From e56f81e0b01ef4e45292d8c1e19edd4d09724e14 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 15 Oct 2015 14:10:50 +0200 Subject: [PATCH] dm: refactor ioctl handling This moves the call to blkdev_ioctl and the argument checking to DM core code, and only leaves a callout to find the block device to operate on in the targets. This simplifies the code and allows us to pass through ioctl-like command using other methods in the next patch. Also split out a helper around calling the prepare_ioctl method that will be reused for persistent reservation handling. Signed-off-by: Christoph Hellwig Signed-off-by: Mike Snitzer --- drivers/md/dm-flakey.c | 16 +++++----- drivers/md/dm-linear.c | 14 ++++----- drivers/md/dm-log-writes.c | 13 ++++----- drivers/md/dm-mpath.c | 29 ++++++++---------- drivers/md/dm-switch.c | 21 ++++++------- drivers/md/dm-verity.c | 15 +++++----- drivers/md/dm.c | 55 ++++++++++++++++++++++++++--------- include/linux/device-mapper.h | 6 ++-- 8 files changed, 94 insertions(+), 75 deletions(-) diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c index 645e8b4f808e..09e2afcafd2d 100644 --- a/drivers/md/dm-flakey.c +++ b/drivers/md/dm-flakey.c @@ -373,20 +373,20 @@ static void flakey_status(struct dm_target *ti, status_type_t type, } } -static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg) +static int flakey_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct flakey_c *fc = ti->private; - struct dm_dev *dev = fc->dev; - int r = 0; + + *bdev = fc->dev->bdev; /* * Only pass ioctls through if the device sizes match exactly. */ if (fc->start || - ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - - return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg); + ti->len != i_size_read((*bdev)->bd_inode) >> SECTOR_SHIFT) + return 1; + return 0; } static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) @@ -405,7 +405,7 @@ static struct target_type flakey_target = { .map = flakey_map, .end_io = flakey_end_io, .status = flakey_status, - .ioctl = flakey_ioctl, + .prepare_ioctl = flakey_prepare_ioctl, .iterate_devices = flakey_iterate_devices, }; diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index 436f5c9b6aea..de52864d60fa 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -116,21 +116,21 @@ static void linear_status(struct dm_target *ti, status_type_t type, } } -static int linear_ioctl(struct dm_target *ti, unsigned int cmd, - unsigned long arg) +static int linear_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct linear_c *lc = (struct linear_c *) ti->private; struct dm_dev *dev = lc->dev; - int r = 0; + + *bdev = dev->bdev; /* * Only pass ioctls through if the device sizes match exactly. */ if (lc->start || ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - - return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg); + return 1; + return 0; } static int linear_iterate_devices(struct dm_target *ti, @@ -149,7 +149,7 @@ static struct target_type linear_target = { .dtr = linear_dtr, .map = linear_map, .status = linear_status, - .ioctl = linear_ioctl, + .prepare_ioctl = linear_prepare_ioctl, .iterate_devices = linear_iterate_devices, }; diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c index b2912dbac8bc..624589d51c2c 100644 --- a/drivers/md/dm-log-writes.c +++ b/drivers/md/dm-log-writes.c @@ -714,20 +714,19 @@ static void log_writes_status(struct dm_target *ti, status_type_t type, } } -static int log_writes_ioctl(struct dm_target *ti, unsigned int cmd, - unsigned long arg) +static int log_writes_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct log_writes_c *lc = ti->private; struct dm_dev *dev = lc->dev; - int r = 0; + *bdev = dev->bdev; /* * Only pass ioctls through if the device sizes match exactly. */ if (ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - - return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg); + return 1; + return 0; } static int log_writes_iterate_devices(struct dm_target *ti, @@ -782,7 +781,7 @@ static struct target_type log_writes_target = { .map = log_writes_map, .end_io = normal_end_io, .status = log_writes_status, - .ioctl = log_writes_ioctl, + .prepare_ioctl = log_writes_prepare_ioctl, .message = log_writes_message, .iterate_devices = log_writes_iterate_devices, .io_hints = log_writes_io_hints, diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index bdc96cd838b8..77066a199984 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -1533,18 +1533,14 @@ out: return r; } -static int multipath_ioctl(struct dm_target *ti, unsigned int cmd, - unsigned long arg) +static int multipath_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct multipath *m = ti->private; struct pgpath *pgpath; - struct block_device *bdev; - fmode_t mode; unsigned long flags; int r; - bdev = NULL; - mode = 0; r = 0; spin_lock_irqsave(&m->lock, flags); @@ -1555,23 +1551,17 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd, pgpath = m->current_pgpath; if (pgpath) { - bdev = pgpath->path.dev->bdev; - mode = pgpath->path.dev->mode; + *bdev = pgpath->path.dev->bdev; + *mode = pgpath->path.dev->mode; } if ((pgpath && m->queue_io) || (!pgpath && m->queue_if_no_path)) r = -ENOTCONN; - else if (!bdev) + else if (!*bdev) r = -EIO; spin_unlock_irqrestore(&m->lock, flags); - /* - * Only pass ioctls through if the device sizes match exactly. - */ - if (!r && ti->len != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - if (r == -ENOTCONN && !fatal_signal_pending(current)) { spin_lock_irqsave(&m->lock, flags); if (!m->current_pg) { @@ -1584,7 +1574,12 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd, dm_table_run_md_queue_async(m->ti->table); } - return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg); + /* + * Only pass ioctls through if the device sizes match exactly. + */ + if (!r && ti->len != i_size_read((*bdev)->bd_inode) >> SECTOR_SHIFT) + return 1; + return r; } static int multipath_iterate_devices(struct dm_target *ti, @@ -1700,7 +1695,7 @@ static struct target_type multipath_target = { .resume = multipath_resume, .status = multipath_status, .message = multipath_message, - .ioctl = multipath_ioctl, + .prepare_ioctl = multipath_prepare_ioctl, .iterate_devices = multipath_iterate_devices, .busy = multipath_busy, }; diff --git a/drivers/md/dm-switch.c b/drivers/md/dm-switch.c index 50fca469cafd..b1285753a5d4 100644 --- a/drivers/md/dm-switch.c +++ b/drivers/md/dm-switch.c @@ -511,27 +511,24 @@ static void switch_status(struct dm_target *ti, status_type_t type, * * Passthrough all ioctls to the path for sector 0 */ -static int switch_ioctl(struct dm_target *ti, unsigned cmd, - unsigned long arg) +static int switch_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct switch_ctx *sctx = ti->private; - struct block_device *bdev; - fmode_t mode; unsigned path_nr; - int r = 0; path_nr = switch_get_path_nr(sctx, 0); - bdev = sctx->path_list[path_nr].dmdev->bdev; - mode = sctx->path_list[path_nr].dmdev->mode; + *bdev = sctx->path_list[path_nr].dmdev->bdev; + *mode = sctx->path_list[path_nr].dmdev->mode; /* * Only pass ioctls through if the device sizes match exactly. */ - if (ti->len + sctx->path_list[path_nr].start != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - - return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg); + if (ti->len + sctx->path_list[path_nr].start != + i_size_read((*bdev)->bd_inode) >> SECTOR_SHIFT) + return 1; + return 0; } static int switch_iterate_devices(struct dm_target *ti, @@ -560,7 +557,7 @@ static struct target_type switch_target = { .map = switch_map, .message = switch_message, .status = switch_status, - .ioctl = switch_ioctl, + .prepare_ioctl = switch_prepare_ioctl, .iterate_devices = switch_iterate_devices, }; diff --git a/drivers/md/dm-verity.c b/drivers/md/dm-verity.c index edc624bccf9a..ccf41886ebcf 100644 --- a/drivers/md/dm-verity.c +++ b/drivers/md/dm-verity.c @@ -631,18 +631,17 @@ static void verity_status(struct dm_target *ti, status_type_t type, } } -static int verity_ioctl(struct dm_target *ti, unsigned cmd, - unsigned long arg) +static int verity_prepare_ioctl(struct dm_target *ti, + struct block_device **bdev, fmode_t *mode) { struct dm_verity *v = ti->private; - int r = 0; + + *bdev = v->data_dev->bdev; if (v->data_start || ti->len != i_size_read(v->data_dev->bdev->bd_inode) >> SECTOR_SHIFT) - r = scsi_verify_blk_ioctl(NULL, cmd); - - return r ? : __blkdev_driver_ioctl(v->data_dev->bdev, v->data_dev->mode, - cmd, arg); + return 1; + return 0; } static int verity_iterate_devices(struct dm_target *ti, @@ -965,7 +964,7 @@ static struct target_type verity_target = { .dtr = verity_dtr, .map = verity_map, .status = verity_status, - .ioctl = verity_ioctl, + .prepare_ioctl = verity_prepare_ioctl, .iterate_devices = verity_iterate_devices, .io_hints = verity_io_hints, }; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 77ebb985154c..9b3fe5be0cee 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -555,18 +555,16 @@ static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) return dm_get_geometry(md, geo); } -static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, - unsigned int cmd, unsigned long arg) +static int dm_get_live_table_for_ioctl(struct mapped_device *md, + struct dm_target **tgt, struct block_device **bdev, + fmode_t *mode, int *srcu_idx) { - struct mapped_device *md = bdev->bd_disk->private_data; - int srcu_idx; struct dm_table *map; - struct dm_target *tgt; - int r = -ENOTTY; + int r; retry: - map = dm_get_live_table(md, &srcu_idx); - + r = -ENOTTY; + map = dm_get_live_table(md, srcu_idx); if (!map || !dm_table_get_size(map)) goto out; @@ -574,8 +572,9 @@ retry: if (dm_table_get_num_targets(map) != 1) goto out; - tgt = dm_table_get_target(map, 0); - if (!tgt->type->ioctl) + *tgt = dm_table_get_target(map, 0); + + if (!(*tgt)->type->prepare_ioctl) goto out; if (dm_suspended_md(md)) { @@ -583,16 +582,46 @@ retry: goto out; } - r = tgt->type->ioctl(tgt, cmd, arg); + r = (*tgt)->type->prepare_ioctl(*tgt, bdev, mode); + if (r < 0) + goto out; + + return r; out: - dm_put_live_table(md, srcu_idx); - + dm_put_live_table(md, *srcu_idx); if (r == -ENOTCONN) { msleep(10); goto retry; } + return r; +} +static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, + unsigned int cmd, unsigned long arg) +{ + struct mapped_device *md = bdev->bd_disk->private_data; + struct dm_target *tgt; + int srcu_idx, r; + + r = dm_get_live_table_for_ioctl(md, &tgt, &bdev, &mode, &srcu_idx); + if (r < 0) + return r; + + if (r > 0) { + /* + * Target determined this ioctl is being issued against + * a logical partition of the parent bdev; so extra + * validation is needed. + */ + r = scsi_verify_blk_ioctl(NULL, cmd); + if (r) + goto out; + } + + r = __blkdev_driver_ioctl(bdev, mode, cmd, arg); +out: + dm_put_live_table(md, srcu_idx); return r; } diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 76d23fa8c7d3..ec1c61c87d89 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -79,8 +79,8 @@ typedef void (*dm_status_fn) (struct dm_target *ti, status_type_t status_type, typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv); -typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd, - unsigned long arg); +typedef int (*dm_prepare_ioctl_fn) (struct dm_target *ti, + struct block_device **bdev, fmode_t *mode); /* * These iteration functions are typically used to check (and combine) @@ -156,7 +156,7 @@ struct target_type { dm_resume_fn resume; dm_status_fn status; dm_message_fn message; - dm_ioctl_fn ioctl; + dm_prepare_ioctl_fn prepare_ioctl; dm_busy_fn busy; dm_iterate_devices_fn iterate_devices; dm_io_hints_fn io_hints;