From: Jens Axboe Date: Mon, 7 Aug 2006 10:25:08 +0000 (+0200) Subject: [PATCH] Fixup relayfs references and kill kernel patch X-Git-Tag: blktrace-0.99.2~32 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=e33da1d51a823921d769125320b977a967be4030;p=blktrace.git [PATCH] Fixup relayfs references and kill kernel patch 2.6.17 has shipped and has support for blktrace, so no need to carry around the older 2.6.16 patch anymore. --- diff --git a/doc/blktrace.tex b/doc/blktrace.tex index a81e2ee..fb8181d 100644 --- a/doc/blktrace.tex +++ b/doc/blktrace.tex @@ -104,23 +104,23 @@ and then down to \emph{Support for tracing block io actions} and hit Y. Install the new kernel (and modules\ldots) and reboot. -\subsection{\label{sec:mount}Mounting the RelayFS file system} +\subsection{\label{sec:mount}Mounting the debugfs file system} -blktrace utilizes files under the Relay file system, and thus must have -the mount point set up -- mounted on the directory /relay. To do this +blktrace utilizes files under the debug file system, and thus must have +the mount point set up -- mounted on the directory /debug. To do this one may do either of the following: \begin{enumerate} \item Manually mount after each boot: \begin{verbatim} -% mount -t relayfs relayfs /relay +% mount -t debugfs debugfs /debug \end{verbatim} \item Add an entry into /etc/fstab, and have it done automatically at each boot\footnote{Note: after adding the entry to /etc/fstab, you could then mount the directory this time only by doing: \% mount /relay}: \begin{verbatim} -relay /relay relayfs default 0 0 +debug /debug debugfs default 0 0 \end{verbatim} \end{enumerate} @@ -333,15 +333,15 @@ Total (65,160): \newpage\section{\label{sec:blktrace-ug}blktrace User Guide} The \emph{blktrace} utility extracts event traces from the kernel (via -the relay file system). Some background details concerning the run-time -behaviour of blktrace will help to understand some of the more arcane -command line options: +the relaying through the debug file system). Some background details +concerning the run-time behaviour of blktrace will help to understand some +of the more arcane command line options: \begin{itemize} \item blktrace receives data from the kernel in buffers passed up - through the Relay file system (RelayFS). Each device being traced has - a file created in the mounted directory for the RelayFS, which defaults - to \emph{/relay} -- this can be overridden with the \emph{-r} command + through the debug file system (relay). Each device being traced has + a file created in the mounted directory for the debugfs, which defaults + to \emph{/debug} -- this can be overridden with the \emph{-r} command line argument. \item blktrace defaults to collecting \emph{all} events that can be @@ -353,7 +353,7 @@ command line options: representation of the filter mask.) \item As noted above, the events are passed up via a series of buffers - stored into RelayFS files. The size and number of buffers can be + stored into debugfs files. The size and number of buffers can be specified via the \emph{-b} and \emph{-n} arguments respectively. \item blktrace stores the extracted data into files stored in the @@ -390,7 +390,7 @@ Short & Long & Description \\ \hline\hline -k & --kill & Kill on-going trace \\ \hline -n \emph{num-sub} & --num-sub=\emph{num-sub} & Specifies number of buffers to use \\ \hline -o \emph{file} & --output=\emph{file} & Prepend \emph{file} to output file name(s) \\ \hline --r \emph{rel-path} & --relay=\emph{rel-path} & Specifies RelayFS mount point \\ \hline +-r \emph{rel-path} & --relay=\emph{rel-path} & Specifies debugfs mount point \\ \hline -V & --version & Outputs version \\ \hline -w \emph{seconds} & --stopwatch=\emph{seconds} & Sets run time to the number of seconds specified \\ \hline \end{tabular} diff --git a/kernel/blk-trace-2.6.16-A0 b/kernel/blk-trace-2.6.16-A0 deleted file mode 100644 index da1a7e6..0000000 --- a/kernel/blk-trace-2.6.16-A0 +++ /dev/null @@ -1,3950 +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..c824644 ---- /dev/null -+++ b/block/blktrace.c -@@ -0,0 +1,539 @@ -+/* -+ * 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 unsigned int root_users; -+ -+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(); -+ if (--root_users == 0) -+ 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) -+ root_users++; -+ else -+ 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) { -+ (void) 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; -+ relay_flush(bt->rchan); -+ 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 0ef2971..7233ab8 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 -@@ -1556,8 +1557,10 @@ 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); -@@ -1621,14 +1624,21 @@ 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); - } - -@@ -1636,6 +1646,9 @@ 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); - } - -@@ -1758,6 +1771,9 @@ 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); - } - -@@ -2109,6 +2125,8 @@ rq_starved: - - rq_init(q, rq); - rq->rl = rl; -+ -+ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ); - out: - return rq; - } -@@ -2137,6 +2155,8 @@ 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(); -@@ -2190,6 +2210,8 @@ 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); - -@@ -2824,6 +2846,8 @@ 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; -@@ -2839,6 +2863,8 @@ 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; - -@@ -2956,6 +2982,7 @@ 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. */ -@@ -2982,6 +3009,8 @@ 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]; - -@@ -3014,6 +3043,15 @@ 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); - } -@@ -3133,6 +3171,8 @@ 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-$(CONFIG_XFS_FS) += xfs/ -diff --git a/fs/bio.c b/fs/bio.c -index 1f3bb50..0dd0d81 100644 ---- a/fs/bio.c -+++ b/fs/bio.c -@@ -25,6 +25,7 @@ - #include - #include - #include -+#include - #include /* for struct sg_iovec */ - - #define BIO_POOL_SIZE 256 -@@ -1095,6 +1096,9 @@ struct bio_pair *bio_split(struct bio *b - if (!bp) - return bp; - -+ blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi, -+ bi->bi_sector + first_sectors); -+ - BUG_ON(bi->bi_vcnt != 1); - BUG_ON(bi->bi_idx != 0); - atomic_set(&bp->cnt, 3); -diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c -index c666769..7c031f0 100644 ---- a/fs/compat_ioctl.c -+++ b/fs/compat_ioctl.c -@@ -72,6 +72,7 @@ - #include - #include - #include -+#include - - #include /* siocdevprivate_ioctl */ - #include -diff --git a/fs/relayfs/Makefile b/fs/relayfs/Makefile -deleted file mode 100644 -index e76e182..0000000 ---- a/fs/relayfs/Makefile -+++ /dev/null -@@ -1,4 +0,0 @@ --obj-$(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/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 ae7dfb7..efb518f 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 128d008..37da58b 100644 ---- a/include/linux/fs.h -+++ b/include/linux/fs.h -@@ -197,6 +197,10 @@ 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..4bcc153 ---- /dev/null -+++ b/include/linux/relay.h -@@ -0,0 +1,281 @@ -+/* -+ * 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 */ -+} ____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 62e6314..e60a91d 100644 ---- a/include/linux/sched.h -+++ b/include/linux/sched.h -@@ -706,6 +706,7 @@ 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/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 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 ccdfbb1..d35e3ee 100644 ---- a/kernel/fork.c -+++ b/kernel/fork.c -@@ -181,6 +181,7 @@ 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..c37e29b ---- /dev/null -+++ b/kernel/relay.c -@@ -0,0 +1,1011 @@ -+/* -+ * 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]; -+ 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; -+ } -+ -+ 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 - */