -+ * for more details. -+ */ -+#include -+#include -+#include -+#include "sysfs.h" -+ -+static struct dentry * -+sysfs_create_buf_file(const char *filename, struct dentry *dentry, int mode, -+ struct rchan_buf *buf, int *is_global) -+{ -+ struct relay_attribute *attr = (struct relay_attribute *)dentry; -+ struct dentry *parent = attr->kobj->dentry; -+ int ret; -+ -+ attr->attr.mode = mode; -+ attr->rchan_buf = buf; -+ -+ ret = sysfs_add_file(parent, &attr->attr, SYSFS_KOBJ_RELAY_ATTR); -+ if (unlikely(ret != 0)) -+ return NULL; -+ -+ dentry = lookup_one_len(filename, parent, strlen(filename)); -+ if (IS_ERR(dentry)) -+ sysfs_hash_and_remove(parent, filename); -+ -+ return dentry; -+} -+ -+static int sysfs_remove_buf_file(struct dentry *dentry) -+{ -+ sysfs_hash_and_remove(dentry, dentry->d_name.name); -+ return 0; -+} -+ -+struct rchan_callbacks sysfs_rchan_callbacks = { -+ .create_buf_file = sysfs_create_buf_file, -+ .remove_buf_file = sysfs_remove_buf_file, -+}; -+ -+int sysfs_create_relay_file(struct kobject *kobj, struct relay_attribute *attr) -+{ -+ BUG_ON(!kobj || !kobj->dentry || !attr); -+ -+ attr->kobj = kobj; -+ -+ attr->rchan = relay_open(attr->attr.name, (void *)attr, -+ attr->subbuf_size, attr->n_subbufs, -+ &sysfs_rchan_callbacks); -+ if (IS_ERR(attr->rchan)) -+ return PTR_ERR(attr->rchan); -+ -+ return 0; -+} -+EXPORT_SYMBOL_GPL(sysfs_create_relay_file); -+ -+void sysfs_remove_relay_file(struct kobject *kobj, struct relay_attribute *attr) -+{ -+ BUG_ON(!attr); -+ -+ relay_close(attr->rchan); -+} -+EXPORT_SYMBOL_GPL(sysfs_remove_relay_file); -diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h -index 860e7a4..266ce9d 100644 ---- a/include/linux/blkdev.h -+++ b/include/linux/blkdev.h -@@ -22,6 +22,7 @@ typedef struct request_queue request_que - struct elevator_queue; - typedef struct elevator_queue elevator_t; - struct request_pm_state; -+struct blk_trace; - - #define BLKDEV_MIN_RQ 4 - #define BLKDEV_MAX_RQ 128 /* Default maximum */ -@@ -416,6 +417,8 @@ struct request_queue - unsigned int sg_reserved_size; - int node; - -+ struct blk_trace *blk_trace; -+ - /* - * reserved for flush operations - */ -diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h -new file mode 100644 -index 0000000..b34d3e7 ---- /dev/null -+++ b/include/linux/blktrace_api.h -@@ -0,0 +1,277 @@ -+#ifndef BLKTRACE_H -+#define BLKTRACE_H -+ -+#include -+#include -+#include -+ -+/* -+ * Trace categories -+ */ -+enum blktrace_cat { -+ BLK_TC_READ = 1 << 0, /* reads */ -+ BLK_TC_WRITE = 1 << 1, /* writes */ -+ BLK_TC_BARRIER = 1 << 2, /* barrier */ -+ BLK_TC_SYNC = 1 << 3, /* barrier */ -+ BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ -+ BLK_TC_REQUEUE = 1 << 5, /* requeueing */ -+ BLK_TC_ISSUE = 1 << 6, /* issue */ -+ BLK_TC_COMPLETE = 1 << 7, /* completions */ -+ BLK_TC_FS = 1 << 8, /* fs requests */ -+ BLK_TC_PC = 1 << 9, /* pc requests */ -+ BLK_TC_NOTIFY = 1 << 10, /* special message */ -+ -+ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ -+}; -+ -+#define BLK_TC_SHIFT (16) -+#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) -+ -+/* -+ * Basic trace actions -+ */ -+enum blktrace_act { -+ __BLK_TA_QUEUE = 1, /* queued */ -+ __BLK_TA_BACKMERGE, /* back merged to existing rq */ -+ __BLK_TA_FRONTMERGE, /* front merge to existing rq */ -+ __BLK_TA_GETRQ, /* allocated new request */ -+ __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ -+ __BLK_TA_REQUEUE, /* request requeued */ -+ __BLK_TA_ISSUE, /* sent to driver */ -+ __BLK_TA_COMPLETE, /* completed by driver */ -+ __BLK_TA_PLUG, /* queue was plugged */ -+ __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ -+ __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ -+ __BLK_TA_INSERT, /* insert request */ -+ __BLK_TA_SPLIT, /* bio was split */ -+ __BLK_TA_BOUNCE, /* bio was bounced */ -+ __BLK_TA_REMAP, /* bio was remapped */ -+}; -+ -+/* -+ * Trace actions in full. Additionally, read or write is masked -+ */ -+#define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) -+#define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) -+#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) -+#define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_SPLIT (__BLK_TA_SPLIT) -+#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) -+#define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) -+ -+#define BLK_IO_TRACE_MAGIC 0x65617400 -+#define BLK_IO_TRACE_VERSION 0x07 -+ -+/* -+ * The trace itself -+ */ -+struct blk_io_trace { -+ u32 magic; /* MAGIC << 8 | version */ -+ u32 sequence; /* event number */ -+ u64 time; /* in microseconds */ -+ u64 sector; /* disk offset */ -+ u32 bytes; /* transfer length */ -+ u32 action; /* what happened */ -+ u32 pid; /* who did it */ -+ u32 device; /* device number */ -+ u32 cpu; /* on what cpu did it happen */ -+ u16 error; /* completion error */ -+ u16 pdu_len; /* length of data after this trace */ -+}; -+ -+/* -+ * The remap event -+ */ -+struct blk_io_trace_remap { -+ u32 device; -+ u32 __pad; -+ u64 sector; -+}; -+ -+enum { -+ Blktrace_setup = 1, -+ Blktrace_running, -+ Blktrace_stopped, -+}; -+ -+struct blk_trace { -+ int trace_state; -+ struct rchan *rchan; -+ unsigned long *sequence; -+ u16 act_mask; -+ u64 start_lba; -+ u64 end_lba; -+ u32 pid; -+ u32 dev; -+ struct dentry *dir; -+ struct dentry *dropped_file; -+ atomic_t dropped; -+}; -+ -+/* -+ * User setup structure passed with BLKTRACESTART -+ */ -+struct blk_user_trace_setup { -+ char name[BDEVNAME_SIZE]; /* output */ -+ u16 act_mask; /* input */ -+ u32 buf_size; /* input */ -+ u32 buf_nr; /* input */ -+ u64 start_lba; -+ u64 end_lba; -+ u32 pid; -+}; -+ -+#if defined(CONFIG_BLK_DEV_IO_TRACE) -+extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); -+extern void blk_trace_shutdown(request_queue_t *); -+extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); -+ -+/** -+ * blk_add_trace_rq - Add a trace for a request oriented action -+ * @q: queue the io is for -+ * @rq: the source request -+ * @what: the action -+ * -+ * Description: -+ * Records an action against a request. Will log the bio offset + size. -+ * -+ **/ -+static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, -+ u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ int rw = rq->flags & 0x07; -+ -+ if (likely(!bt)) -+ return; -+ -+ if (blk_pc_request(rq)) { -+ what |= BLK_TC_ACT(BLK_TC_PC); -+ __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); -+ } else { -+ what |= BLK_TC_ACT(BLK_TC_FS); -+ __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); -+ } -+} -+ -+/** -+ * blk_add_trace_bio - Add a trace for a bio oriented action -+ * @q: queue the io is for -+ * @bio: the source bio -+ * @what: the action -+ * -+ * Description: -+ * Records an action against a bio. Will log the bio offset + size. -+ * -+ **/ -+static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, -+ u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ -+ if (likely(!bt)) -+ return; -+ -+ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); -+} -+ -+/** -+ * blk_add_trace_generic - Add a trace for a generic action -+ * @q: queue the io is for -+ * @bio: the source bio -+ * @rw: the data direction -+ * @what: the action -+ * -+ * Description: -+ * Records a simple trace -+ * -+ **/ -+static inline void blk_add_trace_generic(struct request_queue *q, -+ struct bio *bio, int rw, u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ -+ if (likely(!bt)) -+ return; -+ -+ if (bio) -+ blk_add_trace_bio(q, bio, what); -+ else -+ __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); -+} -+ -+/** -+ * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload -+ * @q: queue the io is for -+ * @what: the action -+ * @bio: the source bio -+ * @pdu: the integer payload -+ * -+ * Description: -+ * Adds a trace with some integer payload. This might be an unplug -+ * option given as the action, with the depth at unplug time given -+ * as the payload -+ * -+ **/ -+static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, -+ struct bio *bio, unsigned int pdu) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ u64 rpdu = cpu_to_be64(pdu); -+ -+ if (likely(!bt)) -+ return; -+ -+ if (bio) -+ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); -+ else -+ __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); -+} -+ -+/** -+ * blk_add_trace_remap - Add a trace for a remap operation -+ * @q: queue the io is for -+ * @bio: the source bio -+ * @dev: target device -+ * @from: source sector -+ * @to: target sector -+ * -+ * Description: -+ * Device mapper or raid target sometimes need to split a bio because -+ * it spans a stripe (or similar). Add a trace for that action. -+ * -+ **/ -+static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, -+ dev_t dev, sector_t from, sector_t to) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ struct blk_io_trace_remap r; -+ -+ if (likely(!bt)) -+ return; -+ -+ r.device = cpu_to_be32(dev); -+ r.sector = cpu_to_be64(to); -+ -+ __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); -+} -+ -+#else /* !CONFIG_BLK_DEV_IO_TRACE */ -+#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) -+#define blk_trace_shutdown(q) do { } while (0) -+#define blk_add_trace_rq(q, rq, what) do { } while (0) -+#define blk_add_trace_bio(q, rq, what) do { } while (0) -+#define blk_add_trace_generic(q, rq, rw, what) do { } while (0) -+#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) -+#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) -+#endif /* CONFIG_BLK_DEV_IO_TRACE */ -+ -+#endif -diff --git a/include/linux/compat_ioctl.h b/include/linux/compat_ioctl.h -index 8fad50f..a3ed64b 100644 ---- a/include/linux/compat_ioctl.h -+++ b/include/linux/compat_ioctl.h -@@ -97,6 +97,10 @@ COMPATIBLE_IOCTL(BLKRRPART) - COMPATIBLE_IOCTL(BLKFLSBUF) - COMPATIBLE_IOCTL(BLKSECTSET) - COMPATIBLE_IOCTL(BLKSSZGET) -+COMPATIBLE_IOCTL(BLKTRACESTART) -+COMPATIBLE_IOCTL(BLKTRACESTOP) -+COMPATIBLE_IOCTL(BLKTRACESETUP) -+COMPATIBLE_IOCTL(BLKTRACETEARDOWN) - ULONG_IOCTL(BLKRASET) - ULONG_IOCTL(BLKFRASET) - /* RAID */ -diff --git a/include/linux/fs.h b/include/linux/fs.h -index e059da9..c7a63cd 100644 ---- a/include/linux/fs.h -+++ b/include/linux/fs.h -@@ -196,6 +196,10 @@ extern int dir_notify_enable; - #define BLKBSZGET _IOR(0x12,112,size_t) - #define BLKBSZSET _IOW(0x12,113,size_t) - #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ -+#define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) -+#define BLKTRACESTART _IO(0x12,116) -+#define BLKTRACESTOP _IO(0x12,117) -+#define BLKTRACETEARDOWN _IO(0x12,118) - - #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ - #define FIBMAP _IO(0x00,1) /* bmap access */ -diff --git a/include/linux/relay.h b/include/linux/relay.h -new file mode 100644 -index 0000000..0b456ec ---- /dev/null -+++ b/include/linux/relay.h -@@ -0,0 +1,282 @@ -+/* -+ * linux/include/linux/relay.h -+ * -+ * Copyright (C) 2002, 2003 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp -+ * Copyright (C) 1999, 2000, 2001, 2002 - Karim Yaghmour (karim@opersys.com) -+ * -+ * CONFIG_RELAY definitions and declarations -+ */ -+ -+#ifndef _LINUX_RELAY_H -+#define _LINUX_RELAY_H -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+/* Needs a _much_ better name... */ -+#define FIX_SIZE(x) ((((x) - 1) & PAGE_MASK) + PAGE_SIZE) -+ -+/* -+ * Tracks changes to rchan/rchan_buf structs -+ */ -+#define RELAYFS_CHANNEL_VERSION 6 -+ -+/* -+ * Per-cpu relay channel buffer -+ */ -+struct rchan_buf -+{ -+ void *start; /* start of channel buffer */ -+ void *data; /* start of current sub-buffer */ -+ size_t offset; /* current offset into sub-buffer */ -+ size_t subbufs_produced; /* count of sub-buffers produced */ -+ size_t subbufs_consumed; /* count of sub-buffers consumed */ -+ struct rchan *chan; /* associated channel */ -+ wait_queue_head_t read_wait; /* reader wait queue */ -+ struct work_struct wake_readers; /* reader wake-up work struct */ -+ struct dentry *dentry; /* channel file dentry */ -+ struct kref kref; /* channel buffer refcount */ -+ struct page **page_array; /* array of current buffer pages */ -+ unsigned int page_count; /* number of current buffer pages */ -+ unsigned int finalized; /* buffer has been finalized */ -+ size_t *padding; /* padding counts per sub-buffer */ -+ size_t prev_padding; /* temporary variable */ -+ size_t bytes_consumed; /* bytes consumed in cur read subbuf */ -+ unsigned int cpu; /* this buf's cpu */ -+ unsigned int poll_flags; -+} ____cacheline_aligned; -+ -+/* -+ * Relay channel data structure -+ */ -+struct rchan -+{ -+ u32 version; /* the version of this struct */ -+ size_t subbuf_size; /* sub-buffer size */ -+ size_t n_subbufs; /* number of sub-buffers per buffer */ -+ size_t alloc_size; /* total buffer size allocated */ -+ struct rchan_callbacks *cb; /* client callbacks */ -+ struct kref kref; /* channel refcount */ -+ void *private_data; /* for user-defined data */ -+ size_t last_toobig; /* tried to log event > subbuf size */ -+ struct rchan_buf *buf[NR_CPUS]; /* per-cpu channel buffers */ -+}; -+ -+/* -+ * Relay channel client callbacks -+ */ -+struct rchan_callbacks -+{ -+ /* -+ * subbuf_start - called on buffer-switch to a new sub-buffer -+ * @buf: the channel buffer containing the new sub-buffer -+ * @subbuf: the start of the new sub-buffer -+ * @prev_subbuf: the start of the previous sub-buffer -+ * @prev_padding: unused space at the end of previous sub-buffer -+ * -+ * The client should return 1 to continue logging, 0 to stop -+ * logging. -+ * -+ * NOTE: subbuf_start will also be invoked when the buffer is -+ * created, so that the first sub-buffer can be initialized -+ * if necessary. In this case, prev_subbuf will be NULL. -+ * -+ * NOTE: the client can reserve bytes at the beginning of the new -+ * sub-buffer by calling subbuf_start_reserve() in this callback. -+ */ -+ int (*subbuf_start) (struct rchan_buf *buf, -+ void *subbuf, -+ void *prev_subbuf, -+ size_t prev_padding); -+ -+ /* -+ * buf_mapped - relay buffer mmap notification -+ * @buf: the channel buffer -+ * @filp: relay file pointer -+ * -+ * Called when a relay file is successfully mmapped -+ */ -+ void (*buf_mapped)(struct rchan_buf *buf, -+ struct file *filp); -+ -+ /* -+ * buf_unmapped - relay buffer unmap notification -+ * @buf: the channel buffer -+ * @filp: relay file pointer -+ * -+ * Called when a relay file is successfully unmapped -+ */ -+ void (*buf_unmapped)(struct rchan_buf *buf, -+ struct file *filp); -+ /* -+ * create_buf_file - create file to represent a relay channel buffer -+ * @filename: the name of the file to create -+ * @parent: the parent of the file to create -+ * @mode: the mode of the file to create -+ * @buf: the channel buffer -+ * @is_global: outparam - set non-zero if the buffer should be global -+ * -+ * Called during relay_open(), once for each per-cpu buffer, -+ * to allow the client to create a file to be used to -+ * represent the corresponding channel buffer. If the file is -+ * created outside of relay, the parent must also exist in -+ * that filesystem. -+ * -+ * The callback should return the dentry of the file created -+ * to represent the relay buffer. -+ * -+ * Setting the is_global outparam to a non-zero value will -+ * cause relay_open() to create a single global buffer rather -+ * than the default set of per-cpu buffers. -+ * -+ * See Documentation/filesystems/relayfs.txt for more info. -+ */ -+ struct dentry *(*create_buf_file)(const char *filename, -+ struct dentry *parent, -+ int mode, -+ struct rchan_buf *buf, -+ int *is_global); -+ -+ /* -+ * remove_buf_file - remove file representing a relay channel buffer -+ * @dentry: the dentry of the file to remove -+ * -+ * Called during relay_close(), once for each per-cpu buffer, -+ * to allow the client to remove a file used to represent a -+ * channel buffer. -+ * -+ * The callback should return 0 if successful, negative if not. -+ */ -+ int (*remove_buf_file)(struct dentry *dentry); -+}; -+ -+/* -+ * CONFIG_RELAY kernel API, kernel/relay.c -+ */ -+ -+struct rchan *relay_open(const char *base_filename, -+ struct dentry *parent, -+ size_t subbuf_size, -+ size_t n_subbufs, -+ struct rchan_callbacks *cb); -+extern void relay_close(struct rchan *chan); -+extern void relay_flush(struct rchan *chan); -+extern void relay_subbufs_consumed(struct rchan *chan, -+ unsigned int cpu, -+ size_t consumed); -+extern void relay_reset(struct rchan *chan); -+extern int relay_buf_full(struct rchan_buf *buf); -+ -+extern size_t relay_switch_subbuf(struct rchan_buf *buf, -+ size_t length); -+ -+/** -+ * relay_write - write data into the channel -+ * @chan: relay channel -+ * @data: data to be written -+ * @length: number of bytes to write -+ * -+ * Writes data into the current cpu's channel buffer. -+ * -+ * Protects the buffer by disabling interrupts. Use this -+ * if you might be logging from interrupt context. Try -+ * __relay_write() if you know you won't be logging from -+ * interrupt context. -+ */ -+static inline void relay_write(struct rchan *chan, -+ const void *data, -+ size_t length) -+{ -+ unsigned long flags; -+ struct rchan_buf *buf; -+ -+ local_irq_save(flags); -+ buf = chan->buf[smp_processor_id()]; -+ if (unlikely(buf->offset + length > chan->subbuf_size)) -+ length = relay_switch_subbuf(buf, length); -+ memcpy(buf->data + buf->offset, data, length); -+ buf->offset += length; -+ local_irq_restore(flags); -+} -+ -+/** -+ * __relay_write - write data into the channel -+ * @chan: relay channel -+ * @data: data to be written -+ * @length: number of bytes to write -+ * -+ * Writes data into the current cpu's channel buffer. -+ * -+ * Protects the buffer by disabling preemption. Use -+ * relay_write() if you might be logging from interrupt -+ * context. -+ */ -+static inline void __relay_write(struct rchan *chan, -+ const void *data, -+ size_t length) -+{ -+ struct rchan_buf *buf; -+ -+ buf = chan->buf[get_cpu()]; -+ if (unlikely(buf->offset + length > buf->chan->subbuf_size)) -+ length = relay_switch_subbuf(buf, length); -+ memcpy(buf->data + buf->offset, data, length); -+ buf->offset += length; -+ put_cpu(); -+} -+ -+/** -+ * relay_reserve - reserve slot in channel buffer -+ * @chan: relay channel -+ * @length: number of bytes to reserve -+ * -+ * Returns pointer to reserved slot, NULL if full. -+ * -+ * Reserves a slot in the current cpu's channel buffer. -+ * Does not protect the buffer at all - caller must provide -+ * appropriate synchronization. -+ */ -+static inline void *relay_reserve(struct rchan *chan, size_t length) -+{ -+ void *reserved; -+ struct rchan_buf *buf = chan->buf[smp_processor_id()]; -+ -+ if (unlikely(buf->offset + length > buf->chan->subbuf_size)) { -+ length = relay_switch_subbuf(buf, length); -+ if (!length) -+ return NULL; -+ } -+ reserved = buf->data + buf->offset; -+ buf->offset += length; -+ -+ return reserved; -+} -+ -+/** -+ * subbuf_start_reserve - reserve bytes at the start of a sub-buffer -+ * @buf: relay channel buffer -+ * @length: number of bytes to reserve -+ * -+ * Helper function used to reserve bytes at the beginning of -+ * a sub-buffer in the subbuf_start() callback. -+ */ -+static inline void subbuf_start_reserve(struct rchan_buf *buf, -+ size_t length) -+{ -+ BUG_ON(length >= buf->chan->subbuf_size - 1); -+ buf->offset = length; -+} -+ -+/* -+ * exported relay file operations, kernel/relay.c -+ */ -+extern struct file_operations relay_file_operations; -+ -+#endif /* _LINUX_RELAY_H */ -+ -diff --git a/include/linux/sched.h b/include/linux/sched.h -index b6f51e3..d9d465b 100644 ---- a/include/linux/sched.h -+++ b/include/linux/sched.h -@@ -705,6 +705,7 @@ struct task_struct { - prio_array_t *array; - - unsigned short ioprio; -+ unsigned int btrace_seq; - - unsigned long sleep_avg; - unsigned long long timestamp, last_ran; -diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h -index 392da5a..36a078e 100644 ---- a/include/linux/sysfs.h -+++ b/include/linux/sysfs.h -@@ -44,6 +44,16 @@ struct attribute_group { - .show = _name##_show, \ - } - -+#define __ATTR_RELAY(_name,_buffer_size,_nr_buffers) { \ -+ .attr = { \ -+ .owner = THIS_MODULE, \ -+ .name = __stringify(_name), \ -+ .mode = 0400, \ -+ }, \ -+ .subbuf_size = _buffer_size, \ -+ .n_subbufs = _nr_buffers, \ -+} -+ - #define __ATTR_NULL { .attr = { .name = NULL } } - - #define attr_name(_attr) (_attr).attr.name -@@ -60,6 +70,15 @@ struct bin_attribute { - struct vm_area_struct *vma); - }; - -+struct relay_attribute { -+ struct attribute attr; -+ struct rchan *rchan; -+ struct rchan_buf *rchan_buf; -+ struct kobject *kobj; -+ size_t subbuf_size; -+ size_t n_subbufs; -+}; -+ - struct sysfs_ops { - ssize_t (*show)(struct kobject *, struct attribute *,char *); - ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t); -@@ -81,7 +100,23 @@ struct sysfs_dirent { - #define SYSFS_KOBJ_ATTR 0x0004 - #define SYSFS_KOBJ_BIN_ATTR 0x0008 - #define SYSFS_KOBJ_LINK 0x0020 --#define SYSFS_NOT_PINNED (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR | SYSFS_KOBJ_LINK) -+#define SYSFS_KOBJ_RELAY_ATTR 0x0040 -+#define SYSFS_NOT_PINNED (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR | \ -+ SYSFS_KOBJ_LINK | SYSFS_KOBJ_RELAY_ATTR) -+ -+#if defined(CONFIG_RELAY) && defined(CONFIG_SYSFS) -+int sysfs_create_relay_file(struct kobject *, struct relay_attribute *); -+void sysfs_remove_relay_file(struct kobject *, struct relay_attribute *); -+#else -+static inline int sysfs_create_relay_file(struct kobject *kobj, struct relay_attribute *attr) -+{ -+ return 0; -+} -+ -+static inline void sysfs_remove_relay_file(struct kobject *kobj, struct relay_attribute *attr) -+{ -+} -+#endif /* CONFIG_RELAY && CONFIG_SYSFS */ - - #ifdef CONFIG_SYSFS - -diff --git a/init/Kconfig b/init/Kconfig -index 38416a1..fb74fdd 100644 ---- a/init/Kconfig -+++ b/init/Kconfig -@@ -214,6 +214,17 @@ config CPUSETS - - Say N if unsure. - -+config RELAY -+ bool "Kernel->user space relay support (formerly relayfs)" -+ help -+ This option enables support for relay interface support in -+ certain file systems (such as sysfs, and trivially debugfs). -+ It is designed to provide an efficient mechanism for tools and -+ facilities to relay large amounts of data from kernel space to -+ user space. -+ -+ If unsure, say N. -+ - source "usr/Kconfig" - - config UID16 -diff --git a/kernel/Makefile b/kernel/Makefile -index 4ae0fbd..aebd7a7 100644 ---- a/kernel/Makefile -+++ b/kernel/Makefile -@@ -34,6 +34,7 @@ obj-$(CONFIG_DETECT_SOFTLOCKUP) += softl - obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ - obj-$(CONFIG_SECCOMP) += seccomp.o - obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o -+obj-$(CONFIG_RELAY) += relay.o - - ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) - # According to Alan Modra , the -fno-omit-frame-pointer is -diff --git a/kernel/fork.c b/kernel/fork.c -index fbea12d..f564e9b 100644 ---- a/kernel/fork.c -+++ b/kernel/fork.c -@@ -179,6 +179,7 @@ static struct task_struct *dup_task_stru - /* One for us, one for whoever does the "release_task()" (usually parent) */ - atomic_set(&tsk->usage,2); - atomic_set(&tsk->fs_excl, 0); -+ tsk->btrace_seq = 0; - return tsk; - } - -diff --git a/kernel/relay.c b/kernel/relay.c -new file mode 100644 -index 0000000..50edac5 ---- /dev/null -+++ b/kernel/relay.c -@@ -0,0 +1,1006 @@ -+/* -+ * Public API and common code for kernel->userspace relay file support. -+ * -+ * See Documentation/filesystems/relayfs.txt for an overview of relayfs. -+ * -+ * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp -+ * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) -+ * -+ * Moved to kernel/relay.c by Paul Mundt, 2006. -+ * -+ * This file is released under the GPL. -+ */ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+/* -+ * close() vm_op implementation for relay file mapping. -+ */ -+static void relay_file_mmap_close(struct vm_area_struct *vma) -+{ -+ struct rchan_buf *buf = vma->vm_private_data; -+ buf->chan->cb->buf_unmapped(buf, vma->vm_file); -+} -+ -+/* -+ * nopage() vm_op implementation for relay file mapping. -+ */ -+static struct page *relay_buf_nopage(struct vm_area_struct *vma, -+ unsigned long address, -+ int *type) -+{ -+ struct page *page; -+ struct rchan_buf *buf = vma->vm_private_data; -+ unsigned long offset = address - vma->vm_start; -+ -+ if (address > vma->vm_end) -+ return NOPAGE_SIGBUS; /* Disallow mremap */ -+ if (!buf) -+ return NOPAGE_OOM; -+ -+ page = vmalloc_to_page(buf->start + offset); -+ if (!page) -+ return NOPAGE_OOM; -+ get_page(page); -+ -+ if (type) -+ *type = VM_FAULT_MINOR; -+ -+ return page; -+} -+ -+/* -+ * vm_ops for relay file mappings. -+ */ -+static struct vm_operations_struct relay_file_mmap_ops = { -+ .nopage = relay_buf_nopage, -+ .close = relay_file_mmap_close, -+}; -+ -+/** -+ * relay_mmap_buf: - mmap channel buffer to process address space -+ * @buf: relay channel buffer -+ * @vma: vm_area_struct describing memory to be mapped -+ * -+ * Returns 0 if ok, negative on error -+ * -+ * Caller should already have grabbed mmap_sem. -+ */ -+int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) -+{ -+ unsigned long length = vma->vm_end - vma->vm_start; -+ struct file *filp = vma->vm_file; -+ -+ if (!buf) -+ return -EBADF; -+ -+ if (length != (unsigned long)buf->chan->alloc_size) -+ return -EINVAL; -+ -+ vma->vm_ops = &relay_file_mmap_ops; -+ vma->vm_private_data = buf; -+ buf->chan->cb->buf_mapped(buf, filp); -+ -+ return 0; -+} -+ -+/** -+ * relay_alloc_buf - allocate a channel buffer -+ * @buf: the buffer struct -+ * @size: total size of the buffer -+ * -+ * Returns a pointer to the resulting buffer, NULL if unsuccessful. The -+ * passed in size will get page aligned, if it isn't already. -+ */ -+static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size) -+{ -+ void *mem; -+ unsigned int i, j, n_pages; -+ -+ *size = PAGE_ALIGN(*size); -+ n_pages = *size >> PAGE_SHIFT; -+ -+ buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); -+ if (!buf->page_array) -+ return NULL; -+ -+ for (i = 0; i < n_pages; i++) { -+ buf->page_array[i] = alloc_page(GFP_KERNEL); -+ if (unlikely(!buf->page_array[i])) -+ goto depopulate; -+ } -+ mem = vmap(buf->page_array, n_pages, VM_MAP, PAGE_KERNEL); -+ if (!mem) -+ goto depopulate; -+ -+ memset(mem, 0, *size); -+ buf->page_count = n_pages; -+ return mem; -+ -+depopulate: -+ for (j = 0; j < i; j++) -+ __free_page(buf->page_array[j]); -+ kfree(buf->page_array); -+ return NULL; -+} -+ -+/** -+ * relay_create_buf - allocate and initialize a channel buffer -+ * @alloc_size: size of the buffer to allocate -+ * @n_subbufs: number of sub-buffers in the channel -+ * -+ * Returns channel buffer if successful, NULL otherwise -+ */ -+struct rchan_buf *relay_create_buf(struct rchan *chan) -+{ -+ struct rchan_buf *buf = kcalloc(1, sizeof(struct rchan_buf), GFP_KERNEL); -+ if (!buf) -+ return NULL; -+ -+ buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL); -+ if (!buf->padding) -+ goto free_buf; -+ -+ buf->start = relay_alloc_buf(buf, &chan->alloc_size); -+ if (!buf->start) -+ goto free_buf; -+ -+ buf->chan = chan; -+ kref_get(&buf->chan->kref); -+ return buf; -+ -+free_buf: -+ kfree(buf->padding); -+ kfree(buf); -+ return NULL; -+} -+ -+/** -+ * relay_destroy_channel - free the channel struct -+ * -+ * Should only be called from kref_put(). -+ */ -+void relay_destroy_channel(struct kref *kref) -+{ -+ struct rchan *chan = container_of(kref, struct rchan, kref); -+ kfree(chan); -+} -+ -+/** -+ * relay_destroy_buf - destroy an rchan_buf struct and associated buffer -+ * @buf: the buffer struct -+ */ -+void relay_destroy_buf(struct rchan_buf *buf) -+{ -+ struct rchan *chan = buf->chan; -+ unsigned int i; -+ -+ if (likely(buf->start)) { -+ vunmap(buf->start); -+ for (i = 0; i < buf->page_count; i++) -+ __free_page(buf->page_array[i]); -+ kfree(buf->page_array); -+ } -+ kfree(buf->padding); -+ kfree(buf); -+ kref_put(&chan->kref, relay_destroy_channel); -+} -+ -+/** -+ * relay_remove_buf - remove a channel buffer -+ * -+ * Removes the file from the fileystem, which also frees the -+ * rchan_buf_struct and the channel buffer. Should only be called from -+ * kref_put(). -+ */ -+void relay_remove_buf(struct kref *kref) -+{ -+ struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref); -+ buf->chan->cb->remove_buf_file(buf->dentry); -+ relay_destroy_buf(buf); -+} -+ -+/** -+ * relay_buf_empty - boolean, is the channel buffer empty? -+ * @buf: channel buffer -+ * -+ * Returns 1 if the buffer is empty, 0 otherwise. -+ */ -+int relay_buf_empty(struct rchan_buf *buf) -+{ -+ return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1; -+} -+EXPORT_SYMBOL_GPL(relay_buf_empty); -+ -+/** -+ * relay_buf_full - boolean, is the channel buffer full? -+ * @buf: channel buffer -+ * -+ * Returns 1 if the buffer is full, 0 otherwise. -+ */ -+int relay_buf_full(struct rchan_buf *buf) -+{ -+ size_t ready = buf->subbufs_produced - buf->subbufs_consumed; -+ return (ready >= buf->chan->n_subbufs) ? 1 : 0; -+} -+EXPORT_SYMBOL_GPL(relay_buf_full); -+ -+/* -+ * High-level relay kernel API and associated functions. -+ */ -+ -+/* -+ * rchan_callback implementations defining default channel behavior. Used -+ * in place of corresponding NULL values in client callback struct. -+ */ -+ -+/* -+ * subbuf_start() default callback. Does nothing. -+ */ -+static int subbuf_start_default_callback (struct rchan_buf *buf, -+ void *subbuf, -+ void *prev_subbuf, -+ size_t prev_padding) -+{ -+ if (relay_buf_full(buf)) -+ return 0; -+ -+ return 1; -+} -+ -+/* -+ * buf_mapped() default callback. Does nothing. -+ */ -+static void buf_mapped_default_callback(struct rchan_buf *buf, -+ struct file *filp) -+{ -+} -+ -+/* -+ * buf_unmapped() default callback. Does nothing. -+ */ -+static void buf_unmapped_default_callback(struct rchan_buf *buf, -+ struct file *filp) -+{ -+} -+ -+/* -+ * create_buf_file_create() default callback. Does nothing. -+ */ -+static struct dentry *create_buf_file_default_callback(const char *filename, -+ struct dentry *parent, -+ int mode, -+ struct rchan_buf *buf, -+ int *is_global) -+{ -+ return NULL; -+} -+ -+/* -+ * remove_buf_file() default callback. Does nothing. -+ */ -+static int remove_buf_file_default_callback(struct dentry *dentry) -+{ -+ return -EINVAL; -+} -+ -+/* relay channel default callbacks */ -+static struct rchan_callbacks default_channel_callbacks = { -+ .subbuf_start = subbuf_start_default_callback, -+ .buf_mapped = buf_mapped_default_callback, -+ .buf_unmapped = buf_unmapped_default_callback, -+ .create_buf_file = create_buf_file_default_callback, -+ .remove_buf_file = remove_buf_file_default_callback, -+}; -+ -+/** -+ * wakeup_readers - wake up readers waiting on a channel -+ * @private: the channel buffer -+ * -+ * This is the work function used to defer reader waking. The -+ * reason waking is deferred is that calling directly from write -+ * causes problems if you're writing from say the scheduler. -+ */ -+static void wakeup_readers(void *private) -+{ -+ struct rchan_buf *buf = private; -+ wake_up_interruptible(&buf->read_wait); -+} -+ -+/** -+ * __relay_reset - reset a channel buffer -+ * @buf: the channel buffer -+ * @init: 1 if this is a first-time initialization -+ * -+ * See relay_reset for description of effect. -+ */ -+static inline void __relay_reset(struct rchan_buf *buf, unsigned int init) -+{ -+ size_t i; -+ -+ if (init) { -+ init_waitqueue_head(&buf->read_wait); -+ kref_init(&buf->kref); -+ INIT_WORK(&buf->wake_readers, NULL, NULL); -+ } else { -+ cancel_delayed_work(&buf->wake_readers); -+ flush_scheduled_work(); -+ } -+ -+ buf->subbufs_produced = 0; -+ buf->subbufs_consumed = 0; -+ buf->bytes_consumed = 0; -+ buf->finalized = 0; -+ buf->data = buf->start; -+ buf->offset = 0; -+ -+ for (i = 0; i < buf->chan->n_subbufs; i++) -+ buf->padding[i] = 0; -+ -+ buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0); -+} -+ -+/** -+ * relay_reset - reset the channel -+ * @chan: the channel -+ * -+ * This has the effect of erasing all data from all channel buffers -+ * and restarting the channel in its initial state. The buffers -+ * are not freed, so any mappings are still in effect. -+ * -+ * NOTE: Care should be taken that the channel isn't actually -+ * being used by anything when this call is made. -+ */ -+void relay_reset(struct rchan *chan) -+{ -+ unsigned int i; -+ struct rchan_buf *prev = NULL; -+ -+ if (!chan) -+ return; -+ -+ for (i = 0; i < NR_CPUS; i++) { -+ if (!chan->buf[i] || chan->buf[i] == prev) -+ break; -+ __relay_reset(chan->buf[i], 0); -+ prev = chan->buf[i]; -+ } -+} -+EXPORT_SYMBOL_GPL(relay_reset); -+ -+/** -+ * relay_open_buf - create a new relay channel buffer -+ * -+ * Internal - used by relay_open(). -+ */ -+static struct rchan_buf *relay_open_buf(struct rchan *chan, -+ const char *filename, -+ struct dentry *parent, -+ int *is_global) -+{ -+ struct rchan_buf *buf; -+ struct dentry *dentry; -+ -+ if (*is_global) -+ return chan->buf[0]; -+ -+ buf = relay_create_buf(chan); -+ if (!buf) -+ return NULL; -+ -+ /* Create file in fs */ -+ dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR, -+ buf, is_global); -+ if (!dentry) { -+ relay_destroy_buf(buf); -+ return NULL; -+ } -+ -+ buf->dentry = dentry; -+ __relay_reset(buf, 1); -+ -+ return buf; -+} -+ -+/** -+ * relay_close_buf - close a channel buffer -+ * @buf: channel buffer -+ * -+ * Marks the buffer finalized and restores the default callbacks. -+ * The channel buffer and channel buffer data structure are then freed -+ * automatically when the last reference is given up. -+ */ -+static inline void relay_close_buf(struct rchan_buf *buf) -+{ -+ buf->finalized = 1; -+ cancel_delayed_work(&buf->wake_readers); -+ flush_scheduled_work(); -+ kref_put(&buf->kref, relay_remove_buf); -+} -+ -+static inline void setup_callbacks(struct rchan *chan, -+ struct rchan_callbacks *cb) -+{ -+ if (!cb) { -+ chan->cb = &default_channel_callbacks; -+ return; -+ } -+ -+ if (!cb->subbuf_start) -+ cb->subbuf_start = subbuf_start_default_callback; -+ if (!cb->buf_mapped) -+ cb->buf_mapped = buf_mapped_default_callback; -+ if (!cb->buf_unmapped) -+ cb->buf_unmapped = buf_unmapped_default_callback; -+ if (!cb->create_buf_file) -+ cb->create_buf_file = create_buf_file_default_callback; -+ if (!cb->remove_buf_file) -+ cb->remove_buf_file = remove_buf_file_default_callback; -+ chan->cb = cb; -+} -+ -+/** -+ * relay_open - create a new relay channel -+ * @base_filename: base name of files to create -+ * @parent: dentry of parent directory, NULL for root directory -+ * @subbuf_size: size of sub-buffers -+ * @n_subbufs: number of sub-buffers -+ * @cb: client callback functions -+ * -+ * Returns channel pointer if successful, NULL otherwise. -+ * -+ * Creates a channel buffer for each cpu using the sizes and -+ * attributes specified. The created channel buffer files -+ * will be named base_filename0...base_filenameN-1. File -+ * permissions will be S_IRUSR. -+ */ -+struct rchan *relay_open(const char *base_filename, -+ struct dentry *parent, -+ size_t subbuf_size, -+ size_t n_subbufs, -+ struct rchan_callbacks *cb) -+{ -+ unsigned int i; -+ struct rchan *chan; -+ char *tmpname; -+ int is_global = 0; -+ -+ if (!base_filename) -+ return NULL; -+ -+ if (!(subbuf_size && n_subbufs)) -+ return NULL; -+ -+ chan = kcalloc(1, sizeof(struct rchan), GFP_KERNEL); -+ if (!chan) -+ return NULL; -+ -+ chan->version = RELAYFS_CHANNEL_VERSION; -+ chan->n_subbufs = n_subbufs; -+ chan->subbuf_size = subbuf_size; -+ chan->alloc_size = FIX_SIZE(subbuf_size * n_subbufs); -+ setup_callbacks(chan, cb); -+ kref_init(&chan->kref); -+ -+ tmpname = kmalloc(NAME_MAX + 1, GFP_KERNEL); -+ if (!tmpname) -+ goto free_chan; -+ -+ for_each_online_cpu(i) { -+ sprintf(tmpname, "%s%d", base_filename, i); -+ chan->buf[i] = relay_open_buf(chan, tmpname, parent, -+ &is_global); -+ chan->buf[i]->cpu = i; -+ if (!chan->buf[i]) -+ goto free_bufs; -+ } -+ -+ kfree(tmpname); -+ return chan; -+ -+free_bufs: -+ for (i = 0; i < NR_CPUS; i++) { -+ if (!chan->buf[i]) -+ break; -+ relay_close_buf(chan->buf[i]); -+ if (is_global) -+ break; -+ } -+ kfree(tmpname); -+ -+free_chan: -+ kref_put(&chan->kref, relay_destroy_channel); -+ return NULL; -+} -+EXPORT_SYMBOL_GPL(relay_open); -+ -+/** -+ * relay_switch_subbuf - switch to a new sub-buffer -+ * @buf: channel buffer -+ * @length: size of current event -+ * -+ * Returns either the length passed in or 0 if full. -+ * -+ * Performs sub-buffer-switch tasks such as invoking callbacks, -+ * updating padding counts, waking up readers, etc. -+ */ -+size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length) -+{ -+ void *old, *new; -+ size_t old_subbuf, new_subbuf; -+ -+ if (unlikely(length > buf->chan->subbuf_size)) -+ goto toobig; -+ -+ if (buf->offset != buf->chan->subbuf_size + 1) { -+ buf->prev_padding = buf->chan->subbuf_size - buf->offset; -+ old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; -+ buf->padding[old_subbuf] = buf->prev_padding; -+ buf->subbufs_produced++; -+ buf->dentry->d_inode->i_size += buf->chan->subbuf_size - -+ buf->padding[old_subbuf]; -+ buf->poll_flags = POLLMSG; -+ smp_mb(); -+ if (waitqueue_active(&buf->read_wait)) { -+ PREPARE_WORK(&buf->wake_readers, wakeup_readers, buf); -+ schedule_delayed_work(&buf->wake_readers, 1); -+ } -+ } -+ -+ old = buf->data; -+ new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; -+ new = buf->start + new_subbuf * buf->chan->subbuf_size; -+ buf->offset = 0; -+ if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { -+ buf->offset = buf->chan->subbuf_size + 1; -+ return 0; -+ } -+ buf->data = new; -+ buf->padding[new_subbuf] = 0; -+ -+ if (unlikely(length + buf->offset > buf->chan->subbuf_size)) -+ goto toobig; -+ -+ return length; -+ -+toobig: -+ buf->chan->last_toobig = length; -+ return 0; -+} -+EXPORT_SYMBOL_GPL(relay_switch_subbuf); -+ -+/** -+ * relay_subbufs_consumed - update the buffer's sub-buffers-consumed count -+ * @chan: the channel -+ * @cpu: the cpu associated with the channel buffer to update -+ * @subbufs_consumed: number of sub-buffers to add to current buf's count -+ * -+ * Adds to the channel buffer's consumed sub-buffer count. -+ * subbufs_consumed should be the number of sub-buffers newly consumed, -+ * not the total consumed. -+ * -+ * NOTE: kernel clients don't need to call this function if the channel -+ * mode is 'overwrite'. -+ */ -+void relay_subbufs_consumed(struct rchan *chan, -+ unsigned int cpu, -+ size_t subbufs_consumed) -+{ -+ struct rchan_buf *buf; -+ -+ if (!chan) -+ return; -+ -+ if (cpu >= NR_CPUS || !chan->buf[cpu]) -+ return; -+ -+ buf = chan->buf[cpu]; -+ buf->subbufs_consumed += subbufs_consumed; -+ if (buf->subbufs_consumed > buf->subbufs_produced) -+ buf->subbufs_consumed = buf->subbufs_produced; -+} -+EXPORT_SYMBOL_GPL(relay_subbufs_consumed); -+ -+/** -+ * relay_close - close the channel -+ * @chan: the channel -+ * -+ * Closes all channel buffers and frees the channel. -+ */ -+void relay_close(struct rchan *chan) -+{ -+ unsigned int i; -+ struct rchan_buf *prev = NULL; -+ -+ if (!chan) -+ return; -+ -+ for (i = 0; i < NR_CPUS; i++) { -+ if (!chan->buf[i] || chan->buf[i] == prev) -+ break; -+ relay_close_buf(chan->buf[i]); -+ prev = chan->buf[i]; -+ } -+ -+ if (chan->last_toobig) -+ printk(KERN_WARNING "relay: one or more items not logged " -+ "[item size (%Zd) > sub-buffer size (%Zd)]\n", -+ chan->last_toobig, chan->subbuf_size); -+ -+ kref_put(&chan->kref, relay_destroy_channel); -+} -+EXPORT_SYMBOL_GPL(relay_close); -+ -+/** -+ * relay_flush - close the channel -+ * @chan: the channel -+ * -+ * Flushes all channel buffers i.e. forces buffer switch. -+ */ -+void relay_flush(struct rchan *chan) -+{ -+ unsigned int i; -+ struct rchan_buf *prev = NULL; -+ -+ if (!chan) -+ return; -+ -+ for (i = 0; i < NR_CPUS; i++) { -+ if (!chan->buf[i] || chan->buf[i] == prev) -+ break; -+ relay_switch_subbuf(chan->buf[i], 0); -+ prev = chan->buf[i]; -+ } -+} -+EXPORT_SYMBOL_GPL(relay_flush); -+ -+/** -+ * relay_file_open - open file op for relay files -+ * @inode: the inode -+ * @filp: the file -+ * -+ * Increments the channel buffer refcount. -+ */ -+static int relay_file_open(struct inode *inode, struct file *filp) -+{ -+ struct rchan_buf *buf = inode->u.generic_ip; -+ kref_get(&buf->kref); -+ filp->private_data = buf; -+ -+ return 0; -+} -+ -+/** -+ * relay_file_mmap - mmap file op for relay files -+ * @filp: the file -+ * @vma: the vma describing what to map -+ * -+ * Calls upon relay_mmap_buf to map the file into user space. -+ */ -+static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) -+{ -+ struct rchan_buf *buf = filp->private_data; -+ return relay_mmap_buf(buf, vma); -+} -+ -+/** -+ * relay_file_poll - poll file op for relay files -+ * @filp: the file -+ * @wait: poll table -+ * -+ * Poll implemention. -+ */ -+static unsigned int relay_file_poll(struct file *filp, poll_table *wait) -+{ -+ unsigned int mask = 0; -+ struct rchan_buf *buf = filp->private_data; -+ -+ if (buf->finalized) -+ return POLLERR; -+ -+ if (filp->f_mode & FMODE_READ) { -+ poll_wait(filp, &buf->read_wait, wait); -+ if (!relay_buf_empty(buf)) -+ mask |= POLLIN | POLLRDNORM | buf->poll_flags; -+ buf->poll_flags = 0; -+ } -+ -+ return mask; -+} -+ -+/** -+ * relay_file_release - release file op for relay files -+ * @inode: the inode -+ * @filp: the file -+ * -+ * Decrements the channel refcount, as the filesystem is -+ * no longer using it. -+ */ -+static int relay_file_release(struct inode *inode, struct file *filp) -+{ -+ struct rchan_buf *buf = filp->private_data; -+ kref_put(&buf->kref, relay_remove_buf); -+ -+ return 0; -+} -+ -+/** -+ * relay_file_read_consume - update the consumed count for the buffer -+ */ -+static void relay_file_read_consume(struct rchan_buf *buf, -+ size_t read_pos, -+ size_t bytes_consumed) -+{ -+ size_t subbuf_size = buf->chan->subbuf_size; -+ size_t n_subbufs = buf->chan->n_subbufs; -+ size_t read_subbuf; -+ -+ if (buf->bytes_consumed + bytes_consumed > subbuf_size) { -+ relay_subbufs_consumed(buf->chan, buf->cpu, 1); -+ buf->bytes_consumed = 0; -+ } -+ -+ buf->bytes_consumed += bytes_consumed; -+ read_subbuf = read_pos / buf->chan->subbuf_size; -+ if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) { -+ if ((read_subbuf == buf->subbufs_produced % n_subbufs) && -+ (buf->offset == subbuf_size)) -+ return; -+ relay_subbufs_consumed(buf->chan, buf->cpu, 1); -+ buf->bytes_consumed = 0; -+ } -+} -+ -+/** -+ * relay_file_read_avail - boolean, are there unconsumed bytes available? -+ */ -+static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos) -+{ -+ size_t subbuf_size = buf->chan->subbuf_size; -+ size_t n_subbufs = buf->chan->n_subbufs; -+ size_t produced = buf->subbufs_produced; -+ size_t consumed = buf->subbufs_consumed; -+ -+ relay_file_read_consume(buf, read_pos, 0); -+ -+ if (unlikely(buf->offset > subbuf_size)) { -+ if (produced == consumed) -+ return 0; -+ return 1; -+ } -+ -+ if (unlikely(produced - consumed >= n_subbufs)) { -+ consumed = (produced / n_subbufs) * n_subbufs; -+ buf->subbufs_consumed = consumed; -+ } -+ -+ produced = (produced % n_subbufs) * subbuf_size + buf->offset; -+ consumed = (consumed % n_subbufs) * subbuf_size + buf->bytes_consumed; -+ -+ if (consumed > produced) -+ produced += n_subbufs * subbuf_size; -+ -+ if (consumed == produced) -+ return 0; -+ -+ return 1; -+} -+ -+/** -+ * relay_file_read_subbuf_avail - return bytes available in sub-buffer -+ */ -+static size_t relay_file_read_subbuf_avail(size_t read_pos, -+ struct rchan_buf *buf) -+{ -+ size_t padding, avail = 0; -+ size_t read_subbuf, read_offset, write_subbuf, write_offset; -+ size_t subbuf_size = buf->chan->subbuf_size; -+ -+ write_subbuf = (buf->data - buf->start) / subbuf_size; -+ write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; -+ read_subbuf = read_pos / subbuf_size; -+ read_offset = read_pos % subbuf_size; -+ padding = buf->padding[read_subbuf]; -+ -+ if (read_subbuf == write_subbuf) { -+ if (read_offset + padding < write_offset) -+ avail = write_offset - (read_offset + padding); -+ } else -+ avail = (subbuf_size - padding) - read_offset; -+ -+ return avail; -+} -+ -+/** -+ * relay_file_read_start_pos - find the first available byte to read -+ * -+ * If the read_pos is in the middle of padding, return the -+ * position of the first actually available byte, otherwise -+ * return the original value. -+ */ -+static size_t relay_file_read_start_pos(size_t read_pos, -+ struct rchan_buf *buf) -+{ -+ size_t read_subbuf, padding, padding_start, padding_end; -+ size_t subbuf_size = buf->chan->subbuf_size; -+ size_t n_subbufs = buf->chan->n_subbufs; -+ -+ read_subbuf = read_pos / subbuf_size; -+ padding = buf->padding[read_subbuf]; -+ padding_start = (read_subbuf + 1) * subbuf_size - padding; -+ padding_end = (read_subbuf + 1) * subbuf_size; -+ if (read_pos >= padding_start && read_pos < padding_end) { -+ read_subbuf = (read_subbuf + 1) % n_subbufs; -+ read_pos = read_subbuf * subbuf_size; -+ } -+ -+ return read_pos; -+} -+ -+/** -+ * relay_file_read_end_pos - return the new read position -+ */ -+static size_t relay_file_read_end_pos(struct rchan_buf *buf, -+ size_t read_pos, -+ size_t count) -+{ -+ size_t read_subbuf, padding, end_pos; -+ size_t subbuf_size = buf->chan->subbuf_size; -+ size_t n_subbufs = buf->chan->n_subbufs; -+ -+ read_subbuf = read_pos / subbuf_size; -+ padding = buf->padding[read_subbuf]; -+ if (read_pos % subbuf_size + count + padding == subbuf_size) -+ end_pos = (read_subbuf + 1) * subbuf_size; -+ else -+ end_pos = read_pos + count; -+ if (end_pos >= subbuf_size * n_subbufs) -+ end_pos = 0; -+ -+ return end_pos; -+} -+ -+/** -+ * relay_file_read - read file op for relay files -+ * @filp: the file -+ * @buffer: the userspace buffer -+ * @count: number of bytes to read -+ * @ppos: position to read from -+ * -+ * Reads count bytes or the number of bytes available in the -+ * current sub-buffer being read, whichever is smaller. -+ */ -+static ssize_t relay_file_read(struct file *filp, -+ char __user *buffer, -+ size_t count, -+ loff_t *ppos) -+{ -+ struct rchan_buf *buf = filp->private_data; -+ struct inode *inode = filp->f_dentry->d_inode; -+ size_t read_start, avail; -+ ssize_t ret = 0; -+ void *from; -+ -+ mutex_lock(&inode->i_mutex); -+ if(!relay_file_read_avail(buf, *ppos)) -+ goto out; -+ -+ read_start = relay_file_read_start_pos(*ppos, buf); -+ avail = relay_file_read_subbuf_avail(read_start, buf); -+ if (!avail) -+ goto out; -+ -+ from = buf->start + read_start; -+ ret = count = min(count, avail); -+ if (copy_to_user(buffer, from, count)) { -+ ret = -EFAULT; -+ goto out; -+ } -+ relay_file_read_consume(buf, read_start, count); -+ *ppos = relay_file_read_end_pos(buf, read_start, count); -+out: -+ mutex_unlock(&inode->i_mutex); -+ return ret; -+} -+ -+static ssize_t relay_file_sendsubbuf(struct file *filp, loff_t *ppos, -+ size_t count, read_actor_t actor, -+ void *target) -+{ -+ struct rchan_buf *buf = filp->private_data; -+ read_descriptor_t desc; -+ size_t read_start, avail; -+ unsigned long pidx, poff; -+ unsigned int subbuf_pages; -+ ssize_t ret = 0; -+ -+ if (!relay_file_read_avail(buf, *ppos)) -+ return 0; -+ -+ read_start = relay_file_read_start_pos(*ppos, buf); -+ avail = relay_file_read_subbuf_avail(read_start, buf); -+ if (!avail) -+ return 0; -+ -+ count = min(count, avail); -+ -+ desc.written = 0; -+ desc.count = count; -+ desc.arg.data = target; -+ desc.error = 0; -+ -+ subbuf_pages = buf->chan->alloc_size >> PAGE_SHIFT; -+ pidx = (read_start / PAGE_SIZE) % subbuf_pages; -+ poff = read_start & ~PAGE_MASK; -+ while (count) { -+ struct page *p = buf->page_array[pidx]; -+ unsigned int len; -+ -+ len = PAGE_SIZE - poff; -+ if (len > count) -+ len = count; -+ -+ len = actor(&desc, p, poff, len); -+ -+ if (desc.error) { -+ if (!ret) -+ ret = desc.error; -+ break; -+ } -+ -+ count -= len; -+ ret += len; -+ poff = 0; -+ pidx = (pidx + 1) % subbuf_pages; -+ } -+ -+ if (ret > 0) { -+ relay_file_read_consume(buf, read_start, ret); -+ *ppos = relay_file_read_end_pos(buf, read_start, ret); -+ } -+ -+ return ret; -+} -+ -+static ssize_t relay_file_sendfile(struct file *filp, loff_t *ppos, -+ size_t count, read_actor_t actor, -+ void *target) -+{ -+ ssize_t sent = 0, ret = 0; -+ -+ if (!count) -+ return 0; -+ -+ mutex_lock(&filp->f_dentry->d_inode->i_mutex); -+ -+ do { -+ ret = relay_file_sendsubbuf(filp, ppos, count, actor, target); -+ if (ret < 0) { -+ if (!sent) -+ sent = ret; -+ break; -+ } -+ count -= ret; -+ sent += ret; -+ } while (count && ret); -+ -+ mutex_unlock(&filp->f_dentry->d_inode->i_mutex); -+ return sent; -+} -+ -+struct file_operations relay_file_operations = { -+ .open = relay_file_open, -+ .poll = relay_file_poll, -+ .mmap = relay_file_mmap, -+ .read = relay_file_read, -+ .llseek = no_llseek, -+ .release = relay_file_release, -+ .sendfile = relay_file_sendfile, -+}; -+EXPORT_SYMBOL_GPL(relay_file_operations); -diff --git a/mm/highmem.c b/mm/highmem.c -index ce2e7e8..d0ea1ee 100644 ---- a/mm/highmem.c -+++ b/mm/highmem.c -@@ -26,6 +26,7 @@ - #include - #include - #include -+#include - #include - - static mempool_t *page_pool, *isa_page_pool; -@@ -483,6 +484,8 @@ void blk_queue_bounce(request_queue_t *q - pool = isa_page_pool; - } - -+ blk_add_trace_bio(q, *bio_orig, BLK_TA_BOUNCE); -+ - /* - * slow path - */ diff --git a/kernel/blk-trace-2.6.16-rc5-git-B0 b/kernel/blk-trace-2.6.16-rc5-git-B0 new file mode 100644 index 0000000..5c42b5c --- /dev/null +++ b/kernel/blk-trace-2.6.16-rc5-git-B0 @@ -0,0 +1,4175 @@ +diff --git a/block/Kconfig b/block/Kconfig +index 377f6dd..9678364 100644 +--- a/block/Kconfig ++++ b/block/Kconfig +@@ -11,4 +11,16 @@ config LBD + your machine, or if you want to have a raid or loopback device + bigger than 2TB. Otherwise say N. + ++config BLK_DEV_IO_TRACE ++ bool "Support for tracing block io actions" ++ select RELAY ++ select DEBUG_FS ++ help ++ Say Y here, if you want to be able to trace the block layer actions ++ on a given queue. Tracing allows you to see any traffic happening ++ on a block device queue. For more information (and the user space ++ support tools needed), fetch the blktrace app from: ++ ++ git://brick.kernel.dk/data/git/blktrace.git ++ + source block/Kconfig.iosched +diff --git a/block/Makefile b/block/Makefile +index 7e4f93e..c05de0e 100644 +--- a/block/Makefile ++++ b/block/Makefile +@@ -8,3 +8,5 @@ obj-$(CONFIG_IOSCHED_NOOP) += noop-iosch + obj-$(CONFIG_IOSCHED_AS) += as-iosched.o + obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o + obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o ++ ++obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o +diff --git a/block/blktrace.c b/block/blktrace.c +new file mode 100644 +index 0000000..7c9ac33 +--- /dev/null ++++ b/block/blktrace.c +@@ -0,0 +1,533 @@ ++/* ++ * Copyright (C) 2006 Jens Axboe ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License version 2 as ++ * published by the Free Software Foundation. ++ * ++ * This program is distributed in the hope that it will be useful, ++ * but WITHOUT ANY WARRANTY; without even the implied warranty of ++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ++ * GNU General Public License for more details. ++ * ++ * You should have received a copy of the GNU General Public License ++ * along with this program; if not, write to the Free Software ++ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA ++ * ++ */ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; ++static unsigned int blktrace_seq __read_mostly = 1; ++ ++/* ++ * Send out a notify for this process, if we haven't done so since a trace ++ * started ++ */ ++static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) ++{ ++ struct blk_io_trace *t; ++ ++ t = relay_reserve(bt->rchan, sizeof(*t) + sizeof(tsk->comm)); ++ if (t) { ++ t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; ++ t->device = bt->dev; ++ t->action = BLK_TC_ACT(BLK_TC_NOTIFY); ++ t->pid = tsk->pid; ++ t->cpu = smp_processor_id(); ++ t->pdu_len = sizeof(tsk->comm); ++ memcpy((void *) t + sizeof(*t), tsk->comm, t->pdu_len); ++ tsk->btrace_seq = blktrace_seq; ++ } ++} ++ ++static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, ++ pid_t pid) ++{ ++ if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) ++ return 1; ++ if (sector < bt->start_lba || sector > bt->end_lba) ++ return 1; ++ if (bt->pid && pid != bt->pid) ++ return 1; ++ ++ return 0; ++} ++ ++/* ++ * Data direction bit lookup ++ */ ++static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; ++ ++/* ++ * Bio action bits of interest ++ */ ++static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC) }; ++ ++/* ++ * More could be added as needed, taking care to increment the decrementer ++ * to get correct indexing ++ */ ++#define trace_barrier_bit(rw) \ ++ (((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0)) ++#define trace_sync_bit(rw) \ ++ (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1)) ++ ++/* ++ * The worker for the various blk_add_trace*() types. Fills out a ++ * blk_io_trace structure and places it in a per-cpu subbuffer. ++ */ ++void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, ++ int rw, u32 what, int error, int pdu_len, void *pdu_data) ++{ ++ struct task_struct *tsk = current; ++ struct blk_io_trace *t; ++ unsigned long flags; ++ unsigned long *sequence; ++ pid_t pid; ++ int cpu; ++ ++ if (unlikely(bt->trace_state != Blktrace_running)) ++ return; ++ ++ what |= ddir_act[rw & WRITE]; ++ what |= bio_act[trace_barrier_bit(rw)]; ++ what |= bio_act[trace_sync_bit(rw)]; ++ ++ pid = tsk->pid; ++ if (unlikely(act_log_check(bt, what, sector, pid))) ++ return; ++ ++ /* ++ * A word about the locking here - we disable interrupts to reserve ++ * some space in the relay per-cpu buffer, to prevent an irq ++ * from coming in and stepping on our toes. Once reserved, it's ++ * enough to get preemption disabled to prevent read of this data ++ * before we are through filling it. get_cpu()/put_cpu() does this ++ * for us ++ */ ++ local_irq_save(flags); ++ ++ if (unlikely(tsk->btrace_seq != blktrace_seq)) ++ trace_note_tsk(bt, tsk); ++ ++ t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); ++ if (t) { ++ cpu = smp_processor_id(); ++ sequence = per_cpu_ptr(bt->sequence, cpu); ++ ++ t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; ++ t->sequence = ++(*sequence); ++ t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); ++ t->sector = sector; ++ t->bytes = bytes; ++ t->action = what; ++ t->pid = pid; ++ t->device = bt->dev; ++ t->cpu = cpu; ++ t->error = error; ++ t->pdu_len = pdu_len; ++ ++ if (pdu_len) ++ memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); ++ } ++ ++ local_irq_restore(flags); ++} ++ ++EXPORT_SYMBOL_GPL(__blk_add_trace); ++ ++static struct dentry *blk_tree_root; ++static struct mutex blk_tree_mutex; ++ ++static inline void blk_remove_root(void) ++{ ++ if (blk_tree_root) { ++ debugfs_remove(blk_tree_root); ++ blk_tree_root = NULL; ++ } ++} ++ ++static void blk_remove_tree(struct dentry *dir) ++{ ++ mutex_lock(&blk_tree_mutex); ++ debugfs_remove(dir); ++ blk_remove_root(); ++ mutex_unlock(&blk_tree_mutex); ++} ++ ++static struct dentry *blk_create_tree(const char *blk_name) ++{ ++ struct dentry *dir = NULL; ++ ++ mutex_lock(&blk_tree_mutex); ++ ++ if (!blk_tree_root) { ++ blk_tree_root = debugfs_create_dir("block", NULL); ++ if (!blk_tree_root) ++ goto err; ++ } ++ ++ dir = debugfs_create_dir(blk_name, blk_tree_root); ++ if (!dir) ++ blk_remove_root(); ++ ++err: ++ mutex_unlock(&blk_tree_mutex); ++ return dir; ++} ++ ++static void blk_trace_cleanup(struct blk_trace *bt) ++{ ++ relay_close(bt->rchan); ++ debugfs_remove(bt->dropped_file); ++ blk_remove_tree(bt->dir); ++ free_percpu(bt->sequence); ++ kfree(bt); ++} ++ ++static int blk_trace_remove(request_queue_t *q) ++{ ++ struct blk_trace *bt; ++ ++ bt = xchg(&q->blk_trace, NULL); ++ if (!bt) ++ return -EINVAL; ++ ++ if (bt->trace_state == Blktrace_setup || ++ bt->trace_state == Blktrace_stopped) ++ blk_trace_cleanup(bt); ++ ++ return 0; ++} ++ ++static int blk_dropped_open(struct inode *inode, struct file *filp) ++{ ++ filp->private_data = inode->u.generic_ip; ++ ++ return 0; ++} ++ ++static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, ++ size_t count, loff_t *ppos) ++{ ++ struct blk_trace *bt = filp->private_data; ++ char buf[16]; ++ ++ snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); ++ ++ return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); ++} ++ ++static struct file_operations blk_dropped_fops = { ++ .owner = THIS_MODULE, ++ .open = blk_dropped_open, ++ .read = blk_dropped_read, ++}; ++ ++/* ++ * Keep track of how many times we encountered a full subbuffer, to aid ++ * the user space app in telling how many lost events there were. ++ */ ++static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, ++ void *prev_subbuf, size_t prev_padding) ++{ ++ struct blk_trace *bt; ++ ++ if (!relay_buf_full(buf)) ++ return 1; ++ ++ bt = buf->chan->private_data; ++ atomic_inc(&bt->dropped); ++ return 0; ++} ++ ++static int blk_remove_buf_file_callback(struct dentry *dentry) ++{ ++ debugfs_remove(dentry); ++ return 0; ++} ++ ++static struct dentry *blk_create_buf_file_callback(const char *filename, ++ struct dentry *parent, ++ int mode, ++ struct rchan_buf *buf, ++ int *is_global) ++{ ++ return debugfs_create_file(filename, mode, parent, buf, ++ &relay_file_operations); ++} ++ ++static struct rchan_callbacks blk_relay_callbacks = { ++ .subbuf_start = blk_subbuf_start_callback, ++ .create_buf_file = blk_create_buf_file_callback, ++ .remove_buf_file = blk_remove_buf_file_callback, ++}; ++ ++/* ++ * Setup everything required to start tracing ++ */ ++static int blk_trace_setup(request_queue_t *q, struct block_device *bdev, ++ char __user *arg) ++{ ++ struct blk_user_trace_setup buts; ++ struct blk_trace *old_bt, *bt = NULL; ++ struct dentry *dir = NULL; ++ char b[BDEVNAME_SIZE]; ++ int ret, i; ++ ++ if (copy_from_user(&buts, arg, sizeof(buts))) ++ return -EFAULT; ++ ++ if (!buts.buf_size || !buts.buf_nr) ++ return -EINVAL; ++ ++ strcpy(buts.name, bdevname(bdev, b)); ++ ++ /* ++ * some device names have larger paths - convert the slashes ++ * to underscores for this to work as expected ++ */ ++ for (i = 0; i < strlen(buts.name); i++) ++ if (buts.name[i] == '/') ++ buts.name[i] = '_'; ++ ++ if (copy_to_user(arg, &buts, sizeof(buts))) ++ return -EFAULT; ++ ++ ret = -ENOMEM; ++ bt = kzalloc(sizeof(*bt), GFP_KERNEL); ++ if (!bt) ++ goto err; ++ ++ bt->sequence = alloc_percpu(unsigned long); ++ if (!bt->sequence) ++ goto err; ++ ++ ret = -ENOENT; ++ dir = blk_create_tree(buts.name); ++ if (!dir) ++ goto err; ++ ++ bt->dir = dir; ++ bt->dev = bdev->bd_dev; ++ atomic_set(&bt->dropped, 0); ++ ++ ret = -EIO; ++ bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops); ++ if (!bt->dropped_file) ++ goto err; ++ ++ bt->rchan = relay_open("trace", dir, buts.buf_size, buts.buf_nr, &blk_relay_callbacks); ++ if (!bt->rchan) ++ goto err; ++ bt->rchan->private_data = bt; ++ ++ bt->act_mask = buts.act_mask; ++ if (!bt->act_mask) ++ bt->act_mask = (u16) -1; ++ ++ bt->start_lba = buts.start_lba; ++ bt->end_lba = buts.end_lba; ++ if (!bt->end_lba) ++ bt->end_lba = -1ULL; ++ ++ bt->pid = buts.pid; ++ bt->trace_state = Blktrace_setup; ++ ++ ret = -EBUSY; ++ old_bt = xchg(&q->blk_trace, bt); ++ if (old_bt) { ++ xchg(&q->blk_trace, old_bt); ++ goto err; ++ } ++ ++ return 0; ++err: ++ if (dir) ++ blk_remove_tree(dir); ++ if (bt) { ++ if (bt->dropped_file) ++ debugfs_remove(bt->dropped_file); ++ if (bt->sequence) ++ free_percpu(bt->sequence); ++ if (bt->rchan) ++ relay_close(bt->rchan); ++ kfree(bt); ++ } ++ return ret; ++} ++ ++static int blk_trace_startstop(request_queue_t *q, int start) ++{ ++ struct blk_trace *bt; ++ int ret; ++ ++ if ((bt = q->blk_trace) == NULL) ++ return -EINVAL; ++ ++ /* ++ * For starting a trace, we can transition from a setup or stopped ++ * trace. For stopping a trace, the state must be running ++ */ ++ ret = -EINVAL; ++ if (start) { ++ if (bt->trace_state == Blktrace_setup || ++ bt->trace_state == Blktrace_stopped) { ++ blktrace_seq++; ++ smp_mb(); ++ bt->trace_state = Blktrace_running; ++ ret = 0; ++ } ++ } else { ++ if (bt->trace_state == Blktrace_running) { ++ bt->trace_state = Blktrace_stopped; ++ ret = 0; ++ } ++ } ++ ++ return ret; ++} ++ ++/** ++ * blk_trace_ioctl: - handle the ioctls associated with tracing ++ * @bdev: the block device ++ * @cmd: the ioctl cmd ++ * @arg: the argument data, if any ++ * ++ **/ ++int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) ++{ ++ request_queue_t *q; ++ int ret, start = 0; ++ ++ q = bdev_get_queue(bdev); ++ if (!q) ++ return -ENXIO; ++ ++ down(&bdev->bd_sem); ++ ++ switch (cmd) { ++ case BLKTRACESETUP: ++ ret = blk_trace_setup(q, bdev, arg); ++ break; ++ case BLKTRACESTART: ++ start = 1; ++ case BLKTRACESTOP: ++ ret = blk_trace_startstop(q, start); ++ break; ++ case BLKTRACETEARDOWN: ++ ret = blk_trace_remove(q); ++ break; ++ default: ++ ret = -ENOTTY; ++ break; ++ } ++ ++ up(&bdev->bd_sem); ++ return ret; ++} ++ ++/** ++ * blk_trace_shutdown: - stop and cleanup trace structures ++ * @q: the request queue associated with the device ++ * ++ **/ ++void blk_trace_shutdown(request_queue_t *q) ++{ ++ blk_trace_startstop(q, 0); ++ blk_trace_remove(q); ++} ++ ++/* ++ * Average offset over two calls to sched_clock() with a gettimeofday() ++ * in the middle ++ */ ++static void blk_check_time(unsigned long long *t) ++{ ++ unsigned long long a, b; ++ struct timeval tv; ++ ++ a = sched_clock(); ++ do_gettimeofday(&tv); ++ b = sched_clock(); ++ ++ *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; ++ *t -= (a + b) / 2; ++} ++ ++static void blk_trace_check_cpu_time(void *data) ++{ ++ unsigned long long *t; ++ int cpu = get_cpu(); ++ ++ t = &per_cpu(blk_trace_cpu_offset, cpu); ++ ++ /* ++ * Just call it twice, hopefully the second call will be cache hot ++ * and a little more precise ++ */ ++ blk_check_time(t); ++ blk_check_time(t); ++ ++ put_cpu(); ++} ++ ++/* ++ * Call blk_trace_check_cpu_time() on each CPU to calibrate our inter-CPU ++ * timings ++ */ ++static void blk_trace_calibrate_offsets(void) ++{ ++ unsigned long flags; ++ ++ smp_call_function(blk_trace_check_cpu_time, NULL, 1, 1); ++ local_irq_save(flags); ++ blk_trace_check_cpu_time(NULL); ++ local_irq_restore(flags); ++} ++ ++static void blk_trace_set_ht_offsets(void) ++{ ++#if defined(CONFIG_SCHED_SMT) ++ int cpu, i; ++ ++ /* ++ * now make sure HT siblings have the same time offset ++ */ ++ preempt_disable(); ++ for_each_online_cpu(cpu) { ++ unsigned long long *cpu_off, *sibling_off; ++ ++ for_each_cpu_mask(i, cpu_sibling_map[cpu]) { ++ if (i == cpu) ++ continue; ++ ++ cpu_off = &per_cpu(blk_trace_cpu_offset, cpu); ++ sibling_off = &per_cpu(blk_trace_cpu_offset, i); ++ *sibling_off = *cpu_off; ++ } ++ } ++ preempt_enable(); ++#endif ++} ++ ++static __init int blk_trace_init(void) ++{ ++ mutex_init(&blk_tree_mutex); ++ blk_trace_calibrate_offsets(); ++ blk_trace_set_ht_offsets(); ++ ++ return 0; ++} ++ ++module_init(blk_trace_init); ++ +diff --git a/block/elevator.c b/block/elevator.c +index 24b702d..0c9fafe 100644 +--- a/block/elevator.c ++++ b/block/elevator.c +@@ -33,6 +33,7 @@ + #include + #include + #include ++#include + + #include + +@@ -315,6 +316,8 @@ void elv_insert(request_queue_t *q, stru + struct list_head *pos; + unsigned ordseq; + ++ blk_add_trace_rq(q, rq, BLK_TA_INSERT); ++ + rq->q = q; + + switch (where) { +@@ -481,6 +484,7 @@ struct request *elv_next_request(request + * not be passed by new incoming requests + */ + rq->flags |= REQ_STARTED; ++ blk_add_trace_rq(q, rq, BLK_TA_ISSUE); + } + + if (!q->boundary_rq || q->boundary_rq == rq) { +diff --git a/block/ioctl.c b/block/ioctl.c +index e110949..7acb56c 100644 +--- a/block/ioctl.c ++++ b/block/ioctl.c +@@ -5,6 +5,7 @@ + #include + #include + #include ++#include + #include + + static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) +@@ -189,6 +190,11 @@ static int blkdev_locked_ioctl(struct fi + return put_ulong(arg, bdev->bd_inode->i_size >> 9); + case BLKGETSIZE64: + return put_u64(arg, bdev->bd_inode->i_size); ++ case BLKTRACESTART: ++ case BLKTRACESTOP: ++ case BLKTRACESETUP: ++ case BLKTRACETEARDOWN: ++ return blk_trace_ioctl(bdev, cmd, (char __user *) arg); + } + return -ENOIOCTLCMD; + } +diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c +index 03d9c82..41387f5 100644 +--- a/block/ll_rw_blk.c ++++ b/block/ll_rw_blk.c +@@ -28,6 +28,7 @@ + #include + #include + #include ++#include + + /* + * for max sense size +@@ -1551,8 +1552,10 @@ void blk_plug_device(request_queue_t *q) + if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)) + return; + +- if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) ++ if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { + mod_timer(&q->unplug_timer, jiffies + q->unplug_delay); ++ blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG); ++ } + } + + EXPORT_SYMBOL(blk_plug_device); +@@ -1616,14 +1619,21 @@ static void blk_backing_dev_unplug(struc + /* + * devices don't necessarily have an ->unplug_fn defined + */ +- if (q->unplug_fn) ++ if (q->unplug_fn) { ++ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL, ++ q->rq.count[READ] + q->rq.count[WRITE]); ++ + q->unplug_fn(q); ++ } + } + + static void blk_unplug_work(void *data) + { + request_queue_t *q = data; + ++ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL, ++ q->rq.count[READ] + q->rq.count[WRITE]); ++ + q->unplug_fn(q); + } + +@@ -1631,6 +1641,9 @@ static void blk_unplug_timeout(unsigned + { + request_queue_t *q = (request_queue_t *)data; + ++ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_TIMER, NULL, ++ q->rq.count[READ] + q->rq.count[WRITE]); ++ + kblockd_schedule_work(&q->unplug_work); + } + +@@ -1753,6 +1766,9 @@ void blk_cleanup_queue(request_queue_t * + if (q->queue_tags) + __blk_queue_free_tags(q); + ++ if (q->blk_trace) ++ blk_trace_shutdown(q); ++ + kmem_cache_free(requestq_cachep, q); + } + +@@ -2104,6 +2120,8 @@ rq_starved: + + rq_init(q, rq); + rq->rl = rl; ++ ++ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ); + out: + return rq; + } +@@ -2132,6 +2150,8 @@ static struct request *get_request_wait( + if (!rq) { + struct io_context *ioc; + ++ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ); ++ + __generic_unplug_device(q); + spin_unlock_irq(q->queue_lock); + io_schedule(); +@@ -2185,6 +2205,8 @@ EXPORT_SYMBOL(blk_get_request); + */ + void blk_requeue_request(request_queue_t *q, struct request *rq) + { ++ blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); ++ + if (blk_rq_tagged(rq)) + blk_queue_end_tag(q, rq); + +@@ -2819,6 +2841,8 @@ static int __make_request(request_queue_ + if (!q->back_merge_fn(q, req, bio)) + break; + ++ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); ++ + req->biotail->bi_next = bio; + req->biotail = bio; + req->nr_sectors = req->hard_nr_sectors += nr_sectors; +@@ -2834,6 +2858,8 @@ static int __make_request(request_queue_ + if (!q->front_merge_fn(q, req, bio)) + break; + ++ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); ++ + bio->bi_next = req->bio; + req->bio = bio; + +@@ -2951,6 +2977,7 @@ void generic_make_request(struct bio *bi + request_queue_t *q; + sector_t maxsector; + int ret, nr_sectors = bio_sectors(bio); ++ dev_t old_dev; + + might_sleep(); + /* Test device or partition size, when known. */ +@@ -2977,6 +3004,8 @@ void generic_make_request(struct bio *bi + * NOTE: we don't repeat the blk_size check for each new device. + * Stacking drivers are expected to know what they are doing. + */ ++ maxsector = -1; ++ old_dev = 0; + do { + char b[BDEVNAME_SIZE]; + +@@ -3009,6 +3038,15 @@ end_io: + */ + blk_partition_remap(bio); + ++ if (maxsector != -1) ++ blk_add_trace_remap(q, bio, old_dev, bio->bi_sector, ++ maxsector); ++ ++ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); ++ ++ maxsector = bio->bi_sector; ++ old_dev = bio->bi_bdev->bd_dev; ++ + ret = q->make_request_fn(q, bio); + } while (ret); + } +@@ -3128,6 +3166,8 @@ static int __end_that_request_first(stru + int total_bytes, bio_nbytes, error, next_idx = 0; + struct bio *bio; + ++ blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE); ++ + /* + * extend uptodate bool to allow < 0 value to be direct io error + */ +diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c +index 0d65394..234048e 100644 +--- a/drivers/block/cciss.c ++++ b/drivers/block/cciss.c +@@ -38,6 +38,7 @@ + #include + #include + #include ++#include + #include + #include + +@@ -2331,6 +2332,7 @@ static inline void complete_command( ctl + + cmd->rq->completion_data = cmd; + cmd->rq->errors = status; ++ blk_add_trace_rq(cmd->rq->q, cmd->rq, BLK_TA_COMPLETE); + blk_complete_request(cmd->rq); + } + +diff --git a/drivers/md/dm.c b/drivers/md/dm.c +index 745ca1f..f36613e 100644 +--- a/drivers/md/dm.c ++++ b/drivers/md/dm.c +@@ -17,6 +17,7 @@ + #include + #include + #include ++#include + + static const char *_name = DM_NAME; + +@@ -334,6 +335,8 @@ static void dec_pending(struct dm_io *io + /* nudge anyone waiting on suspend queue */ + wake_up(&io->md->wait); + ++ blk_add_trace_bio(io->md->queue, io->bio, BLK_TA_COMPLETE); ++ + bio_endio(io->bio, io->bio->bi_size, io->error); + free_io(io->md, io); + } +@@ -392,6 +395,7 @@ static void __map_bio(struct dm_target * + struct target_io *tio) + { + int r; ++ sector_t sector; + + /* + * Sanity checks. +@@ -407,10 +411,17 @@ static void __map_bio(struct dm_target * + * this io. + */ + atomic_inc(&tio->io->io_count); ++ sector = clone->bi_sector; + r = ti->type->map(ti, clone, &tio->info); +- if (r > 0) ++ if (r > 0) { + /* the bio has been remapped so dispatch it */ ++ ++ blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, ++ tio->io->bio->bi_bdev->bd_dev, sector, ++ clone->bi_sector); ++ + generic_make_request(clone); ++ } + + else if (r < 0) { + /* error the io and bail out */ +diff --git a/fs/Kconfig b/fs/Kconfig +index e9749b0..c8d0a20 100644 +--- a/fs/Kconfig ++++ b/fs/Kconfig +@@ -859,18 +859,6 @@ config RAMFS + To compile this as a module, choose M here: the module will be called + ramfs. + +-config RELAYFS_FS +- tristate "Relayfs file system support" +- ---help--- +- Relayfs is a high-speed data relay filesystem designed to provide +- an efficient mechanism for tools and facilities to relay large +- amounts of data from kernel space to user space. +- +- To compile this code as a module, choose M here: the module will be +- called relayfs. +- +- If unsure, say N. +- + config CONFIGFS_FS + tristate "Userspace-driven configuration filesystem (EXPERIMENTAL)" + depends on EXPERIMENTAL +diff --git a/fs/Makefile b/fs/Makefile +index 1db7113..080b386 100644 +--- a/fs/Makefile ++++ b/fs/Makefile +@@ -91,7 +91,6 @@ obj-$(CONFIG_AUTOFS4_FS) += autofs4/ + obj-$(CONFIG_ADFS_FS) += adfs/ + obj-$(CONFIG_FUSE_FS) += fuse/ + obj-$(CONFIG_UDF_FS) += udf/ +-obj-$(CONFIG_RELAYFS_FS) += relayfs/ + obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/ + obj-$(CONFIG_JFS_FS) += jfs/ + obj-$(CONFIG_XFS_FS) += xfs/ +diff --git a/fs/bio.c b/fs/bio.c +index 1f3bb50..0dd0d81 100644 +--- a/fs/bio.c ++++ b/fs/bio.c +@@ -25,6 +25,7 @@ + #include + #include + #include ++#include + #include /* for struct sg_iovec */ + + #define BIO_POOL_SIZE 256 +@@ -1095,6 +1096,9 @@ struct bio_pair *bio_split(struct bio *b + if (!bp) + return bp; + ++ blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi, ++ bi->bi_sector + first_sectors); ++ + BUG_ON(bi->bi_vcnt != 1); + BUG_ON(bi->bi_idx != 0); + atomic_set(&bp->cnt, 3); +diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c +index 537ac70..48318d9 100644 +--- a/fs/compat_ioctl.c ++++ b/fs/compat_ioctl.c +@@ -72,6 +72,7 @@ + #include + #include + #include ++#include + + #include /* siocdevprivate_ioctl */ + #include +diff --git a/fs/relayfs/Makefile b/fs/relayfs/Makefile +deleted file mode 100644 +index e76e182..0000000 +--- a/fs/relayfs/Makefile ++++ /dev/null +@@ -1,4 +0,0 @@ +-obj-$(CONFIG_RELAYFS_FS) += relayfs.o +- +-relayfs-y := relay.o inode.o buffers.o +- +diff --git a/fs/relayfs/buffers.c b/fs/relayfs/buffers.c +deleted file mode 100644 +index 1018781..0000000 +--- a/fs/relayfs/buffers.c ++++ /dev/null +@@ -1,190 +0,0 @@ +-/* +- * RelayFS buffer management code. +- * +- * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp +- * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) +- * +- * This file is released under the GPL. +- */ +- +-#include +-#include +-#include +-#include +-#include "relay.h" +-#include "buffers.h" +- +-/* +- * close() vm_op implementation for relayfs file mapping. +- */ +-static void relay_file_mmap_close(struct vm_area_struct *vma) +-{ +- struct rchan_buf *buf = vma->vm_private_data; +- buf->chan->cb->buf_unmapped(buf, vma->vm_file); +-} +- +-/* +- * nopage() vm_op implementation for relayfs file mapping. +- */ +-static struct page *relay_buf_nopage(struct vm_area_struct *vma, +- unsigned long address, +- int *type) +-{ +- struct page *page; +- struct rchan_buf *buf = vma->vm_private_data; +- unsigned long offset = address - vma->vm_start; +- +- if (address > vma->vm_end) +- return NOPAGE_SIGBUS; /* Disallow mremap */ +- if (!buf) +- return NOPAGE_OOM; +- +- page = vmalloc_to_page(buf->start + offset); +- if (!page) +- return NOPAGE_OOM; +- get_page(page); +- +- if (type) +- *type = VM_FAULT_MINOR; +- +- return page; +-} +- +-/* +- * vm_ops for relay file mappings. +- */ +-static struct vm_operations_struct relay_file_mmap_ops = { +- .nopage = relay_buf_nopage, +- .close = relay_file_mmap_close, +-}; +- +-/** +- * relay_mmap_buf: - mmap channel buffer to process address space +- * @buf: relay channel buffer +- * @vma: vm_area_struct describing memory to be mapped +- * +- * Returns 0 if ok, negative on error +- * +- * Caller should already have grabbed mmap_sem. +- */ +-int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) +-{ +- unsigned long length = vma->vm_end - vma->vm_start; +- struct file *filp = vma->vm_file; +- +- if (!buf) +- return -EBADF; +- +- if (length != (unsigned long)buf->chan->alloc_size) +- return -EINVAL; +- +- vma->vm_ops = &relay_file_mmap_ops; +- vma->vm_private_data = buf; +- buf->chan->cb->buf_mapped(buf, filp); +- +- return 0; +-} +- +-/** +- * relay_alloc_buf - allocate a channel buffer +- * @buf: the buffer struct +- * @size: total size of the buffer +- * +- * Returns a pointer to the resulting buffer, NULL if unsuccessful +- */ +-static void *relay_alloc_buf(struct rchan_buf *buf, unsigned long size) +-{ +- void *mem; +- unsigned int i, j, n_pages; +- +- size = PAGE_ALIGN(size); +- n_pages = size >> PAGE_SHIFT; +- +- buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); +- if (!buf->page_array) +- return NULL; +- +- for (i = 0; i < n_pages; i++) { +- buf->page_array[i] = alloc_page(GFP_KERNEL); +- if (unlikely(!buf->page_array[i])) +- goto depopulate; +- } +- mem = vmap(buf->page_array, n_pages, VM_MAP, PAGE_KERNEL); +- if (!mem) +- goto depopulate; +- +- memset(mem, 0, size); +- buf->page_count = n_pages; +- return mem; +- +-depopulate: +- for (j = 0; j < i; j++) +- __free_page(buf->page_array[j]); +- kfree(buf->page_array); +- return NULL; +-} +- +-/** +- * relay_create_buf - allocate and initialize a channel buffer +- * @alloc_size: size of the buffer to allocate +- * @n_subbufs: number of sub-buffers in the channel +- * +- * Returns channel buffer if successful, NULL otherwise +- */ +-struct rchan_buf *relay_create_buf(struct rchan *chan) +-{ +- struct rchan_buf *buf = kcalloc(1, sizeof(struct rchan_buf), GFP_KERNEL); +- if (!buf) +- return NULL; +- +- buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL); +- if (!buf->padding) +- goto free_buf; +- +- buf->start = relay_alloc_buf(buf, chan->alloc_size); +- if (!buf->start) +- goto free_buf; +- +- buf->chan = chan; +- kref_get(&buf->chan->kref); +- return buf; +- +-free_buf: +- kfree(buf->padding); +- kfree(buf); +- return NULL; +-} +- +-/** +- * relay_destroy_buf - destroy an rchan_buf struct and associated buffer +- * @buf: the buffer struct +- */ +-void relay_destroy_buf(struct rchan_buf *buf) +-{ +- struct rchan *chan = buf->chan; +- unsigned int i; +- +- if (likely(buf->start)) { +- vunmap(buf->start); +- for (i = 0; i < buf->page_count; i++) +- __free_page(buf->page_array[i]); +- kfree(buf->page_array); +- } +- kfree(buf->padding); +- kfree(buf); +- kref_put(&chan->kref, relay_destroy_channel); +-} +- +-/** +- * relay_remove_buf - remove a channel buffer +- * +- * Removes the file from the relayfs fileystem, which also frees the +- * rchan_buf_struct and the channel buffer. Should only be called from +- * kref_put(). +- */ +-void relay_remove_buf(struct kref *kref) +-{ +- struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref); +- buf->chan->cb->remove_buf_file(buf->dentry); +- relay_destroy_buf(buf); +-} +diff --git a/fs/relayfs/buffers.h b/fs/relayfs/buffers.h +deleted file mode 100644 +index 37a1249..0000000 +--- a/fs/relayfs/buffers.h ++++ /dev/null +@@ -1,12 +0,0 @@ +-#ifndef _BUFFERS_H +-#define _BUFFERS_H +- +-/* This inspired by rtai/shmem */ +-#define FIX_SIZE(x) (((x) - 1) & PAGE_MASK) + PAGE_SIZE +- +-extern int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma); +-extern struct rchan_buf *relay_create_buf(struct rchan *chan); +-extern void relay_destroy_buf(struct rchan_buf *buf); +-extern void relay_remove_buf(struct kref *kref); +- +-#endif/* _BUFFERS_H */ +diff --git a/fs/relayfs/inode.c b/fs/relayfs/inode.c +deleted file mode 100644 +index 3835230..0000000 +--- a/fs/relayfs/inode.c ++++ /dev/null +@@ -1,581 +0,0 @@ +-/* +- * VFS-related code for RelayFS, a high-speed data relay filesystem. +- * +- * Copyright (C) 2003-2005 - Tom Zanussi , IBM Corp +- * Copyright (C) 2003-2005 - Karim Yaghmour +- * +- * Based on ramfs, Copyright (C) 2002 - Linus Torvalds +- * +- * This file is released under the GPL. +- */ +- +-#include +-#include +-#include +-#include +-#include +-#include +-#include +-#include +-#include +-#include +-#include "relay.h" +-#include "buffers.h" +- +-#define RELAYFS_MAGIC 0xF0B4A981 +- +-static struct vfsmount * relayfs_mount; +-static int relayfs_mount_count; +- +-static struct backing_dev_info relayfs_backing_dev_info = { +- .ra_pages = 0, /* No readahead */ +- .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK, +-}; +- +-static struct inode *relayfs_get_inode(struct super_block *sb, +- int mode, +- struct file_operations *fops, +- void *data) +-{ +- struct inode *inode; +- +- inode = new_inode(sb); +- if (!inode) +- return NULL; +- +- inode->i_mode = mode; +- inode->i_uid = 0; +- inode->i_gid = 0; +- inode->i_blksize = PAGE_CACHE_SIZE; +- inode->i_blocks = 0; +- inode->i_mapping->backing_dev_info = &relayfs_backing_dev_info; +- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; +- switch (mode & S_IFMT) { +- case S_IFREG: +- inode->i_fop = fops; +- if (data) +- inode->u.generic_ip = data; +- break; +- case S_IFDIR: +- inode->i_op = &simple_dir_inode_operations; +- inode->i_fop = &simple_dir_operations; +- +- /* directory inodes start off with i_nlink == 2 (for "." entry) */ +- inode->i_nlink++; +- break; +- default: +- break; +- } +- +- return inode; +-} +- +-/** +- * relayfs_create_entry - create a relayfs directory or file +- * @name: the name of the file to create +- * @parent: parent directory +- * @mode: mode +- * @fops: file operations to use for the file +- * @data: user-associated data for this file +- * +- * Returns the new dentry, NULL on failure +- * +- * Creates a file or directory with the specifed permissions. +- */ +-static struct dentry *relayfs_create_entry(const char *name, +- struct dentry *parent, +- int mode, +- struct file_operations *fops, +- void *data) +-{ +- struct dentry *d; +- struct inode *inode; +- int error = 0; +- +- BUG_ON(!name || !(S_ISREG(mode) || S_ISDIR(mode))); +- +- error = simple_pin_fs("relayfs", &relayfs_mount, &relayfs_mount_count); +- if (error) { +- printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", error); +- return NULL; +- } +- +- if (!parent && relayfs_mount && relayfs_mount->mnt_sb) +- parent = relayfs_mount->mnt_sb->s_root; +- +- if (!parent) { +- simple_release_fs(&relayfs_mount, &relayfs_mount_count); +- return NULL; +- } +- +- parent = dget(parent); +- mutex_lock(&parent->d_inode->i_mutex); +- d = lookup_one_len(name, parent, strlen(name)); +- if (IS_ERR(d)) { +- d = NULL; +- goto release_mount; +- } +- +- if (d->d_inode) { +- d = NULL; +- goto release_mount; +- } +- +- inode = relayfs_get_inode(parent->d_inode->i_sb, mode, fops, data); +- if (!inode) { +- d = NULL; +- goto release_mount; +- } +- +- d_instantiate(d, inode); +- dget(d); /* Extra count - pin the dentry in core */ +- +- if (S_ISDIR(mode)) +- parent->d_inode->i_nlink++; +- +- goto exit; +- +-release_mount: +- simple_release_fs(&relayfs_mount, &relayfs_mount_count); +- +-exit: +- mutex_unlock(&parent->d_inode->i_mutex); +- dput(parent); +- return d; +-} +- +-/** +- * relayfs_create_file - create a file in the relay filesystem +- * @name: the name of the file to create +- * @parent: parent directory +- * @mode: mode, if not specied the default perms are used +- * @fops: file operations to use for the file +- * @data: user-associated data for this file +- * +- * Returns file dentry if successful, NULL otherwise. +- * +- * The file will be created user r on behalf of current user. +- */ +-struct dentry *relayfs_create_file(const char *name, +- struct dentry *parent, +- int mode, +- struct file_operations *fops, +- void *data) +-{ +- BUG_ON(!fops); +- +- if (!mode) +- mode = S_IRUSR; +- mode = (mode & S_IALLUGO) | S_IFREG; +- +- return relayfs_create_entry(name, parent, mode, fops, data); +-} +- +-/** +- * relayfs_create_dir - create a directory in the relay filesystem +- * @name: the name of the directory to create +- * @parent: parent directory, NULL if parent should be fs root +- * +- * Returns directory dentry if successful, NULL otherwise. +- * +- * The directory will be created world rwx on behalf of current user. +- */ +-struct dentry *relayfs_create_dir(const char *name, struct dentry *parent) +-{ +- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; +- return relayfs_create_entry(name, parent, mode, NULL, NULL); +-} +- +-/** +- * relayfs_remove - remove a file or directory in the relay filesystem +- * @dentry: file or directory dentry +- * +- * Returns 0 if successful, negative otherwise. +- */ +-int relayfs_remove(struct dentry *dentry) +-{ +- struct dentry *parent; +- int error = 0; +- +- if (!dentry) +- return -EINVAL; +- parent = dentry->d_parent; +- if (!parent) +- return -EINVAL; +- +- parent = dget(parent); +- mutex_lock(&parent->d_inode->i_mutex); +- if (dentry->d_inode) { +- if (S_ISDIR(dentry->d_inode->i_mode)) +- error = simple_rmdir(parent->d_inode, dentry); +- else +- error = simple_unlink(parent->d_inode, dentry); +- if (!error) +- d_delete(dentry); +- } +- if (!error) +- dput(dentry); +- mutex_unlock(&parent->d_inode->i_mutex); +- dput(parent); +- +- if (!error) +- simple_release_fs(&relayfs_mount, &relayfs_mount_count); +- +- return error; +-} +- +-/** +- * relayfs_remove_file - remove a file from relay filesystem +- * @dentry: directory dentry +- * +- * Returns 0 if successful, negative otherwise. +- */ +-int relayfs_remove_file(struct dentry *dentry) +-{ +- return relayfs_remove(dentry); +-} +- +-/** +- * relayfs_remove_dir - remove a directory in the relay filesystem +- * @dentry: directory dentry +- * +- * Returns 0 if successful, negative otherwise. +- */ +-int relayfs_remove_dir(struct dentry *dentry) +-{ +- return relayfs_remove(dentry); +-} +- +-/** +- * relay_file_open - open file op for relay files +- * @inode: the inode +- * @filp: the file +- * +- * Increments the channel buffer refcount. +- */ +-static int relay_file_open(struct inode *inode, struct file *filp) +-{ +- struct rchan_buf *buf = inode->u.generic_ip; +- kref_get(&buf->kref); +- filp->private_data = buf; +- +- return 0; +-} +- +-/** +- * relay_file_mmap - mmap file op for relay files +- * @filp: the file +- * @vma: the vma describing what to map +- * +- * Calls upon relay_mmap_buf to map the file into user space. +- */ +-static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) +-{ +- struct rchan_buf *buf = filp->private_data; +- return relay_mmap_buf(buf, vma); +-} +- +-/** +- * relay_file_poll - poll file op for relay files +- * @filp: the file +- * @wait: poll table +- * +- * Poll implemention. +- */ +-static unsigned int relay_file_poll(struct file *filp, poll_table *wait) +-{ +- unsigned int mask = 0; +- struct rchan_buf *buf = filp->private_data; +- +- if (buf->finalized) +- return POLLERR; +- +- if (filp->f_mode & FMODE_READ) { +- poll_wait(filp, &buf->read_wait, wait); +- if (!relay_buf_empty(buf)) +- mask |= POLLIN | POLLRDNORM; +- } +- +- return mask; +-} +- +-/** +- * relay_file_release - release file op for relay files +- * @inode: the inode +- * @filp: the file +- * +- * Decrements the channel refcount, as the filesystem is +- * no longer using it. +- */ +-static int relay_file_release(struct inode *inode, struct file *filp) +-{ +- struct rchan_buf *buf = filp->private_data; +- kref_put(&buf->kref, relay_remove_buf); +- +- return 0; +-} +- +-/** +- * relay_file_read_consume - update the consumed count for the buffer +- */ +-static void relay_file_read_consume(struct rchan_buf *buf, +- size_t read_pos, +- size_t bytes_consumed) +-{ +- size_t subbuf_size = buf->chan->subbuf_size; +- size_t n_subbufs = buf->chan->n_subbufs; +- size_t read_subbuf; +- +- if (buf->bytes_consumed + bytes_consumed > subbuf_size) { +- relay_subbufs_consumed(buf->chan, buf->cpu, 1); +- buf->bytes_consumed = 0; +- } +- +- buf->bytes_consumed += bytes_consumed; +- read_subbuf = read_pos / buf->chan->subbuf_size; +- if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) { +- if ((read_subbuf == buf->subbufs_produced % n_subbufs) && +- (buf->offset == subbuf_size)) +- return; +- relay_subbufs_consumed(buf->chan, buf->cpu, 1); +- buf->bytes_consumed = 0; +- } +-} +- +-/** +- * relay_file_read_avail - boolean, are there unconsumed bytes available? +- */ +-static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos) +-{ +- size_t bytes_produced, bytes_consumed, write_offset; +- size_t subbuf_size = buf->chan->subbuf_size; +- size_t n_subbufs = buf->chan->n_subbufs; +- size_t produced = buf->subbufs_produced % n_subbufs; +- size_t consumed = buf->subbufs_consumed % n_subbufs; +- +- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; +- +- if (consumed > produced) { +- if ((produced > n_subbufs) && +- (produced + n_subbufs - consumed <= n_subbufs)) +- produced += n_subbufs; +- } else if (consumed == produced) { +- if (buf->offset > subbuf_size) { +- produced += n_subbufs; +- if (buf->subbufs_produced == buf->subbufs_consumed) +- consumed += n_subbufs; +- } +- } +- +- if (buf->offset > subbuf_size) +- bytes_produced = (produced - 1) * subbuf_size + write_offset; +- else +- bytes_produced = produced * subbuf_size + write_offset; +- bytes_consumed = consumed * subbuf_size + buf->bytes_consumed; +- +- if (bytes_produced == bytes_consumed) +- return 0; +- +- relay_file_read_consume(buf, read_pos, 0); +- +- return 1; +-} +- +-/** +- * relay_file_read_subbuf_avail - return bytes available in sub-buffer +- */ +-static size_t relay_file_read_subbuf_avail(size_t read_pos, +- struct rchan_buf *buf) +-{ +- size_t padding, avail = 0; +- size_t read_subbuf, read_offset, write_subbuf, write_offset; +- size_t subbuf_size = buf->chan->subbuf_size; +- +- write_subbuf = (buf->data - buf->start) / subbuf_size; +- write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; +- read_subbuf = read_pos / subbuf_size; +- read_offset = read_pos % subbuf_size; +- padding = buf->padding[read_subbuf]; +- +- if (read_subbuf == write_subbuf) { +- if (read_offset + padding < write_offset) +- avail = write_offset - (read_offset + padding); +- } else +- avail = (subbuf_size - padding) - read_offset; +- +- return avail; +-} +- +-/** +- * relay_file_read_start_pos - find the first available byte to read +- * +- * If the read_pos is in the middle of padding, return the +- * position of the first actually available byte, otherwise +- * return the original value. +- */ +-static size_t relay_file_read_start_pos(size_t read_pos, +- struct rchan_buf *buf) +-{ +- size_t read_subbuf, padding, padding_start, padding_end; +- size_t subbuf_size = buf->chan->subbuf_size; +- size_t n_subbufs = buf->chan->n_subbufs; +- +- read_subbuf = read_pos / subbuf_size; +- padding = buf->padding[read_subbuf]; +- padding_start = (read_subbuf + 1) * subbuf_size - padding; +- padding_end = (read_subbuf + 1) * subbuf_size; +- if (read_pos >= padding_start && read_pos < padding_end) { +- read_subbuf = (read_subbuf + 1) % n_subbufs; +- read_pos = read_subbuf * subbuf_size; +- } +- +- return read_pos; +-} +- +-/** +- * relay_file_read_end_pos - return the new read position +- */ +-static size_t relay_file_read_end_pos(struct rchan_buf *buf, +- size_t read_pos, +- size_t count) +-{ +- size_t read_subbuf, padding, end_pos; +- size_t subbuf_size = buf->chan->subbuf_size; +- size_t n_subbufs = buf->chan->n_subbufs; +- +- read_subbuf = read_pos / subbuf_size; +- padding = buf->padding[read_subbuf]; +- if (read_pos % subbuf_size + count + padding == subbuf_size) +- end_pos = (read_subbuf + 1) * subbuf_size; +- else +- end_pos = read_pos + count; +- if (end_pos >= subbuf_size * n_subbufs) +- end_pos = 0; +- +- return end_pos; +-} +- +-/** +- * relay_file_read - read file op for relay files +- * @filp: the file +- * @buffer: the userspace buffer +- * @count: number of bytes to read +- * @ppos: position to read from +- * +- * Reads count bytes or the number of bytes available in the +- * current sub-buffer being read, whichever is smaller. +- */ +-static ssize_t relay_file_read(struct file *filp, +- char __user *buffer, +- size_t count, +- loff_t *ppos) +-{ +- struct rchan_buf *buf = filp->private_data; +- struct inode *inode = filp->f_dentry->d_inode; +- size_t read_start, avail; +- ssize_t ret = 0; +- void *from; +- +- mutex_lock(&inode->i_mutex); +- if(!relay_file_read_avail(buf, *ppos)) +- goto out; +- +- read_start = relay_file_read_start_pos(*ppos, buf); +- avail = relay_file_read_subbuf_avail(read_start, buf); +- if (!avail) +- goto out; +- +- from = buf->start + read_start; +- ret = count = min(count, avail); +- if (copy_to_user(buffer, from, count)) { +- ret = -EFAULT; +- goto out; +- } +- relay_file_read_consume(buf, read_start, count); +- *ppos = relay_file_read_end_pos(buf, read_start, count); +-out: +- mutex_unlock(&inode->i_mutex); +- return ret; +-} +- +-struct file_operations relay_file_operations = { +- .open = relay_file_open, +- .poll = relay_file_poll, +- .mmap = relay_file_mmap, +- .read = relay_file_read, +- .llseek = no_llseek, +- .release = relay_file_release, +-}; +- +-static struct super_operations relayfs_ops = { +- .statfs = simple_statfs, +- .drop_inode = generic_delete_inode, +-}; +- +-static int relayfs_fill_super(struct super_block * sb, void * data, int silent) +-{ +- struct inode *inode; +- struct dentry *root; +- int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; +- +- sb->s_blocksize = PAGE_CACHE_SIZE; +- sb->s_blocksize_bits = PAGE_CACHE_SHIFT; +- sb->s_magic = RELAYFS_MAGIC; +- sb->s_op = &relayfs_ops; +- inode = relayfs_get_inode(sb, mode, NULL, NULL); +- +- if (!inode) +- return -ENOMEM; +- +- root = d_alloc_root(inode); +- if (!root) { +- iput(inode); +- return -ENOMEM; +- } +- sb->s_root = root; +- +- return 0; +-} +- +-static struct super_block * relayfs_get_sb(struct file_system_type *fs_type, +- int flags, const char *dev_name, +- void *data) +-{ +- return get_sb_single(fs_type, flags, data, relayfs_fill_super); +-} +- +-static struct file_system_type relayfs_fs_type = { +- .owner = THIS_MODULE, +- .name = "relayfs", +- .get_sb = relayfs_get_sb, +- .kill_sb = kill_litter_super, +-}; +- +-static int __init init_relayfs_fs(void) +-{ +- return register_filesystem(&relayfs_fs_type); +-} +- +-static void __exit exit_relayfs_fs(void) +-{ +- +- +- +- +- +- unregister_filesystem(&relayfs_fs_type); +-} +- +-module_init(init_relayfs_fs) +-module_exit(exit_relayfs_fs) +- +-EXPORT_SYMBOL_GPL(relay_file_operations); +-EXPORT_SYMBOL_GPL(relayfs_create_dir); +-EXPORT_SYMBOL_GPL(relayfs_remove_dir); +-EXPORT_SYMBOL_GPL(relayfs_create_file); +-EXPORT_SYMBOL_GPL(relayfs_remove_file); +- +-MODULE_AUTHOR("Tom Zanussi and Karim Yaghmour "); +-MODULE_DESCRIPTION("Relay Filesystem"); +-MODULE_LICENSE("GPL"); +- +diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c +deleted file mode 100644 +index abf3cea..0000000 +--- a/fs/relayfs/relay.c ++++ /dev/null +@@ -1,482 +0,0 @@ +-/* +- * Public API and common code for RelayFS. +- * +- * See Documentation/filesystems/relayfs.txt for an overview of relayfs. +- * +- * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp +- * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) +- * +- * This file is released under the GPL. +- */ +- +-#include +-#include +-#include +-#include +-#include +-#include +-#include "relay.h" +-#include "buffers.h" +- +-/** +- * relay_buf_empty - boolean, is the channel buffer empty? +- * @buf: channel buffer +- * +- * Returns 1 if the buffer is empty, 0 otherwise. +- */ +-int relay_buf_empty(struct rchan_buf *buf) +-{ +- return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1; +-} +- +-/** +- * relay_buf_full - boolean, is the channel buffer full? +- * @buf: channel buffer +- * +- * Returns 1 if the buffer is full, 0 otherwise. +- */ +-int relay_buf_full(struct rchan_buf *buf) +-{ +- size_t ready = buf->subbufs_produced - buf->subbufs_consumed; +- return (ready >= buf->chan->n_subbufs) ? 1 : 0; +-} +- +-/* +- * High-level relayfs kernel API and associated functions. +- */ +- +-/* +- * rchan_callback implementations defining default channel behavior. Used +- * in place of corresponding NULL values in client callback struct. +- */ +- +-/* +- * subbuf_start() default callback. Does nothing. +- */ +-static int subbuf_start_default_callback (struct rchan_buf *buf, +- void *subbuf, +- void *prev_subbuf, +- size_t prev_padding) +-{ +- if (relay_buf_full(buf)) +- return 0; +- +- return 1; +-} +- +-/* +- * buf_mapped() default callback. Does nothing. +- */ +-static void buf_mapped_default_callback(struct rchan_buf *buf, +- struct file *filp) +-{ +-} +- +-/* +- * buf_unmapped() default callback. Does nothing. +- */ +-static void buf_unmapped_default_callback(struct rchan_buf *buf, +- struct file *filp) +-{ +-} +- +-/* +- * create_buf_file_create() default callback. Creates file to represent buf. +- */ +-static struct dentry *create_buf_file_default_callback(const char *filename, +- struct dentry *parent, +- int mode, +- struct rchan_buf *buf, +- int *is_global) +-{ +- return relayfs_create_file(filename, parent, mode, +- &relay_file_operations, buf); +-} +- +-/* +- * remove_buf_file() default callback. Removes file representing relay buffer. +- */ +-static int remove_buf_file_default_callback(struct dentry *dentry) +-{ +- return relayfs_remove(dentry); +-} +- +-/* relay channel default callbacks */ +-static struct rchan_callbacks default_channel_callbacks = { +- .subbuf_start = subbuf_start_default_callback, +- .buf_mapped = buf_mapped_default_callback, +- .buf_unmapped = buf_unmapped_default_callback, +- .create_buf_file = create_buf_file_default_callback, +- .remove_buf_file = remove_buf_file_default_callback, +-}; +- +-/** +- * wakeup_readers - wake up readers waiting on a channel +- * @private: the channel buffer +- * +- * This is the work function used to defer reader waking. The +- * reason waking is deferred is that calling directly from write +- * causes problems if you're writing from say the scheduler. +- */ +-static void wakeup_readers(void *private) +-{ +- struct rchan_buf *buf = private; +- wake_up_interruptible(&buf->read_wait); +-} +- +-/** +- * __relay_reset - reset a channel buffer +- * @buf: the channel buffer +- * @init: 1 if this is a first-time initialization +- * +- * See relay_reset for description of effect. +- */ +-static inline void __relay_reset(struct rchan_buf *buf, unsigned int init) +-{ +- size_t i; +- +- if (init) { +- init_waitqueue_head(&buf->read_wait); +- kref_init(&buf->kref); +- INIT_WORK(&buf->wake_readers, NULL, NULL); +- } else { +- cancel_delayed_work(&buf->wake_readers); +- flush_scheduled_work(); +- } +- +- buf->subbufs_produced = 0; +- buf->subbufs_consumed = 0; +- buf->bytes_consumed = 0; +- buf->finalized = 0; +- buf->data = buf->start; +- buf->offset = 0; +- +- for (i = 0; i < buf->chan->n_subbufs; i++) +- buf->padding[i] = 0; +- +- buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0); +-} +- +-/** +- * relay_reset - reset the channel +- * @chan: the channel +- * +- * This has the effect of erasing all data from all channel buffers +- * and restarting the channel in its initial state. The buffers +- * are not freed, so any mappings are still in effect. +- * +- * NOTE: Care should be taken that the channel isn't actually +- * being used by anything when this call is made. +- */ +-void relay_reset(struct rchan *chan) +-{ +- unsigned int i; +- struct rchan_buf *prev = NULL; +- +- if (!chan) +- return; +- +- for (i = 0; i < NR_CPUS; i++) { +- if (!chan->buf[i] || chan->buf[i] == prev) +- break; +- __relay_reset(chan->buf[i], 0); +- prev = chan->buf[i]; +- } +-} +- +-/** +- * relay_open_buf - create a new channel buffer in relayfs +- * +- * Internal - used by relay_open(). +- */ +-static struct rchan_buf *relay_open_buf(struct rchan *chan, +- const char *filename, +- struct dentry *parent, +- int *is_global) +-{ +- struct rchan_buf *buf; +- struct dentry *dentry; +- +- if (*is_global) +- return chan->buf[0]; +- +- buf = relay_create_buf(chan); +- if (!buf) +- return NULL; +- +- /* Create file in fs */ +- dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR, +- buf, is_global); +- if (!dentry) { +- relay_destroy_buf(buf); +- return NULL; +- } +- +- buf->dentry = dentry; +- __relay_reset(buf, 1); +- +- return buf; +-} +- +-/** +- * relay_close_buf - close a channel buffer +- * @buf: channel buffer +- * +- * Marks the buffer finalized and restores the default callbacks. +- * The channel buffer and channel buffer data structure are then freed +- * automatically when the last reference is given up. +- */ +-static inline void relay_close_buf(struct rchan_buf *buf) +-{ +- buf->finalized = 1; +- buf->chan->cb = &default_channel_callbacks; +- cancel_delayed_work(&buf->wake_readers); +- flush_scheduled_work(); +- kref_put(&buf->kref, relay_remove_buf); +-} +- +-static inline void setup_callbacks(struct rchan *chan, +- struct rchan_callbacks *cb) +-{ +- if (!cb) { +- chan->cb = &default_channel_callbacks; +- return; +- } +- +- if (!cb->subbuf_start) +- cb->subbuf_start = subbuf_start_default_callback; +- if (!cb->buf_mapped) +- cb->buf_mapped = buf_mapped_default_callback; +- if (!cb->buf_unmapped) +- cb->buf_unmapped = buf_unmapped_default_callback; +- if (!cb->create_buf_file) +- cb->create_buf_file = create_buf_file_default_callback; +- if (!cb->remove_buf_file) +- cb->remove_buf_file = remove_buf_file_default_callback; +- chan->cb = cb; +-} +- +-/** +- * relay_open - create a new relayfs channel +- * @base_filename: base name of files to create +- * @parent: dentry of parent directory, NULL for root directory +- * @subbuf_size: size of sub-buffers +- * @n_subbufs: number of sub-buffers +- * @cb: client callback functions +- * +- * Returns channel pointer if successful, NULL otherwise. +- * +- * Creates a channel buffer for each cpu using the sizes and +- * attributes specified. The created channel buffer files +- * will be named base_filename0...base_filenameN-1. File +- * permissions will be S_IRUSR. +- */ +-struct rchan *relay_open(const char *base_filename, +- struct dentry *parent, +- size_t subbuf_size, +- size_t n_subbufs, +- struct rchan_callbacks *cb) +-{ +- unsigned int i; +- struct rchan *chan; +- char *tmpname; +- int is_global = 0; +- +- if (!base_filename) +- return NULL; +- +- if (!(subbuf_size && n_subbufs)) +- return NULL; +- +- chan = kcalloc(1, sizeof(struct rchan), GFP_KERNEL); +- if (!chan) +- return NULL; +- +- chan->version = RELAYFS_CHANNEL_VERSION; +- chan->n_subbufs = n_subbufs; +- chan->subbuf_size = subbuf_size; +- chan->alloc_size = FIX_SIZE(subbuf_size * n_subbufs); +- setup_callbacks(chan, cb); +- kref_init(&chan->kref); +- +- tmpname = kmalloc(NAME_MAX + 1, GFP_KERNEL); +- if (!tmpname) +- goto free_chan; +- +- for_each_online_cpu(i) { +- sprintf(tmpname, "%s%d", base_filename, i); +- chan->buf[i] = relay_open_buf(chan, tmpname, parent, +- &is_global); +- chan->buf[i]->cpu = i; +- if (!chan->buf[i]) +- goto free_bufs; +- } +- +- kfree(tmpname); +- return chan; +- +-free_bufs: +- for (i = 0; i < NR_CPUS; i++) { +- if (!chan->buf[i]) +- break; +- relay_close_buf(chan->buf[i]); +- if (is_global) +- break; +- } +- kfree(tmpname); +- +-free_chan: +- kref_put(&chan->kref, relay_destroy_channel); +- return NULL; +-} +- +-/** +- * relay_switch_subbuf - switch to a new sub-buffer +- * @buf: channel buffer +- * @length: size of current event +- * +- * Returns either the length passed in or 0 if full. +- +- * Performs sub-buffer-switch tasks such as invoking callbacks, +- * updating padding counts, waking up readers, etc. +- */ +-size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length) +-{ +- void *old, *new; +- size_t old_subbuf, new_subbuf; +- +- if (unlikely(length > buf->chan->subbuf_size)) +- goto toobig; +- +- if (buf->offset != buf->chan->subbuf_size + 1) { +- buf->prev_padding = buf->chan->subbuf_size - buf->offset; +- old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; +- buf->padding[old_subbuf] = buf->prev_padding; +- buf->subbufs_produced++; +- if (waitqueue_active(&buf->read_wait)) { +- PREPARE_WORK(&buf->wake_readers, wakeup_readers, buf); +- schedule_delayed_work(&buf->wake_readers, 1); +- } +- } +- +- old = buf->data; +- new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; +- new = buf->start + new_subbuf * buf->chan->subbuf_size; +- buf->offset = 0; +- if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { +- buf->offset = buf->chan->subbuf_size + 1; +- return 0; +- } +- buf->data = new; +- buf->padding[new_subbuf] = 0; +- +- if (unlikely(length + buf->offset > buf->chan->subbuf_size)) +- goto toobig; +- +- return length; +- +-toobig: +- buf->chan->last_toobig = length; +- return 0; +-} +- +-/** +- * relay_subbufs_consumed - update the buffer's sub-buffers-consumed count +- * @chan: the channel +- * @cpu: the cpu associated with the channel buffer to update +- * @subbufs_consumed: number of sub-buffers to add to current buf's count +- * +- * Adds to the channel buffer's consumed sub-buffer count. +- * subbufs_consumed should be the number of sub-buffers newly consumed, +- * not the total consumed. +- * +- * NOTE: kernel clients don't need to call this function if the channel +- * mode is 'overwrite'. +- */ +-void relay_subbufs_consumed(struct rchan *chan, +- unsigned int cpu, +- size_t subbufs_consumed) +-{ +- struct rchan_buf *buf; +- +- if (!chan) +- return; +- +- if (cpu >= NR_CPUS || !chan->buf[cpu]) +- return; +- +- buf = chan->buf[cpu]; +- buf->subbufs_consumed += subbufs_consumed; +- if (buf->subbufs_consumed > buf->subbufs_produced) +- buf->subbufs_consumed = buf->subbufs_produced; +-} +- +-/** +- * relay_destroy_channel - free the channel struct +- * +- * Should only be called from kref_put(). +- */ +-void relay_destroy_channel(struct kref *kref) +-{ +- struct rchan *chan = container_of(kref, struct rchan, kref); +- kfree(chan); +-} +- +-/** +- * relay_close - close the channel +- * @chan: the channel +- * +- * Closes all channel buffers and frees the channel. +- */ +-void relay_close(struct rchan *chan) +-{ +- unsigned int i; +- struct rchan_buf *prev = NULL; +- +- if (!chan) +- return; +- +- for (i = 0; i < NR_CPUS; i++) { +- if (!chan->buf[i] || chan->buf[i] == prev) +- break; +- relay_close_buf(chan->buf[i]); +- prev = chan->buf[i]; +- } +- +- if (chan->last_toobig) +- printk(KERN_WARNING "relayfs: one or more items not logged " +- "[item size (%Zd) > sub-buffer size (%Zd)]\n", +- chan->last_toobig, chan->subbuf_size); +- +- kref_put(&chan->kref, relay_destroy_channel); +-} +- +-/** +- * relay_flush - close the channel +- * @chan: the channel +- * +- * Flushes all channel buffers i.e. forces buffer switch. +- */ +-void relay_flush(struct rchan *chan) +-{ +- unsigned int i; +- struct rchan_buf *prev = NULL; +- +- if (!chan) +- return; +- +- for (i = 0; i < NR_CPUS; i++) { +- if (!chan->buf[i] || chan->buf[i] == prev) +- break; +- relay_switch_subbuf(chan->buf[i], 0); +- prev = chan->buf[i]; +- } +-} +- +-EXPORT_SYMBOL_GPL(relay_open); +-EXPORT_SYMBOL_GPL(relay_close); +-EXPORT_SYMBOL_GPL(relay_flush); +-EXPORT_SYMBOL_GPL(relay_reset); +-EXPORT_SYMBOL_GPL(relay_subbufs_consumed); +-EXPORT_SYMBOL_GPL(relay_switch_subbuf); +-EXPORT_SYMBOL_GPL(relay_buf_full); +diff --git a/fs/relayfs/relay.h b/fs/relayfs/relay.h +deleted file mode 100644 +index 0993d3e..0000000 +--- a/fs/relayfs/relay.h ++++ /dev/null +@@ -1,8 +0,0 @@ +-#ifndef _RELAY_H +-#define _RELAY_H +- +-extern int relayfs_remove(struct dentry *dentry); +-extern int relay_buf_empty(struct rchan_buf *buf); +-extern void relay_destroy_channel(struct kref *kref); +- +-#endif /* _RELAY_H */ +diff --git a/fs/sysfs/Makefile b/fs/sysfs/Makefile +index 7a1ceb9..7bd4d8f 100644 +--- a/fs/sysfs/Makefile ++++ b/fs/sysfs/Makefile +@@ -4,3 +4,4 @@ + + obj-y := inode.o file.o dir.o symlink.o mount.o bin.o \ + group.o ++obj-$(CONFIG_RELAY) += relay.o +diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c +index 49bd219..52a759b 100644 +--- a/fs/sysfs/dir.c ++++ b/fs/sysfs/dir.c +@@ -87,6 +87,20 @@ static int init_file(struct inode * inod + return 0; + } + ++#ifdef CONFIG_RELAY ++static int init_relay_file(struct inode * inode) ++{ ++ extern struct file_operations relay_file_operations; ++ inode->i_fop = &relay_file_operations; ++ return 0; ++} ++#else ++static int init_relay_file(struct inode * inode) ++{ ++ return -EINVAL; ++} ++#endif ++ + static int init_symlink(struct inode * inode) + { + inode->i_op = &sysfs_symlink_inode_operations; +@@ -165,6 +179,7 @@ int sysfs_create_dir(struct kobject * ko + static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry) + { + struct attribute * attr = NULL; ++ struct relay_attribute * rel_attr = NULL; + struct bin_attribute * bin_attr = NULL; + int (* init) (struct inode *) = NULL; + int error = 0; +@@ -172,6 +187,10 @@ static int sysfs_attach_attr(struct sysf + if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) { + bin_attr = sd->s_element; + attr = &bin_attr->attr; ++ } else if (sd->s_type & SYSFS_KOBJ_RELAY_ATTR) { ++ rel_attr = sd->s_element; ++ attr = &rel_attr->attr; ++ init = init_relay_file; + } else { + attr = sd->s_element; + init = init_file; +@@ -189,6 +208,13 @@ static int sysfs_attach_attr(struct sysf + dentry->d_inode->i_size = bin_attr->size; + dentry->d_inode->i_fop = &bin_fops; + } ++ ++ if (rel_attr) { ++ unsigned int size = rel_attr->subbuf_size * rel_attr->n_subbufs; ++ dentry->d_inode->i_size = ((size - 1) & PAGE_MASK) + PAGE_SIZE; ++ dentry->d_inode->u.generic_ip = rel_attr->rchan_buf; ++ } ++ + dentry->d_op = &sysfs_dentry_ops; + d_rehash(dentry); + +diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c +index 689f7bc..d41cb6d 100644 +--- a/fs/sysfs/inode.c ++++ b/fs/sysfs/inode.c +@@ -174,6 +174,7 @@ const unsigned char * sysfs_get_name(str + { + struct attribute * attr; + struct bin_attribute * bin_attr; ++ struct relay_attribute * rel_attr; + struct sysfs_symlink * sl; + + if (!sd || !sd->s_element) +@@ -192,6 +193,10 @@ const unsigned char * sysfs_get_name(str + bin_attr = sd->s_element; + return bin_attr->attr.name; + ++ case SYSFS_KOBJ_RELAY_ATTR: ++ rel_attr = sd->s_element; ++ return rel_attr->attr.name; ++ + case SYSFS_KOBJ_LINK: + sl = sd->s_element; + return sl->link_name; +diff --git a/fs/sysfs/relay.c b/fs/sysfs/relay.c +new file mode 100644 +index 0000000..f40de18 +--- /dev/null ++++ b/fs/sysfs/relay.c +@@ -0,0 +1,70 @@ ++/* ++ * relay.c - relay channel buffer support for sysfs ++ * ++ * Copyright (C) 2006 Paul Mundt ++ * ++ * This file is subject to the terms and conditions of the GNU General Public ++ * License. See the file "COPYING" in the main directory of this archive ++ * for more details. ++ */ ++#include ++#include ++#include ++#include "sysfs.h" ++ ++static struct dentry * ++sysfs_create_buf_file(const char *filename, struct dentry *dentry, int mode, ++ struct rchan_buf *buf, int *is_global) ++{ ++ struct relay_attribute *attr = (struct relay_attribute *)dentry; ++ struct dentry *parent = attr->kobj->dentry; ++ int ret; ++ ++ attr->attr.mode = mode; ++ attr->rchan_buf = buf; ++ ++ ret = sysfs_add_file(parent, &attr->attr, SYSFS_KOBJ_RELAY_ATTR); ++ if (unlikely(ret != 0)) ++ return NULL; ++ ++ dentry = lookup_one_len(filename, parent, strlen(filename)); ++ if (IS_ERR(dentry)) ++ sysfs_hash_and_remove(parent, filename); ++ ++ return dentry; ++} ++ ++static int sysfs_remove_buf_file(struct dentry *dentry) ++{ ++ sysfs_hash_and_remove(dentry, dentry->d_name.name); ++ return 0; ++} ++ ++struct rchan_callbacks sysfs_rchan_callbacks = { ++ .create_buf_file = sysfs_create_buf_file, ++ .remove_buf_file = sysfs_remove_buf_file, ++}; ++ ++int sysfs_create_relay_file(struct kobject *kobj, struct relay_attribute *attr) ++{ ++ BUG_ON(!kobj || !kobj->dentry || !attr); ++ ++ attr->kobj = kobj; ++ ++ attr->rchan = relay_open(attr->attr.name, (void *)attr, ++ attr->subbuf_size, attr->n_subbufs, ++ &sysfs_rchan_callbacks); ++ if (IS_ERR(attr->rchan)) ++ return PTR_ERR(attr->rchan); ++ ++ return 0; ++} ++EXPORT_SYMBOL_GPL(sysfs_create_relay_file); ++ ++void sysfs_remove_relay_file(struct kobject *kobj, struct relay_attribute *attr) ++{ ++ BUG_ON(!attr); ++ ++ relay_close(attr->rchan); ++} ++EXPORT_SYMBOL_GPL(sysfs_remove_relay_file); +diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h +index 860e7a4..266ce9d 100644 +--- a/include/linux/blkdev.h ++++ b/include/linux/blkdev.h +@@ -22,6 +22,7 @@ typedef struct request_queue request_que + struct elevator_queue; + typedef struct elevator_queue elevator_t; + struct request_pm_state; ++struct blk_trace; + + #define BLKDEV_MIN_RQ 4 + #define BLKDEV_MAX_RQ 128 /* Default maximum */ +@@ -416,6 +417,8 @@ struct request_queue + unsigned int sg_reserved_size; + int node; + ++ struct blk_trace *blk_trace; ++ + /* + * reserved for flush operations + */ +diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h +new file mode 100644 +index 0000000..b34d3e7 +--- /dev/null ++++ b/include/linux/blktrace_api.h +@@ -0,0 +1,277 @@ ++#ifndef BLKTRACE_H ++#define BLKTRACE_H ++ ++#include ++#include ++#include ++ ++/* ++ * Trace categories ++ */ ++enum blktrace_cat { ++ BLK_TC_READ = 1 << 0, /* reads */ ++ BLK_TC_WRITE = 1 << 1, /* writes */ ++ BLK_TC_BARRIER = 1 << 2, /* barrier */ ++ BLK_TC_SYNC = 1 << 3, /* barrier */ ++ BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ ++ BLK_TC_REQUEUE = 1 << 5, /* requeueing */ ++ BLK_TC_ISSUE = 1 << 6, /* issue */ ++ BLK_TC_COMPLETE = 1 << 7, /* completions */ ++ BLK_TC_FS = 1 << 8, /* fs requests */ ++ BLK_TC_PC = 1 << 9, /* pc requests */ ++ BLK_TC_NOTIFY = 1 << 10, /* special message */ ++ ++ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ ++}; ++ ++#define BLK_TC_SHIFT (16) ++#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) ++ ++/* ++ * Basic trace actions ++ */ ++enum blktrace_act { ++ __BLK_TA_QUEUE = 1, /* queued */ ++ __BLK_TA_BACKMERGE, /* back merged to existing rq */ ++ __BLK_TA_FRONTMERGE, /* front merge to existing rq */ ++ __BLK_TA_GETRQ, /* allocated new request */ ++ __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ ++ __BLK_TA_REQUEUE, /* request requeued */ ++ __BLK_TA_ISSUE, /* sent to driver */ ++ __BLK_TA_COMPLETE, /* completed by driver */ ++ __BLK_TA_PLUG, /* queue was plugged */ ++ __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ ++ __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ ++ __BLK_TA_INSERT, /* insert request */ ++ __BLK_TA_SPLIT, /* bio was split */ ++ __BLK_TA_BOUNCE, /* bio was bounced */ ++ __BLK_TA_REMAP, /* bio was remapped */ ++}; ++ ++/* ++ * Trace actions in full. Additionally, read or write is masked ++ */ ++#define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) ++#define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) ++#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) ++#define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_SPLIT (__BLK_TA_SPLIT) ++#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) ++#define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) ++ ++#define BLK_IO_TRACE_MAGIC 0x65617400 ++#define BLK_IO_TRACE_VERSION 0x07 ++ ++/* ++ * The trace itself ++ */ ++struct blk_io_trace { ++ u32 magic; /* MAGIC << 8 | version */ ++ u32 sequence; /* event number */ ++ u64 time; /* in microseconds */ ++ u64 sector; /* disk offset */ ++ u32 bytes; /* transfer length */ ++ u32 action; /* what happened */ ++ u32 pid; /* who did it */ ++ u32 device; /* device number */ ++ u32 cpu; /* on what cpu did it happen */ ++ u16 error; /* completion error */ ++ u16 pdu_len; /* length of data after this trace */ ++}; ++ ++/* ++ * The remap event ++ */ ++struct blk_io_trace_remap { ++ u32 device; ++ u32 __pad; ++ u64 sector; ++}; ++ ++enum { ++ Blktrace_setup = 1, ++ Blktrace_running, ++ Blktrace_stopped, ++}; ++ ++struct blk_trace { ++ int trace_state; ++ struct rchan *rchan; ++ unsigned long *sequence; ++ u16 act_mask; ++ u64 start_lba; ++ u64 end_lba; ++ u32 pid; ++ u32 dev; ++ struct dentry *dir; ++ struct dentry *dropped_file; ++ atomic_t dropped; ++}; ++ ++/* ++ * User setup structure passed with BLKTRACESTART ++ */ ++struct blk_user_trace_setup { ++ char name[BDEVNAME_SIZE]; /* output */ ++ u16 act_mask; /* input */ ++ u32 buf_size; /* input */ ++ u32 buf_nr; /* input */ ++ u64 start_lba; ++ u64 end_lba; ++ u32 pid; ++}; ++ ++#if defined(CONFIG_BLK_DEV_IO_TRACE) ++extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); ++extern void blk_trace_shutdown(request_queue_t *); ++extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); ++ ++/** ++ * blk_add_trace_rq - Add a trace for a request oriented action ++ * @q: queue the io is for ++ * @rq: the source request ++ * @what: the action ++ * ++ * Description: ++ * Records an action against a request. Will log the bio offset + size. ++ * ++ **/ ++static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, ++ u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ int rw = rq->flags & 0x07; ++ ++ if (likely(!bt)) ++ return; ++ ++ if (blk_pc_request(rq)) { ++ what |= BLK_TC_ACT(BLK_TC_PC); ++ __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); ++ } else { ++ what |= BLK_TC_ACT(BLK_TC_FS); ++ __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); ++ } ++} ++ ++/** ++ * blk_add_trace_bio - Add a trace for a bio oriented action ++ * @q: queue the io is for ++ * @bio: the source bio ++ * @what: the action ++ * ++ * Description: ++ * Records an action against a bio. Will log the bio offset + size. ++ * ++ **/ ++static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, ++ u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ ++ if (likely(!bt)) ++ return; ++ ++ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); ++} ++ ++/** ++ * blk_add_trace_generic - Add a trace for a generic action ++ * @q: queue the io is for ++ * @bio: the source bio ++ * @rw: the data direction ++ * @what: the action ++ * ++ * Description: ++ * Records a simple trace ++ * ++ **/ ++static inline void blk_add_trace_generic(struct request_queue *q, ++ struct bio *bio, int rw, u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ ++ if (likely(!bt)) ++ return; ++ ++ if (bio) ++ blk_add_trace_bio(q, bio, what); ++ else ++ __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); ++} ++ ++/** ++ * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload ++ * @q: queue the io is for ++ * @what: the action ++ * @bio: the source bio ++ * @pdu: the integer payload ++ * ++ * Description: ++ * Adds a trace with some integer payload. This might be an unplug ++ * option given as the action, with the depth at unplug time given ++ * as the payload ++ * ++ **/ ++static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, ++ struct bio *bio, unsigned int pdu) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ u64 rpdu = cpu_to_be64(pdu); ++ ++ if (likely(!bt)) ++ return; ++ ++ if (bio) ++ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); ++ else ++ __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); ++} ++ ++/** ++ * blk_add_trace_remap - Add a trace for a remap operation ++ * @q: queue the io is for ++ * @bio: the source bio ++ * @dev: target device ++ * @from: source sector ++ * @to: target sector ++ * ++ * Description: ++ * Device mapper or raid target sometimes need to split a bio because ++ * it spans a stripe (or similar). Add a trace for that action. ++ * ++ **/ ++static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, ++ dev_t dev, sector_t from, sector_t to) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ struct blk_io_trace_remap r; ++ ++ if (likely(!bt)) ++ return; ++ ++ r.device = cpu_to_be32(dev); ++ r.sector = cpu_to_be64(to); ++ ++ __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); ++} ++ ++#else /* !CONFIG_BLK_DEV_IO_TRACE */ ++#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) ++#define blk_trace_shutdown(q) do { } while (0) ++#define blk_add_trace_rq(q, rq, what) do { } while (0) ++#define blk_add_trace_bio(q, rq, what) do { } while (0) ++#define blk_add_trace_generic(q, rq, rw, what) do { } while (0) ++#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) ++#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) ++#endif /* CONFIG_BLK_DEV_IO_TRACE */ ++ ++#endif +diff --git a/include/linux/compat_ioctl.h b/include/linux/compat_ioctl.h +index 8fad50f..a3ed64b 100644 +--- a/include/linux/compat_ioctl.h ++++ b/include/linux/compat_ioctl.h +@@ -97,6 +97,10 @@ COMPATIBLE_IOCTL(BLKRRPART) + COMPATIBLE_IOCTL(BLKFLSBUF) + COMPATIBLE_IOCTL(BLKSECTSET) + COMPATIBLE_IOCTL(BLKSSZGET) ++COMPATIBLE_IOCTL(BLKTRACESTART) ++COMPATIBLE_IOCTL(BLKTRACESTOP) ++COMPATIBLE_IOCTL(BLKTRACESETUP) ++COMPATIBLE_IOCTL(BLKTRACETEARDOWN) + ULONG_IOCTL(BLKRASET) + ULONG_IOCTL(BLKFRASET) + /* RAID */ +diff --git a/include/linux/fs.h b/include/linux/fs.h +index e059da9..c7a63cd 100644 +--- a/include/linux/fs.h ++++ b/include/linux/fs.h +@@ -196,6 +196,10 @@ extern int dir_notify_enable; + #define BLKBSZGET _IOR(0x12,112,size_t) + #define BLKBSZSET _IOW(0x12,113,size_t) + #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ ++#define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) ++#define BLKTRACESTART _IO(0x12,116) ++#define BLKTRACESTOP _IO(0x12,117) ++#define BLKTRACETEARDOWN _IO(0x12,118) + + #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ + #define FIBMAP _IO(0x00,1) /* bmap access */ +diff --git a/include/linux/relay.h b/include/linux/relay.h +new file mode 100644 +index 0000000..0b456ec +--- /dev/null ++++ b/include/linux/relay.h +@@ -0,0 +1,282 @@ ++/* ++ * linux/include/linux/relay.h ++ * ++ * Copyright (C) 2002, 2003 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp ++ * Copyright (C) 1999, 2000, 2001, 2002 - Karim Yaghmour (karim@opersys.com) ++ * ++ * CONFIG_RELAY definitions and declarations ++ */ ++ ++#ifndef _LINUX_RELAY_H ++#define _LINUX_RELAY_H ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++/* Needs a _much_ better name... */ ++#define FIX_SIZE(x) ((((x) - 1) & PAGE_MASK) + PAGE_SIZE) ++ ++/* ++ * Tracks changes to rchan/rchan_buf structs ++ */ ++#define RELAYFS_CHANNEL_VERSION 6 ++ ++/* ++ * Per-cpu relay channel buffer ++ */ ++struct rchan_buf ++{ ++ void *start; /* start of channel buffer */ ++ void *data; /* start of current sub-buffer */ ++ size_t offset; /* current offset into sub-buffer */ ++ size_t subbufs_produced; /* count of sub-buffers produced */ ++ size_t subbufs_consumed; /* count of sub-buffers consumed */ ++ struct rchan *chan; /* associated channel */ ++ wait_queue_head_t read_wait; /* reader wait queue */ ++ struct work_struct wake_readers; /* reader wake-up work struct */ ++ struct dentry *dentry; /* channel file dentry */ ++ struct kref kref; /* channel buffer refcount */ ++ struct page **page_array; /* array of current buffer pages */ ++ unsigned int page_count; /* number of current buffer pages */ ++ unsigned int finalized; /* buffer has been finalized */ ++ size_t *padding; /* padding counts per sub-buffer */ ++ size_t prev_padding; /* temporary variable */ ++ size_t bytes_consumed; /* bytes consumed in cur read subbuf */ ++ unsigned int cpu; /* this buf's cpu */ ++ unsigned int poll_flags; ++} ____cacheline_aligned; ++ ++/* ++ * Relay channel data structure ++ */ ++struct rchan ++{ ++ u32 version; /* the version of this struct */ ++ size_t subbuf_size; /* sub-buffer size */ ++ size_t n_subbufs; /* number of sub-buffers per buffer */ ++ size_t alloc_size; /* total buffer size allocated */ ++ struct rchan_callbacks *cb; /* client callbacks */ ++ struct kref kref; /* channel refcount */ ++ void *private_data; /* for user-defined data */ ++ size_t last_toobig; /* tried to log event > subbuf size */ ++ struct rchan_buf *buf[NR_CPUS]; /* per-cpu channel buffers */ ++}; ++ ++/* ++ * Relay channel client callbacks ++ */ ++struct rchan_callbacks ++{ ++ /* ++ * subbuf_start - called on buffer-switch to a new sub-buffer ++ * @buf: the channel buffer containing the new sub-buffer ++ * @subbuf: the start of the new sub-buffer ++ * @prev_subbuf: the start of the previous sub-buffer ++ * @prev_padding: unused space at the end of previous sub-buffer ++ * ++ * The client should return 1 to continue logging, 0 to stop ++ * logging. ++ * ++ * NOTE: subbuf_start will also be invoked when the buffer is ++ * created, so that the first sub-buffer can be initialized ++ * if necessary. In this case, prev_subbuf will be NULL. ++ * ++ * NOTE: the client can reserve bytes at the beginning of the new ++ * sub-buffer by calling subbuf_start_reserve() in this callback. ++ */ ++ int (*subbuf_start) (struct rchan_buf *buf, ++ void *subbuf, ++ void *prev_subbuf, ++ size_t prev_padding); ++ ++ /* ++ * buf_mapped - relay buffer mmap notification ++ * @buf: the channel buffer ++ * @filp: relay file pointer ++ * ++ * Called when a relay file is successfully mmapped ++ */ ++ void (*buf_mapped)(struct rchan_buf *buf, ++ struct file *filp); ++ ++ /* ++ * buf_unmapped - relay buffer unmap notification ++ * @buf: the channel buffer ++ * @filp: relay file pointer ++ * ++ * Called when a relay file is successfully unmapped ++ */ ++ void (*buf_unmapped)(struct rchan_buf *buf, ++ struct file *filp); ++ /* ++ * create_buf_file - create file to represent a relay channel buffer ++ * @filename: the name of the file to create ++ * @parent: the parent of the file to create ++ * @mode: the mode of the file to create ++ * @buf: the channel buffer ++ * @is_global: outparam - set non-zero if the buffer should be global ++ * ++ * Called during relay_open(), once for each per-cpu buffer, ++ * to allow the client to create a file to be used to ++ * represent the corresponding channel buffer. If the file is ++ * created outside of relay, the parent must also exist in ++ * that filesystem. ++ * ++ * The callback should return the dentry of the file created ++ * to represent the relay buffer. ++ * ++ * Setting the is_global outparam to a non-zero value will ++ * cause relay_open() to create a single global buffer rather ++ * than the default set of per-cpu buffers. ++ * ++ * See Documentation/filesystems/relayfs.txt for more info. ++ */ ++ struct dentry *(*create_buf_file)(const char *filename, ++ struct dentry *parent, ++ int mode, ++ struct rchan_buf *buf, ++ int *is_global); ++ ++ /* ++ * remove_buf_file - remove file representing a relay channel buffer ++ * @dentry: the dentry of the file to remove ++ * ++ * Called during relay_close(), once for each per-cpu buffer, ++ * to allow the client to remove a file used to represent a ++ * channel buffer. ++ * ++ * The callback should return 0 if successful, negative if not. ++ */ ++ int (*remove_buf_file)(struct dentry *dentry); ++}; ++ ++/* ++ * CONFIG_RELAY kernel API, kernel/relay.c ++ */ ++ ++struct rchan *relay_open(const char *base_filename, ++ struct dentry *parent, ++ size_t subbuf_size, ++ size_t n_subbufs, ++ struct rchan_callbacks *cb); ++extern void relay_close(struct rchan *chan); ++extern void relay_flush(struct rchan *chan); ++extern void relay_subbufs_consumed(struct rchan *chan, ++ unsigned int cpu, ++ size_t consumed); ++extern void relay_reset(struct rchan *chan); ++extern int relay_buf_full(struct rchan_buf *buf); ++ ++extern size_t relay_switch_subbuf(struct rchan_buf *buf, ++ size_t length); ++ ++/** ++ * relay_write - write data into the channel ++ * @chan: relay channel ++ * @data: data to be written ++ * @length: number of bytes to write ++ * ++ * Writes data into the current cpu's channel buffer. ++ * ++ * Protects the buffer by disabling interrupts. Use this ++ * if you might be logging from interrupt context. Try ++ * __relay_write() if you know you won't be logging from ++ * interrupt context. ++ */ ++static inline void relay_write(struct rchan *chan, ++ const void *data, ++ size_t length) ++{ ++ unsigned long flags; ++ struct rchan_buf *buf; ++ ++ local_irq_save(flags); ++ buf = chan->buf[smp_processor_id()]; ++ if (unlikely(buf->offset + length > chan->subbuf_size)) ++ length = relay_switch_subbuf(buf, length); ++ memcpy(buf->data + buf->offset, data, length); ++ buf->offset += length; ++ local_irq_restore(flags); ++} ++ ++/** ++ * __relay_write - write data into the channel ++ * @chan: relay channel ++ * @data: data to be written ++ * @length: number of bytes to write ++ * ++ * Writes data into the current cpu's channel buffer. ++ * ++ * Protects the buffer by disabling preemption. Use ++ * relay_write() if you might be logging from interrupt ++ * context. ++ */ ++static inline void __relay_write(struct rchan *chan, ++ const void *data, ++ size_t length) ++{ ++ struct rchan_buf *buf; ++ ++ buf = chan->buf[get_cpu()]; ++ if (unlikely(buf->offset + length > buf->chan->subbuf_size)) ++ length = relay_switch_subbuf(buf, length); ++ memcpy(buf->data + buf->offset, data, length); ++ buf->offset += length; ++ put_cpu(); ++} ++ ++/** ++ * relay_reserve - reserve slot in channel buffer ++ * @chan: relay channel ++ * @length: number of bytes to reserve ++ * ++ * Returns pointer to reserved slot, NULL if full. ++ * ++ * Reserves a slot in the current cpu's channel buffer. ++ * Does not protect the buffer at all - caller must provide ++ * appropriate synchronization. ++ */ ++static inline void *relay_reserve(struct rchan *chan, size_t length) ++{ ++ void *reserved; ++ struct rchan_buf *buf = chan->buf[smp_processor_id()]; ++ ++ if (unlikely(buf->offset + length > buf->chan->subbuf_size)) { ++ length = relay_switch_subbuf(buf, length); ++ if (!length) ++ return NULL; ++ } ++ reserved = buf->data + buf->offset; ++ buf->offset += length; ++ ++ return reserved; ++} ++ ++/** ++ * subbuf_start_reserve - reserve bytes at the start of a sub-buffer ++ * @buf: relay channel buffer ++ * @length: number of bytes to reserve ++ * ++ * Helper function used to reserve bytes at the beginning of ++ * a sub-buffer in the subbuf_start() callback. ++ */ ++static inline void subbuf_start_reserve(struct rchan_buf *buf, ++ size_t length) ++{ ++ BUG_ON(length >= buf->chan->subbuf_size - 1); ++ buf->offset = length; ++} ++ ++/* ++ * exported relay file operations, kernel/relay.c ++ */ ++extern struct file_operations relay_file_operations; ++ ++#endif /* _LINUX_RELAY_H */ ++ +diff --git a/include/linux/sched.h b/include/linux/sched.h +index b6f51e3..d9d465b 100644 +--- a/include/linux/sched.h ++++ b/include/linux/sched.h +@@ -705,6 +705,7 @@ struct task_struct { + prio_array_t *array; + + unsigned short ioprio; ++ unsigned int btrace_seq; + + unsigned long sleep_avg; + unsigned long long timestamp, last_ran; +diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h +index 392da5a..36a078e 100644 +--- a/include/linux/sysfs.h ++++ b/include/linux/sysfs.h +@@ -44,6 +44,16 @@ struct attribute_group { + .show = _name##_show, \ + } + ++#define __ATTR_RELAY(_name,_buffer_size,_nr_buffers) { \ ++ .attr = { \ ++ .owner = THIS_MODULE, \ ++ .name = __stringify(_name), \ ++ .mode = 0400, \ ++ }, \ ++ .subbuf_size = _buffer_size, \ ++ .n_subbufs = _nr_buffers, \ ++} ++ + #define __ATTR_NULL { .attr = { .name = NULL } } + + #define attr_name(_attr) (_attr).attr.name +@@ -60,6 +70,15 @@ struct bin_attribute { + struct vm_area_struct *vma); + }; + ++struct relay_attribute { ++ struct attribute attr; ++ struct rchan *rchan; ++ struct rchan_buf *rchan_buf; ++ struct kobject *kobj; ++ size_t subbuf_size; ++ size_t n_subbufs; ++}; ++ + struct sysfs_ops { + ssize_t (*show)(struct kobject *, struct attribute *,char *); + ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t); +@@ -81,7 +100,23 @@ struct sysfs_dirent { + #define SYSFS_KOBJ_ATTR 0x0004 + #define SYSFS_KOBJ_BIN_ATTR 0x0008 + #define SYSFS_KOBJ_LINK 0x0020 +-#define SYSFS_NOT_PINNED (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR | SYSFS_KOBJ_LINK) ++#define SYSFS_KOBJ_RELAY_ATTR 0x0040 ++#define SYSFS_NOT_PINNED (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR | \ ++ SYSFS_KOBJ_LINK | SYSFS_KOBJ_RELAY_ATTR) ++ ++#if defined(CONFIG_RELAY) && defined(CONFIG_SYSFS) ++int sysfs_create_relay_file(struct kobject *, struct relay_attribute *); ++void sysfs_remove_relay_file(struct kobject *, struct relay_attribute *); ++#else ++static inline int sysfs_create_relay_file(struct kobject *kobj, struct relay_attribute *attr) ++{ ++ return 0; ++} ++ ++static inline void sysfs_remove_relay_file(struct kobject *kobj, struct relay_attribute *attr) ++{ ++} ++#endif /* CONFIG_RELAY && CONFIG_SYSFS */ + + #ifdef CONFIG_SYSFS + +diff --git a/init/Kconfig b/init/Kconfig +index 38416a1..fb74fdd 100644 +--- a/init/Kconfig ++++ b/init/Kconfig +@@ -214,6 +214,17 @@ config CPUSETS + + Say N if unsure. + ++config RELAY ++ bool "Kernel->user space relay support (formerly relayfs)" ++ help ++ This option enables support for relay interface support in ++ certain file systems (such as sysfs, and trivially debugfs). ++ It is designed to provide an efficient mechanism for tools and ++ facilities to relay large amounts of data from kernel space to ++ user space. ++ ++ If unsure, say N. ++ + source "usr/Kconfig" + + config UID16 +diff --git a/kernel/Makefile b/kernel/Makefile +index 4ae0fbd..aebd7a7 100644 +--- a/kernel/Makefile ++++ b/kernel/Makefile +@@ -34,6 +34,7 @@ obj-$(CONFIG_DETECT_SOFTLOCKUP) += softl + obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ + obj-$(CONFIG_SECCOMP) += seccomp.o + obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o ++obj-$(CONFIG_RELAY) += relay.o + + ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) + # According to Alan Modra , the -fno-omit-frame-pointer is +diff --git a/kernel/fork.c b/kernel/fork.c +index fbea12d..f564e9b 100644 +--- a/kernel/fork.c ++++ b/kernel/fork.c +@@ -179,6 +179,7 @@ static struct task_struct *dup_task_stru + /* One for us, one for whoever does the "release_task()" (usually parent) */ + atomic_set(&tsk->usage,2); + atomic_set(&tsk->fs_excl, 0); ++ tsk->btrace_seq = 0; + return tsk; + } + +diff --git a/kernel/relay.c b/kernel/relay.c +new file mode 100644 +index 0000000..db68452 +--- /dev/null ++++ b/kernel/relay.c +@@ -0,0 +1,1013 @@ ++/* ++ * Public API and common code for kernel->userspace relay file support. ++ * ++ * See Documentation/filesystems/relayfs.txt for an overview of relayfs. ++ * ++ * Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp ++ * Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com) ++ * ++ * Moved to kernel/relay.c by Paul Mundt, 2006. ++ * ++ * This file is released under the GPL. ++ */ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++/* ++ * close() vm_op implementation for relay file mapping. ++ */ ++static void relay_file_mmap_close(struct vm_area_struct *vma) ++{ ++ struct rchan_buf *buf = vma->vm_private_data; ++ buf->chan->cb->buf_unmapped(buf, vma->vm_file); ++} ++ ++/* ++ * nopage() vm_op implementation for relay file mapping. ++ */ ++static struct page *relay_buf_nopage(struct vm_area_struct *vma, ++ unsigned long address, ++ int *type) ++{ ++ struct page *page; ++ struct rchan_buf *buf = vma->vm_private_data; ++ unsigned long offset = address - vma->vm_start; ++ ++ if (address > vma->vm_end) ++ return NOPAGE_SIGBUS; /* Disallow mremap */ ++ if (!buf) ++ return NOPAGE_OOM; ++ ++ page = vmalloc_to_page(buf->start + offset); ++ if (!page) ++ return NOPAGE_OOM; ++ get_page(page); ++ ++ if (type) ++ *type = VM_FAULT_MINOR; ++ ++ return page; ++} ++ ++/* ++ * vm_ops for relay file mappings. ++ */ ++static struct vm_operations_struct relay_file_mmap_ops = { ++ .nopage = relay_buf_nopage, ++ .close = relay_file_mmap_close, ++}; ++ ++/** ++ * relay_mmap_buf: - mmap channel buffer to process address space ++ * @buf: relay channel buffer ++ * @vma: vm_area_struct describing memory to be mapped ++ * ++ * Returns 0 if ok, negative on error ++ * ++ * Caller should already have grabbed mmap_sem. ++ */ ++int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) ++{ ++ unsigned long length = vma->vm_end - vma->vm_start; ++ struct file *filp = vma->vm_file; ++ ++ if (!buf) ++ return -EBADF; ++ ++ if (length != (unsigned long)buf->chan->alloc_size) ++ return -EINVAL; ++ ++ vma->vm_ops = &relay_file_mmap_ops; ++ vma->vm_private_data = buf; ++ buf->chan->cb->buf_mapped(buf, filp); ++ ++ return 0; ++} ++ ++/** ++ * relay_alloc_buf - allocate a channel buffer ++ * @buf: the buffer struct ++ * @size: total size of the buffer ++ * ++ * Returns a pointer to the resulting buffer, NULL if unsuccessful. The ++ * passed in size will get page aligned, if it isn't already. ++ */ ++static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size) ++{ ++ void *mem; ++ unsigned int i, j, n_pages; ++ ++ *size = PAGE_ALIGN(*size); ++ n_pages = *size >> PAGE_SHIFT; ++ ++ buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); ++ if (!buf->page_array) ++ return NULL; ++ ++ for (i = 0; i < n_pages; i++) { ++ buf->page_array[i] = alloc_page(GFP_KERNEL); ++ if (unlikely(!buf->page_array[i])) ++ goto depopulate; ++ } ++ mem = vmap(buf->page_array, n_pages, VM_MAP, PAGE_KERNEL); ++ if (!mem) ++ goto depopulate; ++ ++ memset(mem, 0, *size); ++ buf->page_count = n_pages; ++ return mem; ++ ++depopulate: ++ for (j = 0; j < i; j++) ++ __free_page(buf->page_array[j]); ++ kfree(buf->page_array); ++ return NULL; ++} ++ ++/** ++ * relay_create_buf - allocate and initialize a channel buffer ++ * @alloc_size: size of the buffer to allocate ++ * @n_subbufs: number of sub-buffers in the channel ++ * ++ * Returns channel buffer if successful, NULL otherwise ++ */ ++struct rchan_buf *relay_create_buf(struct rchan *chan) ++{ ++ struct rchan_buf *buf = kcalloc(1, sizeof(struct rchan_buf), GFP_KERNEL); ++ if (!buf) ++ return NULL; ++ ++ buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL); ++ if (!buf->padding) ++ goto free_buf; ++ ++ buf->start = relay_alloc_buf(buf, &chan->alloc_size); ++ if (!buf->start) ++ goto free_buf; ++ ++ buf->chan = chan; ++ kref_get(&buf->chan->kref); ++ return buf; ++ ++free_buf: ++ kfree(buf->padding); ++ kfree(buf); ++ return NULL; ++} ++ ++/** ++ * relay_destroy_channel - free the channel struct ++ * ++ * Should only be called from kref_put(). ++ */ ++void relay_destroy_channel(struct kref *kref) ++{ ++ struct rchan *chan = container_of(kref, struct rchan, kref); ++ kfree(chan); ++} ++ ++/** ++ * relay_destroy_buf - destroy an rchan_buf struct and associated buffer ++ * @buf: the buffer struct ++ */ ++void relay_destroy_buf(struct rchan_buf *buf) ++{ ++ struct rchan *chan = buf->chan; ++ unsigned int i; ++ ++ if (likely(buf->start)) { ++ vunmap(buf->start); ++ for (i = 0; i < buf->page_count; i++) ++ __free_page(buf->page_array[i]); ++ kfree(buf->page_array); ++ } ++ kfree(buf->padding); ++ kfree(buf); ++ kref_put(&chan->kref, relay_destroy_channel); ++} ++ ++/** ++ * relay_remove_buf - remove a channel buffer ++ * ++ * Removes the file from the fileystem, which also frees the ++ * rchan_buf_struct and the channel buffer. Should only be called from ++ * kref_put(). ++ */ ++void relay_remove_buf(struct kref *kref) ++{ ++ struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref); ++ buf->chan->cb->remove_buf_file(buf->dentry); ++ relay_destroy_buf(buf); ++} ++ ++/** ++ * relay_buf_empty - boolean, is the channel buffer empty? ++ * @buf: channel buffer ++ * ++ * Returns 1 if the buffer is empty, 0 otherwise. ++ */ ++int relay_buf_empty(struct rchan_buf *buf) ++{ ++ return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1; ++} ++EXPORT_SYMBOL_GPL(relay_buf_empty); ++ ++/** ++ * relay_buf_full - boolean, is the channel buffer full? ++ * @buf: channel buffer ++ * ++ * Returns 1 if the buffer is full, 0 otherwise. ++ */ ++int relay_buf_full(struct rchan_buf *buf) ++{ ++ size_t ready = buf->subbufs_produced - buf->subbufs_consumed; ++ return (ready >= buf->chan->n_subbufs) ? 1 : 0; ++} ++EXPORT_SYMBOL_GPL(relay_buf_full); ++ ++/* ++ * High-level relay kernel API and associated functions. ++ */ ++ ++/* ++ * rchan_callback implementations defining default channel behavior. Used ++ * in place of corresponding NULL values in client callback struct. ++ */ ++ ++/* ++ * subbuf_start() default callback. Does nothing. ++ */ ++static int subbuf_start_default_callback (struct rchan_buf *buf, ++ void *subbuf, ++ void *prev_subbuf, ++ size_t prev_padding) ++{ ++ if (relay_buf_full(buf)) ++ return 0; ++ ++ return 1; ++} ++ ++/* ++ * buf_mapped() default callback. Does nothing. ++ */ ++static void buf_mapped_default_callback(struct rchan_buf *buf, ++ struct file *filp) ++{ ++} ++ ++/* ++ * buf_unmapped() default callback. Does nothing. ++ */ ++static void buf_unmapped_default_callback(struct rchan_buf *buf, ++ struct file *filp) ++{ ++} ++ ++/* ++ * create_buf_file_create() default callback. Does nothing. ++ */ ++static struct dentry *create_buf_file_default_callback(const char *filename, ++ struct dentry *parent, ++ int mode, ++ struct rchan_buf *buf, ++ int *is_global) ++{ ++ return NULL; ++} ++ ++/* ++ * remove_buf_file() default callback. Does nothing. ++ */ ++static int remove_buf_file_default_callback(struct dentry *dentry) ++{ ++ return -EINVAL; ++} ++ ++/* relay channel default callbacks */ ++static struct rchan_callbacks default_channel_callbacks = { ++ .subbuf_start = subbuf_start_default_callback, ++ .buf_mapped = buf_mapped_default_callback, ++ .buf_unmapped = buf_unmapped_default_callback, ++ .create_buf_file = create_buf_file_default_callback, ++ .remove_buf_file = remove_buf_file_default_callback, ++}; ++ ++/** ++ * wakeup_readers - wake up readers waiting on a channel ++ * @private: the channel buffer ++ * ++ * This is the work function used to defer reader waking. The ++ * reason waking is deferred is that calling directly from write ++ * causes problems if you're writing from say the scheduler. ++ */ ++static void wakeup_readers(void *private) ++{ ++ struct rchan_buf *buf = private; ++ wake_up_interruptible(&buf->read_wait); ++} ++ ++/** ++ * __relay_reset - reset a channel buffer ++ * @buf: the channel buffer ++ * @init: 1 if this is a first-time initialization ++ * ++ * See relay_reset for description of effect. ++ */ ++static inline void __relay_reset(struct rchan_buf *buf, unsigned int init) ++{ ++ size_t i; ++ ++ if (init) { ++ init_waitqueue_head(&buf->read_wait); ++ kref_init(&buf->kref); ++ INIT_WORK(&buf->wake_readers, NULL, NULL); ++ } else { ++ cancel_delayed_work(&buf->wake_readers); ++ flush_scheduled_work(); ++ } ++ ++ buf->subbufs_produced = 0; ++ buf->subbufs_consumed = 0; ++ buf->bytes_consumed = 0; ++ buf->finalized = 0; ++ buf->data = buf->start; ++ buf->offset = 0; ++ ++ for (i = 0; i < buf->chan->n_subbufs; i++) ++ buf->padding[i] = 0; ++ ++ buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0); ++} ++ ++/** ++ * relay_reset - reset the channel ++ * @chan: the channel ++ * ++ * This has the effect of erasing all data from all channel buffers ++ * and restarting the channel in its initial state. The buffers ++ * are not freed, so any mappings are still in effect. ++ * ++ * NOTE: Care should be taken that the channel isn't actually ++ * being used by anything when this call is made. ++ */ ++void relay_reset(struct rchan *chan) ++{ ++ unsigned int i; ++ struct rchan_buf *prev = NULL; ++ ++ if (!chan) ++ return; ++ ++ for (i = 0; i < NR_CPUS; i++) { ++ if (!chan->buf[i] || chan->buf[i] == prev) ++ break; ++ __relay_reset(chan->buf[i], 0); ++ prev = chan->buf[i]; ++ } ++} ++EXPORT_SYMBOL_GPL(relay_reset); ++ ++/** ++ * relay_open_buf - create a new relay channel buffer ++ * ++ * Internal - used by relay_open(). ++ */ ++static struct rchan_buf *relay_open_buf(struct rchan *chan, ++ const char *filename, ++ struct dentry *parent, ++ int *is_global) ++{ ++ struct rchan_buf *buf; ++ struct dentry *dentry; ++ ++ if (*is_global) ++ return chan->buf[0]; ++ ++ buf = relay_create_buf(chan); ++ if (!buf) ++ return NULL; ++ ++ /* Create file in fs */ ++ dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR, ++ buf, is_global); ++ if (!dentry) { ++ relay_destroy_buf(buf); ++ return NULL; ++ } ++ ++ buf->dentry = dentry; ++ __relay_reset(buf, 1); ++ ++ return buf; ++} ++ ++/** ++ * relay_close_buf - close a channel buffer ++ * @buf: channel buffer ++ * ++ * Marks the buffer finalized and restores the default callbacks. ++ * The channel buffer and channel buffer data structure are then freed ++ * automatically when the last reference is given up. ++ */ ++static inline void relay_close_buf(struct rchan_buf *buf) ++{ ++ buf->finalized = 1; ++ cancel_delayed_work(&buf->wake_readers); ++ flush_scheduled_work(); ++ kref_put(&buf->kref, relay_remove_buf); ++} ++ ++static inline void setup_callbacks(struct rchan *chan, ++ struct rchan_callbacks *cb) ++{ ++ if (!cb) { ++ chan->cb = &default_channel_callbacks; ++ return; ++ } ++ ++ if (!cb->subbuf_start) ++ cb->subbuf_start = subbuf_start_default_callback; ++ if (!cb->buf_mapped) ++ cb->buf_mapped = buf_mapped_default_callback; ++ if (!cb->buf_unmapped) ++ cb->buf_unmapped = buf_unmapped_default_callback; ++ if (!cb->create_buf_file) ++ cb->create_buf_file = create_buf_file_default_callback; ++ if (!cb->remove_buf_file) ++ cb->remove_buf_file = remove_buf_file_default_callback; ++ chan->cb = cb; ++} ++ ++/** ++ * relay_open - create a new relay channel ++ * @base_filename: base name of files to create ++ * @parent: dentry of parent directory, NULL for root directory ++ * @subbuf_size: size of sub-buffers ++ * @n_subbufs: number of sub-buffers ++ * @cb: client callback functions ++ * ++ * Returns channel pointer if successful, NULL otherwise. ++ * ++ * Creates a channel buffer for each cpu using the sizes and ++ * attributes specified. The created channel buffer files ++ * will be named base_filename0...base_filenameN-1. File ++ * permissions will be S_IRUSR. ++ */ ++struct rchan *relay_open(const char *base_filename, ++ struct dentry *parent, ++ size_t subbuf_size, ++ size_t n_subbufs, ++ struct rchan_callbacks *cb) ++{ ++ unsigned int i; ++ struct rchan *chan; ++ char *tmpname; ++ int is_global = 0; ++ ++ if (!base_filename) ++ return NULL; ++ ++ if (!(subbuf_size && n_subbufs)) ++ return NULL; ++ ++ chan = kcalloc(1, sizeof(struct rchan), GFP_KERNEL); ++ if (!chan) ++ return NULL; ++ ++ chan->version = RELAYFS_CHANNEL_VERSION; ++ chan->n_subbufs = n_subbufs; ++ chan->subbuf_size = subbuf_size; ++ chan->alloc_size = FIX_SIZE(subbuf_size * n_subbufs); ++ setup_callbacks(chan, cb); ++ kref_init(&chan->kref); ++ ++ tmpname = kmalloc(NAME_MAX + 1, GFP_KERNEL); ++ if (!tmpname) ++ goto free_chan; ++ ++ for_each_online_cpu(i) { ++ sprintf(tmpname, "%s%d", base_filename, i); ++ chan->buf[i] = relay_open_buf(chan, tmpname, parent, ++ &is_global); ++ chan->buf[i]->cpu = i; ++ if (!chan->buf[i]) ++ goto free_bufs; ++ } ++ ++ kfree(tmpname); ++ return chan; ++ ++free_bufs: ++ for (i = 0; i < NR_CPUS; i++) { ++ if (!chan->buf[i]) ++ break; ++ relay_close_buf(chan->buf[i]); ++ if (is_global) ++ break; ++ } ++ kfree(tmpname); ++ ++free_chan: ++ kref_put(&chan->kref, relay_destroy_channel); ++ return NULL; ++} ++EXPORT_SYMBOL_GPL(relay_open); ++ ++/** ++ * relay_switch_subbuf - switch to a new sub-buffer ++ * @buf: channel buffer ++ * @length: size of current event ++ * ++ * Returns either the length passed in or 0 if full. ++ * ++ * Performs sub-buffer-switch tasks such as invoking callbacks, ++ * updating padding counts, waking up readers, etc. ++ */ ++size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length) ++{ ++ void *old, *new; ++ size_t old_subbuf, new_subbuf; ++ ++ if (unlikely(length > buf->chan->subbuf_size)) ++ goto toobig; ++ ++ if (buf->offset != buf->chan->subbuf_size + 1) { ++ buf->prev_padding = buf->chan->subbuf_size - buf->offset; ++ old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; ++ buf->padding[old_subbuf] = buf->prev_padding; ++ buf->subbufs_produced++; ++ buf->dentry->d_inode->i_size += buf->chan->subbuf_size - ++ buf->padding[old_subbuf]; ++ buf->poll_flags = POLLMSG; ++ smp_mb(); ++ if (waitqueue_active(&buf->read_wait)) { ++ PREPARE_WORK(&buf->wake_readers, wakeup_readers, buf); ++ schedule_delayed_work(&buf->wake_readers, 1); ++ } ++ } ++ ++ old = buf->data; ++ new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; ++ new = buf->start + new_subbuf * buf->chan->subbuf_size; ++ buf->offset = 0; ++ if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { ++ buf->offset = buf->chan->subbuf_size + 1; ++ return 0; ++ } ++ buf->data = new; ++ buf->padding[new_subbuf] = 0; ++ ++ if (unlikely(length + buf->offset > buf->chan->subbuf_size)) ++ goto toobig; ++ ++ return length; ++ ++toobig: ++ buf->chan->last_toobig = length; ++ return 0; ++} ++EXPORT_SYMBOL_GPL(relay_switch_subbuf); ++ ++/** ++ * relay_subbufs_consumed - update the buffer's sub-buffers-consumed count ++ * @chan: the channel ++ * @cpu: the cpu associated with the channel buffer to update ++ * @subbufs_consumed: number of sub-buffers to add to current buf's count ++ * ++ * Adds to the channel buffer's consumed sub-buffer count. ++ * subbufs_consumed should be the number of sub-buffers newly consumed, ++ * not the total consumed. ++ * ++ * NOTE: kernel clients don't need to call this function if the channel ++ * mode is 'overwrite'. ++ */ ++void relay_subbufs_consumed(struct rchan *chan, ++ unsigned int cpu, ++ size_t subbufs_consumed) ++{ ++ struct rchan_buf *buf; ++ ++ if (!chan) ++ return; ++ ++ if (cpu >= NR_CPUS || !chan->buf[cpu]) ++ return; ++ ++ buf = chan->buf[cpu]; ++ buf->subbufs_consumed += subbufs_consumed; ++ if (buf->subbufs_consumed > buf->subbufs_produced) ++ buf->subbufs_consumed = buf->subbufs_produced; ++} ++EXPORT_SYMBOL_GPL(relay_subbufs_consumed); ++ ++/** ++ * relay_close - close the channel ++ * @chan: the channel ++ * ++ * Closes all channel buffers and frees the channel. ++ */ ++void relay_close(struct rchan *chan) ++{ ++ unsigned int i; ++ struct rchan_buf *prev = NULL; ++ ++ if (!chan) ++ return; ++ ++ for (i = 0; i < NR_CPUS; i++) { ++ if (!chan->buf[i] || chan->buf[i] == prev) ++ break; ++ relay_close_buf(chan->buf[i]); ++ prev = chan->buf[i]; ++ } ++ ++ if (chan->last_toobig) ++ printk(KERN_WARNING "relay: one or more items not logged " ++ "[item size (%Zd) > sub-buffer size (%Zd)]\n", ++ chan->last_toobig, chan->subbuf_size); ++ ++ kref_put(&chan->kref, relay_destroy_channel); ++} ++EXPORT_SYMBOL_GPL(relay_close); ++ ++/** ++ * relay_flush - close the channel ++ * @chan: the channel ++ * ++ * Flushes all channel buffers i.e. forces buffer switch. ++ */ ++void relay_flush(struct rchan *chan) ++{ ++ unsigned int i; ++ struct rchan_buf *prev = NULL; ++ ++ if (!chan) ++ return; ++ ++ for (i = 0; i < NR_CPUS; i++) { ++ if (!chan->buf[i] || chan->buf[i] == prev) ++ break; ++ relay_switch_subbuf(chan->buf[i], 0); ++ prev = chan->buf[i]; ++ } ++} ++EXPORT_SYMBOL_GPL(relay_flush); ++ ++/** ++ * relay_file_open - open file op for relay files ++ * @inode: the inode ++ * @filp: the file ++ * ++ * Increments the channel buffer refcount. ++ */ ++static int relay_file_open(struct inode *inode, struct file *filp) ++{ ++ struct rchan_buf *buf = inode->u.generic_ip; ++ kref_get(&buf->kref); ++ filp->private_data = buf; ++ ++ return 0; ++} ++ ++/** ++ * relay_file_mmap - mmap file op for relay files ++ * @filp: the file ++ * @vma: the vma describing what to map ++ * ++ * Calls upon relay_mmap_buf to map the file into user space. ++ */ ++static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) ++{ ++ struct rchan_buf *buf = filp->private_data; ++ return relay_mmap_buf(buf, vma); ++} ++ ++/** ++ * relay_file_poll - poll file op for relay files ++ * @filp: the file ++ * @wait: poll table ++ * ++ * Poll implemention. ++ */ ++static unsigned int relay_file_poll(struct file *filp, poll_table *wait) ++{ ++ unsigned int mask = 0; ++ struct rchan_buf *buf = filp->private_data; ++ ++ if (buf->finalized) ++ return POLLERR; ++ ++ if (filp->f_mode & FMODE_READ) { ++ poll_wait(filp, &buf->read_wait, wait); ++ if (!relay_buf_empty(buf)) ++ mask |= POLLIN | POLLRDNORM | buf->poll_flags; ++ buf->poll_flags = 0; ++ } ++ ++ return mask; ++} ++ ++/** ++ * relay_file_release - release file op for relay files ++ * @inode: the inode ++ * @filp: the file ++ * ++ * Decrements the channel refcount, as the filesystem is ++ * no longer using it. ++ */ ++static int relay_file_release(struct inode *inode, struct file *filp) ++{ ++ struct rchan_buf *buf = filp->private_data; ++ kref_put(&buf->kref, relay_remove_buf); ++ ++ return 0; ++} ++ ++/** ++ * relay_file_read_consume - update the consumed count for the buffer ++ */ ++static void relay_file_read_consume(struct rchan_buf *buf, ++ size_t read_pos, ++ size_t bytes_consumed) ++{ ++ size_t subbuf_size = buf->chan->subbuf_size; ++ size_t n_subbufs = buf->chan->n_subbufs; ++ size_t read_subbuf; ++ ++ if (buf->bytes_consumed + bytes_consumed > subbuf_size) { ++ relay_subbufs_consumed(buf->chan, buf->cpu, 1); ++ buf->bytes_consumed = 0; ++ } ++ ++ buf->bytes_consumed += bytes_consumed; ++ read_subbuf = read_pos / buf->chan->subbuf_size; ++ if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) { ++ if ((read_subbuf == buf->subbufs_produced % n_subbufs) && ++ (buf->offset == subbuf_size)) ++ return; ++ relay_subbufs_consumed(buf->chan, buf->cpu, 1); ++ buf->bytes_consumed = 0; ++ } ++} ++ ++/** ++ * relay_file_read_avail - boolean, are there unconsumed bytes available? ++ */ ++static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos) ++{ ++ size_t subbuf_size = buf->chan->subbuf_size; ++ size_t n_subbufs = buf->chan->n_subbufs; ++ size_t produced = buf->subbufs_produced; ++ size_t consumed = buf->subbufs_consumed; ++ ++ relay_file_read_consume(buf, read_pos, 0); ++ ++ if (unlikely(buf->offset > subbuf_size)) { ++ if (produced == consumed) ++ return 0; ++ return 1; ++ } ++ ++ if (unlikely(produced - consumed >= n_subbufs)) { ++ consumed = (produced / n_subbufs) * n_subbufs; ++ buf->subbufs_consumed = consumed; ++ } ++ ++ produced = (produced % n_subbufs) * subbuf_size + buf->offset; ++ consumed = (consumed % n_subbufs) * subbuf_size + buf->bytes_consumed; ++ ++ if (consumed > produced) ++ produced += n_subbufs * subbuf_size; ++ ++ if (consumed == produced) ++ return 0; ++ ++ return 1; ++} ++ ++/** ++ * relay_file_read_subbuf_avail - return bytes available in sub-buffer ++ */ ++static size_t relay_file_read_subbuf_avail(size_t read_pos, ++ struct rchan_buf *buf) ++{ ++ size_t padding, avail = 0; ++ size_t read_subbuf, read_offset, write_subbuf, write_offset; ++ size_t subbuf_size = buf->chan->subbuf_size; ++ ++ write_subbuf = (buf->data - buf->start) / subbuf_size; ++ write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset; ++ read_subbuf = read_pos / subbuf_size; ++ read_offset = read_pos % subbuf_size; ++ padding = buf->padding[read_subbuf]; ++ ++ if (read_subbuf == write_subbuf) { ++ if (read_offset + padding < write_offset) ++ avail = write_offset - (read_offset + padding); ++ } else ++ avail = (subbuf_size - padding) - read_offset; ++ ++ return avail; ++} ++ ++/** ++ * relay_file_read_start_pos - find the first available byte to read ++ * ++ * If the read_pos is in the middle of padding, return the ++ * position of the first actually available byte, otherwise ++ * return the original value. ++ */ ++static size_t relay_file_read_start_pos(size_t read_pos, ++ struct rchan_buf *buf) ++{ ++ size_t read_subbuf, padding, padding_start, padding_end; ++ size_t subbuf_size = buf->chan->subbuf_size; ++ size_t n_subbufs = buf->chan->n_subbufs; ++ ++ read_subbuf = read_pos / subbuf_size; ++ padding = buf->padding[read_subbuf]; ++ padding_start = (read_subbuf + 1) * subbuf_size - padding; ++ padding_end = (read_subbuf + 1) * subbuf_size; ++ if (read_pos >= padding_start && read_pos < padding_end) { ++ read_subbuf = (read_subbuf + 1) % n_subbufs; ++ read_pos = read_subbuf * subbuf_size; ++ } ++ ++ return read_pos; ++} ++ ++/** ++ * relay_file_read_end_pos - return the new read position ++ */ ++static size_t relay_file_read_end_pos(struct rchan_buf *buf, ++ size_t read_pos, ++ size_t count) ++{ ++ size_t read_subbuf, padding, end_pos; ++ size_t subbuf_size = buf->chan->subbuf_size; ++ size_t n_subbufs = buf->chan->n_subbufs; ++ ++ read_subbuf = read_pos / subbuf_size; ++ padding = buf->padding[read_subbuf]; ++ if (read_pos % subbuf_size + count + padding == subbuf_size) ++ end_pos = (read_subbuf + 1) * subbuf_size; ++ else ++ end_pos = read_pos + count; ++ if (end_pos >= subbuf_size * n_subbufs) ++ end_pos = 0; ++ ++ return end_pos; ++} ++ ++/** ++ * subbuf_read_actor - read up to one subbuf's worth of data ++ */ ++static int subbuf_read_actor(size_t read_start, ++ struct rchan_buf *buf, ++ size_t avail, ++ read_descriptor_t *desc, ++ read_actor_t actor) ++{ ++ void *from; ++ int ret = 0; ++ ++ from = buf->start + read_start; ++ ret = avail; ++ if (copy_to_user(desc->arg.data, from, avail)) { ++ desc->error = -EFAULT; ++ ret = 0; ++ } ++ desc->arg.data += ret; ++ desc->written += ret; ++ desc->count -= ret; ++ ++ return ret; ++} ++ ++/** ++ * subbuf_send_actor - send up to one subbuf's worth of data ++ */ ++static int subbuf_send_actor(size_t read_start, ++ struct rchan_buf *buf, ++ size_t avail, ++ read_descriptor_t *desc, ++ read_actor_t actor) ++{ ++ unsigned long pidx, poff; ++ unsigned int subbuf_pages; ++ int ret = 0; ++ ++ subbuf_pages = buf->chan->alloc_size >> PAGE_SHIFT; ++ pidx = (read_start / PAGE_SIZE) % subbuf_pages; ++ poff = read_start & ~PAGE_MASK; ++ while (avail) { ++ struct page *p = buf->page_array[pidx]; ++ unsigned int len; ++ ++ len = PAGE_SIZE - poff; ++ if (len > avail) ++ len = avail; ++ ++ len = actor(desc, p, poff, len); ++ if (desc->error) ++ break; ++ ++ avail -= len; ++ ret += len; ++ poff = 0; ++ pidx = (pidx + 1) % subbuf_pages; ++ } ++ ++ return ret; ++} ++ ++typedef int (*subbuf_actor_t) (size_t read_start, ++ struct rchan_buf *buf, ++ size_t avail, ++ read_descriptor_t *desc, ++ read_actor_t actor); ++ ++/** ++ * relay_file_read_subbufs - read count bytes, bridging subbuf boundaries ++ */ ++static inline ssize_t relay_file_read_subbufs(struct file *filp, ++ loff_t *ppos, ++ size_t count, ++ subbuf_actor_t subbuf_actor, ++ read_actor_t actor, ++ void *target) ++{ ++ struct rchan_buf *buf = filp->private_data; ++ size_t read_start, avail; ++ read_descriptor_t desc; ++ int ret; ++ ++ if (!count) ++ return 0; ++ ++ desc.written = 0; ++ desc.count = count; ++ desc.arg.data = target; ++ desc.error = 0; ++ ++ mutex_lock(&filp->f_dentry->d_inode->i_mutex); ++ do { ++ if (!relay_file_read_avail(buf, *ppos)) ++ break; ++ ++ read_start = relay_file_read_start_pos(*ppos, buf); ++ avail = relay_file_read_subbuf_avail(read_start, buf); ++ if (!avail) ++ break; ++ ++ avail = min(desc.count, avail); ++ ret = subbuf_actor(read_start, buf, avail, &desc, actor); ++ if (desc.error < 0) ++ break; ++ ++ if (ret) { ++ relay_file_read_consume(buf, read_start, ret); ++ *ppos = relay_file_read_end_pos(buf, read_start, ret); ++ } ++ } while (desc.count && ret); ++ mutex_unlock(&filp->f_dentry->d_inode->i_mutex); ++ ++ return desc.written; ++} ++ ++static ssize_t relay_file_read(struct file *filp, ++ char __user *buffer, ++ size_t count, ++ loff_t *ppos) ++{ ++ return relay_file_read_subbufs(filp, ppos, count, subbuf_read_actor, ++ NULL, buffer); ++} ++ ++static ssize_t relay_file_sendfile(struct file *filp, ++ loff_t *ppos, ++ size_t count, ++ read_actor_t actor, ++ void *target) ++{ ++ return relay_file_read_subbufs(filp, ppos, count, subbuf_send_actor, ++ actor, target); ++} ++ ++struct file_operations relay_file_operations = { ++ .open = relay_file_open, ++ .poll = relay_file_poll, ++ .mmap = relay_file_mmap, ++ .read = relay_file_read, ++ .llseek = no_llseek, ++ .release = relay_file_release, ++ .sendfile = relay_file_sendfile, ++}; ++EXPORT_SYMBOL_GPL(relay_file_operations); +diff --git a/mm/highmem.c b/mm/highmem.c +index ce2e7e8..d0ea1ee 100644 +--- a/mm/highmem.c ++++ b/mm/highmem.c +@@ -26,6 +26,7 @@ + #include + #include + #include ++#include + #include + + static mempool_t *page_pool, *isa_page_pool; +@@ -483,6 +484,8 @@ void blk_queue_bounce(request_queue_t *q + pool = isa_page_pool; + } + ++ blk_add_trace_bio(q, *bio_orig, BLK_TA_BOUNCE); ++ + /* + * slow path + */