#include <asm/page.h>
#include <linux/task_work.h>
#include <linux/namei.h>
+#include <linux/kref.h>
#include <uapi/linux/ublk_cmd.h>
#define UBLK_MINORS (1U << MINORBITS)
| UBLK_F_USER_RECOVERY \
| UBLK_F_USER_RECOVERY_REISSUE \
| UBLK_F_UNPRIVILEGED_DEV \
- | UBLK_F_CMD_IOCTL_ENCODE)
+ | UBLK_F_CMD_IOCTL_ENCODE \
+ | UBLK_F_USER_COPY)
/* All UBLK_PARAM_TYPE_* should be included here */
#define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | \
struct ublk_rq_data {
struct llist_node node;
- struct callback_head work;
+
+ struct kref ref;
};
struct ublk_uring_cmd_pdu {
__u32 types;
};
+static inline void __ublk_complete_rq(struct request *req);
+static void ublk_complete_rq(struct kref *ref);
+
static dev_t ublk_chr_devt;
-static struct class *ublk_chr_class;
+static const struct class ublk_chr_class = {
+ .name = "ublk-char",
+};
static DEFINE_IDR(ublk_index_idr);
static DEFINE_SPINLOCK(ublk_idr_lock);
static struct miscdevice ublk_misc;
+static inline unsigned ublk_pos_to_hwq(loff_t pos)
+{
+ return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_QID_OFF) &
+ UBLK_QID_BITS_MASK;
+}
+
+static inline unsigned ublk_pos_to_buf_off(loff_t pos)
+{
+ return (pos - UBLKSRV_IO_BUF_OFFSET) & UBLK_IO_BUF_BITS_MASK;
+}
+
+static inline unsigned ublk_pos_to_tag(loff_t pos)
+{
+ return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_TAG_OFF) &
+ UBLK_TAG_BITS_MASK;
+}
+
static void ublk_dev_param_basic_apply(struct ublk_device *ub)
{
struct request_queue *q = ub->ub_disk->queue;
return 0;
}
-static inline bool ublk_can_use_task_work(const struct ublk_queue *ubq)
+static inline bool ublk_support_user_copy(const struct ublk_queue *ubq)
{
- if (IS_BUILTIN(CONFIG_BLK_DEV_UBLK) &&
- !(ubq->flags & UBLK_F_URING_CMD_COMP_IN_TASK))
- return true;
- return false;
+ return ubq->flags & UBLK_F_USER_COPY;
+}
+
+static inline bool ublk_need_req_ref(const struct ublk_queue *ubq)
+{
+ /*
+ * read()/write() is involved in user copy, so request reference
+ * has to be grabbed
+ */
+ return ublk_support_user_copy(ubq);
+}
+
+static inline void ublk_init_req_ref(const struct ublk_queue *ubq,
+ struct request *req)
+{
+ if (ublk_need_req_ref(ubq)) {
+ struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+ kref_init(&data->ref);
+ }
+}
+
+static inline bool ublk_get_req_ref(const struct ublk_queue *ubq,
+ struct request *req)
+{
+ if (ublk_need_req_ref(ubq)) {
+ struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+ return kref_get_unless_zero(&data->ref);
+ }
+
+ return true;
+}
+
+static inline void ublk_put_req_ref(const struct ublk_queue *ubq,
+ struct request *req)
+{
+ if (ublk_need_req_ref(ubq)) {
+ struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+ kref_put(&data->ref, ublk_complete_rq);
+ } else {
+ __ublk_complete_rq(req);
+ }
}
static inline bool ublk_need_get_data(const struct ublk_queue *ubq)
*owner_gid = from_kgid(&init_user_ns, gid);
}
-static int ublk_open(struct block_device *bdev, fmode_t mode)
+static int ublk_open(struct gendisk *disk, blk_mode_t mode)
{
- struct ublk_device *ub = bdev->bd_disk->private_data;
+ struct ublk_device *ub = disk->private_data;
if (capable(CAP_SYS_ADMIN))
return 0;
#define UBLK_MAX_PIN_PAGES 32
-struct ublk_map_data {
- const struct request *rq;
- unsigned long ubuf;
- unsigned int len;
-};
-
struct ublk_io_iter {
struct page *pages[UBLK_MAX_PIN_PAGES];
- unsigned pg_off; /* offset in the 1st page in pages */
- int nr_pages; /* how many page pointers in pages */
struct bio *bio;
struct bvec_iter iter;
};
-static inline unsigned ublk_copy_io_pages(struct ublk_io_iter *data,
- unsigned max_bytes, bool to_vm)
+/* return how many pages are copied */
+static void ublk_copy_io_pages(struct ublk_io_iter *data,
+ size_t total, size_t pg_off, int dir)
{
- const unsigned total = min_t(unsigned, max_bytes,
- PAGE_SIZE - data->pg_off +
- ((data->nr_pages - 1) << PAGE_SHIFT));
unsigned done = 0;
unsigned pg_idx = 0;
while (done < total) {
struct bio_vec bv = bio_iter_iovec(data->bio, data->iter);
- const unsigned int bytes = min3(bv.bv_len, total - done,
- (unsigned)(PAGE_SIZE - data->pg_off));
+ unsigned int bytes = min3(bv.bv_len, (unsigned)total - done,
+ (unsigned)(PAGE_SIZE - pg_off));
void *bv_buf = bvec_kmap_local(&bv);
void *pg_buf = kmap_local_page(data->pages[pg_idx]);
- if (to_vm)
- memcpy(pg_buf + data->pg_off, bv_buf, bytes);
+ if (dir == ITER_DEST)
+ memcpy(pg_buf + pg_off, bv_buf, bytes);
else
- memcpy(bv_buf, pg_buf + data->pg_off, bytes);
+ memcpy(bv_buf, pg_buf + pg_off, bytes);
kunmap_local(pg_buf);
kunmap_local(bv_buf);
/* advance page array */
- data->pg_off += bytes;
- if (data->pg_off == PAGE_SIZE) {
+ pg_off += bytes;
+ if (pg_off == PAGE_SIZE) {
pg_idx += 1;
- data->pg_off = 0;
+ pg_off = 0;
}
done += bytes;
data->iter = data->bio->bi_iter;
}
}
+}
- return done;
+static bool ublk_advance_io_iter(const struct request *req,
+ struct ublk_io_iter *iter, unsigned int offset)
+{
+ struct bio *bio = req->bio;
+
+ for_each_bio(bio) {
+ if (bio->bi_iter.bi_size > offset) {
+ iter->bio = bio;
+ iter->iter = bio->bi_iter;
+ bio_advance_iter(iter->bio, &iter->iter, offset);
+ return true;
+ }
+ offset -= bio->bi_iter.bi_size;
+ }
+ return false;
}
-static int ublk_copy_user_pages(struct ublk_map_data *data, bool to_vm)
+/*
+ * Copy data between request pages and io_iter, and 'offset'
+ * is the start point of linear offset of request.
+ */
+static size_t ublk_copy_user_pages(const struct request *req,
+ unsigned offset, struct iov_iter *uiter, int dir)
{
- const unsigned int gup_flags = to_vm ? FOLL_WRITE : 0;
- const unsigned long start_vm = data->ubuf;
- unsigned int done = 0;
- struct ublk_io_iter iter = {
- .pg_off = start_vm & (PAGE_SIZE - 1),
- .bio = data->rq->bio,
- .iter = data->rq->bio->bi_iter,
- };
- const unsigned int nr_pages = round_up(data->len +
- (start_vm & (PAGE_SIZE - 1)), PAGE_SIZE) >> PAGE_SHIFT;
-
- while (done < nr_pages) {
- const unsigned to_pin = min_t(unsigned, UBLK_MAX_PIN_PAGES,
- nr_pages - done);
- unsigned i, len;
-
- iter.nr_pages = get_user_pages_fast(start_vm +
- (done << PAGE_SHIFT), to_pin, gup_flags,
- iter.pages);
- if (iter.nr_pages <= 0)
- return done == 0 ? iter.nr_pages : done;
- len = ublk_copy_io_pages(&iter, data->len, to_vm);
- for (i = 0; i < iter.nr_pages; i++) {
- if (to_vm)
+ struct ublk_io_iter iter;
+ size_t done = 0;
+
+ if (!ublk_advance_io_iter(req, &iter, offset))
+ return 0;
+
+ while (iov_iter_count(uiter) && iter.bio) {
+ unsigned nr_pages;
+ ssize_t len;
+ size_t off;
+ int i;
+
+ len = iov_iter_get_pages2(uiter, iter.pages,
+ iov_iter_count(uiter),
+ UBLK_MAX_PIN_PAGES, &off);
+ if (len <= 0)
+ return done;
+
+ ublk_copy_io_pages(&iter, len, off, dir);
+ nr_pages = DIV_ROUND_UP(len + off, PAGE_SIZE);
+ for (i = 0; i < nr_pages; i++) {
+ if (dir == ITER_DEST)
set_page_dirty(iter.pages[i]);
put_page(iter.pages[i]);
}
- data->len -= len;
- done += iter.nr_pages;
+ done += len;
}
return done;
{
const unsigned int rq_bytes = blk_rq_bytes(req);
+ if (ublk_support_user_copy(ubq))
+ return rq_bytes;
+
/*
* no zero copy, we delay copy WRITE request data into ublksrv
* context and the big benefit is that pinning pages in current
* context is pretty fast, see ublk_pin_user_pages
*/
if (ublk_need_map_req(req)) {
- struct ublk_map_data data = {
- .rq = req,
- .ubuf = io->addr,
- .len = rq_bytes,
- };
+ struct iov_iter iter;
+ struct iovec iov;
+ const int dir = ITER_DEST;
- ublk_copy_user_pages(&data, true);
+ import_single_range(dir, u64_to_user_ptr(io->addr), rq_bytes,
+ &iov, &iter);
- return rq_bytes - data.len;
+ return ublk_copy_user_pages(req, 0, &iter, dir);
}
return rq_bytes;
}
{
const unsigned int rq_bytes = blk_rq_bytes(req);
+ if (ublk_support_user_copy(ubq))
+ return rq_bytes;
+
if (ublk_need_unmap_req(req)) {
- struct ublk_map_data data = {
- .rq = req,
- .ubuf = io->addr,
- .len = io->res,
- };
+ struct iov_iter iter;
+ struct iovec iov;
+ const int dir = ITER_SOURCE;
WARN_ON_ONCE(io->res > rq_bytes);
- ublk_copy_user_pages(&data, false);
-
- return io->res - data.len;
+ import_single_range(dir, u64_to_user_ptr(io->addr), io->res,
+ &iov, &iter);
+ return ublk_copy_user_pages(req, 0, &iter, dir);
}
return rq_bytes;
}
}
/* todo: handle partial completion */
-static void ublk_complete_rq(struct request *req)
+static inline void __ublk_complete_rq(struct request *req)
{
struct ublk_queue *ubq = req->mq_hctx->driver_data;
struct ublk_io *io = &ubq->ios[req->tag];
unsigned int unmapped_bytes;
blk_status_t res = BLK_STS_OK;
+ /* called from ublk_abort_queue() code path */
+ if (io->flags & UBLK_IO_FLAG_ABORTED) {
+ res = BLK_STS_IOERR;
+ goto exit;
+ }
+
/* failed read IO if nothing is read */
if (!io->res && req_op(req) == REQ_OP_READ)
io->res = -EIO;
blk_mq_end_request(req, res);
}
+static void ublk_complete_rq(struct kref *ref)
+{
+ struct ublk_rq_data *data = container_of(ref, struct ublk_rq_data,
+ ref);
+ struct request *req = blk_mq_rq_from_pdu(data);
+
+ __ublk_complete_rq(req);
+}
+
/*
* Since __ublk_rq_task_work always fails requests immediately during
* exiting, __ublk_fail_req() is only called from abort context during
if (ublk_queue_can_use_recovery_reissue(ubq))
blk_mq_requeue_request(req, false);
else
- blk_mq_end_request(req, BLK_STS_IOERR);
+ ublk_put_req_ref(ubq, req);
}
}
mapped_bytes >> 9;
}
+ ublk_init_req_ref(ubq, req);
ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);
}
ublk_forward_io_cmds(ubq, issue_flags);
}
-static void ublk_rq_task_work_fn(struct callback_head *work)
-{
- struct ublk_rq_data *data = container_of(work,
- struct ublk_rq_data, work);
- struct request *req = blk_mq_rq_from_pdu(data);
- struct ublk_queue *ubq = req->mq_hctx->driver_data;
- unsigned issue_flags = IO_URING_F_UNLOCKED;
-
- ublk_forward_io_cmds(ubq, issue_flags);
-}
-
static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
{
struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq);
*/
if (unlikely(io->flags & UBLK_IO_FLAG_ABORTED)) {
ublk_abort_io_cmds(ubq);
- } else if (ublk_can_use_task_work(ubq)) {
- if (task_work_add(ubq->ubq_daemon, &data->work,
- TWA_SIGNAL_NO_IPI))
- ublk_abort_io_cmds(ubq);
} else {
struct io_uring_cmd *cmd = io->cmd;
struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
return 0;
}
-static int ublk_init_rq(struct blk_mq_tag_set *set, struct request *req,
- unsigned int hctx_idx, unsigned int numa_node)
-{
- struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
-
- init_task_work(&data->work, ublk_rq_task_work_fn);
- return 0;
-}
-
static const struct blk_mq_ops ublk_mq_ops = {
.queue_rq = ublk_queue_rq,
.init_hctx = ublk_init_hctx,
- .init_request = ublk_init_rq,
.timeout = ublk_timeout,
};
req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag);
if (req && likely(!blk_should_fake_timeout(req->q)))
- ublk_complete_rq(req);
+ ublk_put_req_ref(ubq, req);
}
/*
return 0;
}
+static inline void ublk_fill_io_cmd(struct ublk_io *io,
+ struct io_uring_cmd *cmd, unsigned long buf_addr)
+{
+ io->cmd = cmd;
+ io->flags |= UBLK_IO_FLAG_ACTIVE;
+ io->addr = buf_addr;
+}
+
static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
unsigned int issue_flags,
const struct ublksrv_io_cmd *ub_cmd)
^ (_IOC_NR(cmd_op) == UBLK_IO_NEED_GET_DATA))
goto out;
+ if (ublk_support_user_copy(ubq) && ub_cmd->addr) {
+ ret = -EINVAL;
+ goto out;
+ }
+
ret = ublk_check_cmd_op(cmd_op);
if (ret)
goto out;
*/
if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)
goto out;
- /* FETCH_RQ has to provide IO buffer if NEED GET DATA is not enabled */
- if (!ub_cmd->addr && !ublk_need_get_data(ubq))
- goto out;
- io->cmd = cmd;
- io->flags |= UBLK_IO_FLAG_ACTIVE;
- io->addr = ub_cmd->addr;
+ if (!ublk_support_user_copy(ubq)) {
+ /*
+ * FETCH_RQ has to provide IO buffer if NEED GET
+ * DATA is not enabled
+ */
+ if (!ub_cmd->addr && !ublk_need_get_data(ubq))
+ goto out;
+ }
+
+ ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
ublk_mark_io_ready(ub, ubq);
break;
case UBLK_IO_COMMIT_AND_FETCH_REQ:
req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag);
- /*
- * COMMIT_AND_FETCH_REQ has to provide IO buffer if NEED GET DATA is
- * not enabled or it is Read IO.
- */
- if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || req_op(req) == REQ_OP_READ))
- goto out;
+
if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
goto out;
- io->addr = ub_cmd->addr;
- io->flags |= UBLK_IO_FLAG_ACTIVE;
- io->cmd = cmd;
+
+ if (!ublk_support_user_copy(ubq)) {
+ /*
+ * COMMIT_AND_FETCH_REQ has to provide IO buffer if
+ * NEED GET DATA is not enabled or it is Read IO.
+ */
+ if (!ub_cmd->addr && (!ublk_need_get_data(ubq) ||
+ req_op(req) == REQ_OP_READ))
+ goto out;
+ }
+ ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
ublk_commit_completion(ub, ub_cmd);
break;
case UBLK_IO_NEED_GET_DATA:
if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
goto out;
- io->addr = ub_cmd->addr;
- io->cmd = cmd;
- io->flags |= UBLK_IO_FLAG_ACTIVE;
+ ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
ublk_handle_need_get_data(ub, ub_cmd->q_id, ub_cmd->tag);
break;
default:
return -EIOCBQUEUED;
}
+static inline struct request *__ublk_check_and_get_req(struct ublk_device *ub,
+ struct ublk_queue *ubq, int tag, size_t offset)
+{
+ struct request *req;
+
+ if (!ublk_need_req_ref(ubq))
+ return NULL;
+
+ req = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], tag);
+ if (!req)
+ return NULL;
+
+ if (!ublk_get_req_ref(ubq, req))
+ return NULL;
+
+ if (unlikely(!blk_mq_request_started(req) || req->tag != tag))
+ goto fail_put;
+
+ if (!ublk_rq_has_data(req))
+ goto fail_put;
+
+ if (offset > blk_rq_bytes(req))
+ goto fail_put;
+
+ return req;
+fail_put:
+ ublk_put_req_ref(ubq, req);
+ return NULL;
+}
+
static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
{
/*
return __ublk_ch_uring_cmd(cmd, issue_flags, &ub_cmd);
}
+static inline bool ublk_check_ubuf_dir(const struct request *req,
+ int ubuf_dir)
+{
+ /* copy ubuf to request pages */
+ if (req_op(req) == REQ_OP_READ && ubuf_dir == ITER_SOURCE)
+ return true;
+
+ /* copy request pages to ubuf */
+ if (req_op(req) == REQ_OP_WRITE && ubuf_dir == ITER_DEST)
+ return true;
+
+ return false;
+}
+
+static struct request *ublk_check_and_get_req(struct kiocb *iocb,
+ struct iov_iter *iter, size_t *off, int dir)
+{
+ struct ublk_device *ub = iocb->ki_filp->private_data;
+ struct ublk_queue *ubq;
+ struct request *req;
+ size_t buf_off;
+ u16 tag, q_id;
+
+ if (!ub)
+ return ERR_PTR(-EACCES);
+
+ if (!user_backed_iter(iter))
+ return ERR_PTR(-EACCES);
+
+ if (ub->dev_info.state == UBLK_S_DEV_DEAD)
+ return ERR_PTR(-EACCES);
+
+ tag = ublk_pos_to_tag(iocb->ki_pos);
+ q_id = ublk_pos_to_hwq(iocb->ki_pos);
+ buf_off = ublk_pos_to_buf_off(iocb->ki_pos);
+
+ if (q_id >= ub->dev_info.nr_hw_queues)
+ return ERR_PTR(-EINVAL);
+
+ ubq = ublk_get_queue(ub, q_id);
+ if (!ubq)
+ return ERR_PTR(-EINVAL);
+
+ if (tag >= ubq->q_depth)
+ return ERR_PTR(-EINVAL);
+
+ req = __ublk_check_and_get_req(ub, ubq, tag, buf_off);
+ if (!req)
+ return ERR_PTR(-EINVAL);
+
+ if (!req->mq_hctx || !req->mq_hctx->driver_data)
+ goto fail;
+
+ if (!ublk_check_ubuf_dir(req, dir))
+ goto fail;
+
+ *off = buf_off;
+ return req;
+fail:
+ ublk_put_req_ref(ubq, req);
+ return ERR_PTR(-EACCES);
+}
+
+static ssize_t ublk_ch_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ struct ublk_queue *ubq;
+ struct request *req;
+ size_t buf_off;
+ size_t ret;
+
+ req = ublk_check_and_get_req(iocb, to, &buf_off, ITER_DEST);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ ret = ublk_copy_user_pages(req, buf_off, to, ITER_DEST);
+ ubq = req->mq_hctx->driver_data;
+ ublk_put_req_ref(ubq, req);
+
+ return ret;
+}
+
+static ssize_t ublk_ch_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct ublk_queue *ubq;
+ struct request *req;
+ size_t buf_off;
+ size_t ret;
+
+ req = ublk_check_and_get_req(iocb, from, &buf_off, ITER_SOURCE);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ ret = ublk_copy_user_pages(req, buf_off, from, ITER_SOURCE);
+ ubq = req->mq_hctx->driver_data;
+ ublk_put_req_ref(ubq, req);
+
+ return ret;
+}
+
static const struct file_operations ublk_ch_fops = {
.owner = THIS_MODULE,
.open = ublk_ch_open,
.release = ublk_ch_release,
.llseek = no_llseek,
+ .read_iter = ublk_ch_read_iter,
+ .write_iter = ublk_ch_write_iter,
.uring_cmd = ublk_ch_uring_cmd,
.mmap = ublk_ch_mmap,
};
dev->parent = ublk_misc.this_device;
dev->devt = MKDEV(MAJOR(ublk_chr_devt), minor);
- dev->class = ublk_chr_class;
+ dev->class = &ublk_chr_class;
dev->release = ublk_cdev_rel;
device_initialize(dev);
if (ublksrv_pid <= 0)
return -EINVAL;
- wait_for_completion_interruptible(&ub->completion);
+ if (wait_for_completion_interruptible(&ub->completion) != 0)
+ return -EINTR;
schedule_delayed_work(&ub->monitor_work, UBLK_DAEMON_MONITOR_PERIOD);
*/
ub->dev_info.flags &= UBLK_F_ALL;
- if (!IS_BUILTIN(CONFIG_BLK_DEV_UBLK))
- ub->dev_info.flags |= UBLK_F_URING_CMD_COMP_IN_TASK;
+ ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE |
+ UBLK_F_URING_CMD_COMP_IN_TASK;
- ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE;
+ /* GET_DATA isn't needed any more with USER_COPY */
+ if (ub->dev_info.flags & UBLK_F_USER_COPY)
+ ub->dev_info.flags &= ~UBLK_F_NEED_GET_DATA;
/* We are not ready to support zero copy */
ub->dev_info.flags &= ~UBLK_F_SUPPORT_ZERO_COPY;
* - the device number is freed already, we will not find this
* device via ublk_get_device_from_id()
*/
- wait_event_interruptible(ublk_idr_wq, ublk_idr_freed(idx));
-
+ if (wait_event_interruptible(ublk_idr_wq, ublk_idr_freed(idx)))
+ return -EINTR;
return 0;
}
pr_devel("%s: Waiting for new ubq_daemons(nr: %d) are ready, dev id %d...\n",
__func__, ub->dev_info.nr_hw_queues, header->dev_id);
/* wait until new ubq_daemon sending all FETCH_REQ */
- wait_for_completion_interruptible(&ub->completion);
+ if (wait_for_completion_interruptible(&ub->completion))
+ return -EINTR;
+
pr_devel("%s: All new ubq_daemons(nr: %d) are ready, dev id %d\n",
__func__, ub->dev_info.nr_hw_queues, header->dev_id);
return ret;
}
+static int ublk_ctrl_get_features(struct io_uring_cmd *cmd)
+{
+ const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe);
+ void __user *argp = (void __user *)(unsigned long)header->addr;
+ u64 features = UBLK_F_ALL & ~UBLK_F_SUPPORT_ZERO_COPY;
+
+ if (header->len != UBLK_FEATURES_LEN || !header->addr)
+ return -EINVAL;
+
+ if (copy_to_user(argp, &features, UBLK_FEATURES_LEN))
+ return -EFAULT;
+
+ return 0;
+}
+
/*
* All control commands are sent via /dev/ublk-control, so we have to check
* the destination device's permission
case UBLK_CMD_GET_DEV_INFO2:
case UBLK_CMD_GET_QUEUE_AFFINITY:
case UBLK_CMD_GET_PARAMS:
+ case (_IOC_NR(UBLK_U_CMD_GET_FEATURES)):
mask = MAY_READ;
break;
case UBLK_CMD_START_DEV:
if (ret)
goto out;
+ if (cmd_op == UBLK_U_CMD_GET_FEATURES) {
+ ret = ublk_ctrl_get_features(cmd);
+ goto out;
+ }
+
if (_IOC_NR(cmd_op) != UBLK_CMD_ADD_DEV) {
ret = -ENODEV;
ub = ublk_get_device_from_id(header->dev_id);
{
int ret;
+ BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET +
+ UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET);
+
init_waitqueue_head(&ublk_idr_wq);
ret = misc_register(&ublk_misc);
if (ret)
goto unregister_mis;
- ublk_chr_class = class_create("ublk-char");
- if (IS_ERR(ublk_chr_class)) {
- ret = PTR_ERR(ublk_chr_class);
+ ret = class_register(&ublk_chr_class);
+ if (ret)
goto free_chrdev_region;
- }
+
return 0;
free_chrdev_region:
idr_for_each_entry(&ublk_index_idr, ub, id)
ublk_remove(ub);
- class_destroy(ublk_chr_class);
+ class_unregister(&ublk_chr_class);
misc_deregister(&ublk_misc);
idr_destroy(&ublk_index_idr);
projects / linux-block.git / blobdiff