LinuxLists.cc - clean up is partition checks

2020-09-03 05:42:13

Subject: clean up is partition checks

2020-09-03 05:42:29

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 9/9] vsprintf: use bd_partno in bdev_name

No need to go through the hd_struct to find the partition number.

Signed-off-by: Christoph Hellwig <[email protected]>
---
lib/vsprintf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index afb9521ddf9197..14c9a6af1b239a 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -940,13 +940,13 @@ char *bdev_name(char *buf, char *end, struct block_device *bdev,

hd = bdev->bd_disk;
buf = string(buf, end, hd->disk_name, spec);
- if (bdev->bd_part->partno) {
+ if (bdev->bd_partno) {
if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
if (buf < end)
*buf = 'p';
buf++;
}
- buf = number(buf, end, bdev->bd_part->partno, spec);
+ buf = number(buf, end, bdev->bd_partno, spec);
}
return buf;
}
--
2.28.0

2020-09-03 05:42:46

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 8/9] block: use bd_partno in bdevname

No need to go through the hd_struct to find the partition number.

Signed-off-by: Christoph Hellwig <[email protected]>
---
block/genhd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/genhd.c b/block/genhd.c
index 081f1039d9367f..771aa56b1a8c3d 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -85,7 +85,7 @@ char *disk_name(struct gendisk *hd, int partno, char *buf)

const char *bdevname(struct block_device *bdev, char *buf)
{
- return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
+ return disk_name(bdev->bd_disk, bdev->bd_partno, buf);
}
EXPORT_SYMBOL(bdevname);

--
2.28.0

2020-09-03 05:43:03

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 6/9] drbd: don't set ->bd_contains

The ->bd_contains field is set by __blkdev_get and drivers have no
business manipulating it.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/block/drbd/drbd_main.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 04b6bde9419d2a..bd8b129196d49a 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2766,8 +2766,6 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
disk->private_data = device;

device->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
- /* we have no partitions. we contain only ourselves. */
- device->this_bdev->bd_contains = device->this_bdev;

blk_queue_write_cache(q, true, true);
/* Setting the max_hw_sectors to an odd value of 8kibyte here
--
2.28.0

2020-09-03 05:43:10

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 7/9] target/iblock: fix holder printing in iblock_show_configfs_dev_params

bd_contains is never NULL for an open block device. In addition ibd_bd
is always set to a block device that was exclusively opened by the
target code, so the holder is guranteed to be ib_dev as well.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/target/target_core_iblock.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 1c181d31f4c872..f2bd2e207e0b36 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -611,9 +611,8 @@ static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
bl += sprintf(b + bl, " ");
if (bd) {
bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
- MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
- "" : (bd->bd_holder == ib_dev) ?
- "CLAIMED: IBLOCK" : "CLAIMED: OS");
+ MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
+ "CLAIMED: IBLOCK");
} else {
bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
}
--
2.28.0

2020-09-03 05:43:30

by Christoph Hellwig

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Subject: [PATCH 5/9] drbd: don't detour through bd_contains for the gendisk

bd_disk is set on all block devices, including those for partitions.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/block/drbd/drbd_receiver.c | 2 +-
drivers/block/drbd/drbd_worker.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 422363daa6180b..2d16fb0905999d 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -2789,7 +2789,7 @@ bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector,

bool drbd_rs_c_min_rate_throttle(struct drbd_device *device)
{
- struct gendisk *disk = device->ldev->backing_bdev->bd_contains->bd_disk;
+ struct gendisk *disk = device->ldev->backing_bdev->bd_disk;
unsigned long db, dt, dbdt;
unsigned int c_min_rate;
int curr_events;
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 7c903de5c4e103..9107b109ba7bcb 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1672,7 +1672,7 @@ void drbd_resync_after_changed(struct drbd_device *device)

void drbd_rs_controller_reset(struct drbd_device *device)
{
- struct gendisk *disk = device->ldev->backing_bdev->bd_contains->bd_disk;
+ struct gendisk *disk = device->ldev->backing_bdev->bd_disk;
struct fifo_buffer *plan;

atomic_set(&device->rs_sect_in, 0);
--
2.28.0

2020-09-03 05:43:34

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 4/9] md: don't detour through bd_contains for the gendisk

bd_disk is set on all block devices, including those for partitions.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/md/md.c | 2 +-
drivers/md/md.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3f33562d10d6f5..5a0fd93769a70e 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8444,7 +8444,7 @@ static int is_mddev_idle(struct mddev *mddev, int init)
idle = 1;
rcu_read_lock();
rdev_for_each_rcu(rdev, mddev) {
- struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
+ struct gendisk *disk = rdev->bdev->bd_disk;
curr_events = (int)part_stat_read_accum(&disk->part0, sectors) -
atomic_read(&disk->sync_io);
/* sync IO will cause sync_io to increase before the disk_stats
diff --git a/drivers/md/md.h b/drivers/md/md.h
index f9e2ccdd22c478..2175a5ac4f7c68 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -551,7 +551,7 @@ extern void mddev_unlock(struct mddev *mddev);

static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
{
- atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
+ atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
}

static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
--
2.28.0

2020-09-03 05:44:07

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 2/9] block: add a bdev_is_partition helper

Add a littler helper to make the somewhat arcane bd_contains checks a
little more obvious.

Signed-off-by: Christoph Hellwig <[email protected]>
---
block/blk-lib.c | 2 +-
block/ioctl.c | 4 ++--
block/scsi_ioctl.c | 2 +-
drivers/ide/ide-ioctls.c | 4 ++--
drivers/md/dm-table.c | 2 +-
drivers/mmc/core/block.c | 2 +-
drivers/s390/block/dasd_ioctl.c | 8 ++++----
fs/nfsd/blocklayout.c | 4 ++--
include/linux/blkdev.h | 9 +++++++--
kernel/trace/blktrace.c | 2 +-
10 files changed, 22 insertions(+), 17 deletions(-)

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 0d1811e57ac704..e90614fd8d6a42 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -64,7 +64,7 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
return -EINVAL;

/* In case the discard request is in a partition */
- if (bdev->bd_partno)
+ if (bdev_is_partition(bdev))
part_offset = bdev->bd_part->start_sect;

while (nr_sects) {
diff --git a/block/ioctl.c b/block/ioctl.c
index bdb3bbb253d9f8..e4af3df9d28a68 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -23,7 +23,7 @@ static int blkpg_do_ioctl(struct block_device *bdev,
return -EACCES;
if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
return -EFAULT;
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
return -EINVAL;

if (p.pno <= 0)
@@ -94,7 +94,7 @@ static int blkdev_reread_part(struct block_device *bdev)
{
int ret;

- if (!disk_part_scan_enabled(bdev->bd_disk) || bdev != bdev->bd_contains)
+ if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index ef722f04f88a93..3bb4571385ce21 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -854,7 +854,7 @@ EXPORT_SYMBOL(scsi_cmd_ioctl);

int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
{
- if (bd && bd == bd->bd_contains)
+ if (bd && !bdev_is_partition(bd))
return 0;

if (capable(CAP_SYS_RAWIO))
diff --git a/drivers/ide/ide-ioctls.c b/drivers/ide/ide-ioctls.c
index 09491098047bff..58994da10c0664 100644
--- a/drivers/ide/ide-ioctls.c
+++ b/drivers/ide/ide-ioctls.c
@@ -49,7 +49,7 @@ int ide_setting_ioctl(ide_drive_t *drive, struct block_device *bdev,
return err >= 0 ? put_user_long(err, arg) : err;

set_val:
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
err = -EINVAL;
else {
if (!capable(CAP_SYS_ADMIN))
@@ -257,7 +257,7 @@ int generic_ide_ioctl(ide_drive_t *drive, struct block_device *bdev,
switch (cmd) {
case HDIO_OBSOLETE_IDENTITY:
case HDIO_GET_IDENTITY:
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
return -EINVAL;
return ide_get_identity_ioctl(drive, cmd, argp);
case HDIO_GET_NICE:
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 5edc3079e7c199..af156256e511ff 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -903,7 +903,7 @@ static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
struct request_queue *q = bdev_get_queue(bdev);

/* request-based cannot stack on partitions! */
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
return false;

return queue_is_mq(q);
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index fa313b63413547..8d3df0be0355ce 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -723,7 +723,7 @@ static int mmc_blk_check_blkdev(struct block_device *bdev)
* whole block device, not on a partition. This prevents overspray
* between sibling partitions.
*/
- if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
+ if (!capable(CAP_SYS_RAWIO) || bdev_is_partition(bdev))
return -EPERM;
return 0;
}
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index faaf5596e31c12..cb6427fb9f3d16 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -277,7 +277,7 @@ dasd_ioctl_format(struct block_device *bdev, void __user *argp)
dasd_put_device(base);
return -EFAULT;
}
- if (bdev != bdev->bd_contains) {
+ if (bdev_is_partition(bdev)) {
pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
dev_name(&base->cdev->dev));
dasd_put_device(base);
@@ -304,7 +304,7 @@ static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
base = dasd_device_from_gendisk(bdev->bd_disk);
if (!base)
return -ENODEV;
- if (bdev != bdev->bd_contains) {
+ if (bdev_is_partition(bdev)) {
pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
dev_name(&base->cdev->dev));
rc = -EINVAL;
@@ -362,7 +362,7 @@ static int dasd_ioctl_release_space(struct block_device *bdev, void __user *argp
rc = -EROFS;
goto out_err;
}
- if (bdev != bdev->bd_contains) {
+ if (bdev_is_partition(bdev)) {
pr_warn("%s: The specified DASD is a partition and tracks cannot be released\n",
dev_name(&base->cdev->dev));
rc = -EINVAL;
@@ -540,7 +540,7 @@ dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)

if (!capable(CAP_SYS_ADMIN))
return -EACCES;
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
// ro setting is not allowed for partitions
return -EINVAL;
if (get_user(intval, (int __user *)argp))
diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
index 311e5ce80cfc27..a07c39c94bbd03 100644
--- a/fs/nfsd/blocklayout.c
+++ b/fs/nfsd/blocklayout.c
@@ -170,7 +170,7 @@ nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
struct nfs4_client *clp,
struct nfsd4_getdeviceinfo *gdp)
{
- if (sb->s_bdev != sb->s_bdev->bd_contains)
+ if (bdev_is_partition(sb->s_bdev))
return nfserr_inval;
return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
}
@@ -382,7 +382,7 @@ nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
struct nfs4_client *clp,
struct nfsd4_getdeviceinfo *gdp)
{
- if (sb->s_bdev != sb->s_bdev->bd_contains)
+ if (bdev_is_partition(sb->s_bdev))
return nfserr_inval;
return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
}
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7575fa0aae6e5c..0006a78ebc5dde 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1341,6 +1341,11 @@ static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,

extern int blk_verify_command(unsigned char *cmd, fmode_t mode);

+static inline bool bdev_is_partition(struct block_device *bdev)
+{
+ return bdev->bd_partno;
+}
+
enum blk_default_limits {
BLK_MAX_SEGMENTS = 128,
BLK_SAFE_MAX_SECTORS = 255,
@@ -1457,7 +1462,7 @@ static inline int bdev_alignment_offset(struct block_device *bdev)

if (q->limits.misaligned)
return -1;
- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
return queue_limit_alignment_offset(&q->limits,
bdev->bd_part->start_sect);
return q->limits.alignment_offset;
@@ -1498,7 +1503,7 @@ static inline int bdev_discard_alignment(struct block_device *bdev)
{
struct request_queue *q = bdev_get_queue(bdev);

- if (bdev != bdev->bd_contains)
+ if (bdev_is_partition(bdev))
return queue_limit_discard_alignment(&q->limits,
bdev->bd_part->start_sect);
return q->limits.discard_alignment;
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 4b3a42fc3b24f1..157758a88773b9 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -527,7 +527,7 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
* and scsi-generic block devices we create a temporary new debugfs
* directory that will be removed once the trace ends.
*/
- if (bdev && bdev == bdev->bd_contains)
+ if (bdev && !bdev_is_partition(bdev))
dir = q->debugfs_dir;
else
bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);
--
2.28.0

2020-09-03 05:44:26

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 3/9] md: compare bd_disk instead of bd_contains

To check for partitions of the same disk bd_contains works as well, but
bd_disk is way more obvious.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/md/md.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9562ef598ae1f4..3f33562d10d6f5 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2322,8 +2322,7 @@ static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
test_bit(Journal, &rdev2->flags) ||
rdev2->raid_disk == -1)
continue;
- if (rdev->bdev->bd_contains ==
- rdev2->bdev->bd_contains) {
+ if (rdev->bdev->bd_disk == rdev2->bdev->bd_disk) {
rcu_read_unlock();
return 1;
}
@@ -5944,8 +5943,8 @@ int md_run(struct mddev *mddev)
rdev_for_each(rdev, mddev)
rdev_for_each(rdev2, mddev) {
if (rdev < rdev2 &&
- rdev->bdev->bd_contains ==
- rdev2->bdev->bd_contains) {
+ rdev->bdev->bd_disk ==
+ rdev2->bdev->bd_disk) {
pr_warn("%s: WARNING: %s appears to be on the same physical disk as %s.\n",
mdname(mddev),
bdevname(rdev->bdev,b),
--
2.28.0

2020-09-03 05:45:04

by Christoph Hellwig

[permalink] [raw]

Subject: [PATCH 1/9] Documentation/hdio: fix up obscure bd_contains references

bd_contains is an implementation detail and should not be mentioned in
a userspace API documentation.

Signed-off-by: Christoph Hellwig <[email protected]>
---
Documentation/userspace-api/ioctl/hdio.rst | 24 +++++++++++-----------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/Documentation/userspace-api/ioctl/hdio.rst b/Documentation/userspace-api/ioctl/hdio.rst
index e822e3dff1769b..817371bf94e948 100644
--- a/Documentation/userspace-api/ioctl/hdio.rst
+++ b/Documentation/userspace-api/ioctl/hdio.rst
@@ -181,7 +181,7 @@ HDIO_SET_UNMASKINTR

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
@@ -231,7 +231,7 @@ HDIO_SET_MULTCOUNT

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range supported by disk.
- EBUSY Controller busy or blockmode already set.
@@ -295,7 +295,7 @@ HDIO_GET_IDENTITY
the ATA specification.

error returns:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- ENOMSG IDENTIFY DEVICE information not available

notes:
@@ -355,7 +355,7 @@ HDIO_SET_KEEPSETTINGS

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
@@ -1055,7 +1055,7 @@ HDIO_SET_32BIT

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 3]
- EBUSY Controller busy
@@ -1085,7 +1085,7 @@ HDIO_SET_NOWERR

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
@@ -1113,7 +1113,7 @@ HDIO_SET_DMA

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
@@ -1141,7 +1141,7 @@ HDIO_SET_PIO_MODE

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 255]
- EBUSY Controller busy
@@ -1237,7 +1237,7 @@ HDIO_SET_WCACHE

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
@@ -1265,7 +1265,7 @@ HDIO_SET_ACOUSTIC

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 254]
- EBUSY Controller busy
@@ -1305,7 +1305,7 @@ HDIO_SET_ADDRESS

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 2]
- EBUSY Controller busy
@@ -1331,7 +1331,7 @@ HDIO_SET_IDE_SCSI

error return:
- - EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ - EINVAL Called on a partition instead of the whole disk device
- EACCES Access denied: requires CAP_SYS_ADMIN
- EINVAL value out of range [0 1]
- EBUSY Controller busy
--
2.28.0

2020-09-03 08:21:12

by Ulf Hansson

[permalink] [raw]

Subject: Re: [PATCH 2/9] block: add a bdev_is_partition helper

On Thu, 3 Sep 2020 at 07:42, Christoph Hellwig <[email protected]> wrote:
>
> Add a littler helper to make the somewhat arcane bd_contains checks a
> little more obvious.
>
> Signed-off-by: Christoph Hellwig <[email protected]>

Not sure why we have both "bd_contains" and "bd_partno", nevertheless,
feel free to add:

Acked-by: Ulf Hansson <[email protected]>

Kind regards
Uffe

> ---
> block/blk-lib.c | 2 +-
> block/ioctl.c | 4 ++--
> block/scsi_ioctl.c | 2 +-
> drivers/ide/ide-ioctls.c | 4 ++--
> drivers/md/dm-table.c | 2 +-
> drivers/mmc/core/block.c | 2 +-
> drivers/s390/block/dasd_ioctl.c | 8 ++++----
> fs/nfsd/blocklayout.c | 4 ++--
> include/linux/blkdev.h | 9 +++++++--
> kernel/trace/blktrace.c | 2 +-
> 10 files changed, 22 insertions(+), 17 deletions(-)
>
> diff --git a/block/blk-lib.c b/block/blk-lib.c
> index 0d1811e57ac704..e90614fd8d6a42 100644
> --- a/block/blk-lib.c
> +++ b/block/blk-lib.c
> @@ -64,7 +64,7 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
> return -EINVAL;
>
> /* In case the discard request is in a partition */
> - if (bdev->bd_partno)
> + if (bdev_is_partition(bdev))
> part_offset = bdev->bd_part->start_sect;
>
> while (nr_sects) {
> diff --git a/block/ioctl.c b/block/ioctl.c
> index bdb3bbb253d9f8..e4af3df9d28a68 100644
> --- a/block/ioctl.c
> +++ b/block/ioctl.c
> @@ -23,7 +23,7 @@ static int blkpg_do_ioctl(struct block_device *bdev,
> return -EACCES;
> if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
> return -EFAULT;
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> return -EINVAL;
>
> if (p.pno <= 0)
> @@ -94,7 +94,7 @@ static int blkdev_reread_part(struct block_device *bdev)
> {
> int ret;
>
> - if (!disk_part_scan_enabled(bdev->bd_disk) || bdev != bdev->bd_contains)
> + if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
> return -EINVAL;
> if (!capable(CAP_SYS_ADMIN))
> return -EACCES;
> diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
> index ef722f04f88a93..3bb4571385ce21 100644
> --- a/block/scsi_ioctl.c
> +++ b/block/scsi_ioctl.c
> @@ -854,7 +854,7 @@ EXPORT_SYMBOL(scsi_cmd_ioctl);
>
> int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
> {
> - if (bd && bd == bd->bd_contains)
> + if (bd && !bdev_is_partition(bd))
> return 0;
>
> if (capable(CAP_SYS_RAWIO))
> diff --git a/drivers/ide/ide-ioctls.c b/drivers/ide/ide-ioctls.c
> index 09491098047bff..58994da10c0664 100644
> --- a/drivers/ide/ide-ioctls.c
> +++ b/drivers/ide/ide-ioctls.c
> @@ -49,7 +49,7 @@ int ide_setting_ioctl(ide_drive_t *drive, struct block_device *bdev,
> return err >= 0 ? put_user_long(err, arg) : err;
>
> set_val:
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> err = -EINVAL;
> else {
> if (!capable(CAP_SYS_ADMIN))
> @@ -257,7 +257,7 @@ int generic_ide_ioctl(ide_drive_t *drive, struct block_device *bdev,
> switch (cmd) {
> case HDIO_OBSOLETE_IDENTITY:
> case HDIO_GET_IDENTITY:
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> return -EINVAL;
> return ide_get_identity_ioctl(drive, cmd, argp);
> case HDIO_GET_NICE:
> diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
> index 5edc3079e7c199..af156256e511ff 100644
> --- a/drivers/md/dm-table.c
> +++ b/drivers/md/dm-table.c
> @@ -903,7 +903,7 @@ static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev,
> struct request_queue *q = bdev_get_queue(bdev);
>
> /* request-based cannot stack on partitions! */
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> return false;
>
> return queue_is_mq(q);
> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> index fa313b63413547..8d3df0be0355ce 100644
> --- a/drivers/mmc/core/block.c
> +++ b/drivers/mmc/core/block.c
> @@ -723,7 +723,7 @@ static int mmc_blk_check_blkdev(struct block_device *bdev)
> * whole block device, not on a partition. This prevents overspray
> * between sibling partitions.
> */
> - if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
> + if (!capable(CAP_SYS_RAWIO) || bdev_is_partition(bdev))
> return -EPERM;
> return 0;
> }
> diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
> index faaf5596e31c12..cb6427fb9f3d16 100644
> --- a/drivers/s390/block/dasd_ioctl.c
> +++ b/drivers/s390/block/dasd_ioctl.c
> @@ -277,7 +277,7 @@ dasd_ioctl_format(struct block_device *bdev, void __user *argp)
> dasd_put_device(base);
> return -EFAULT;
> }
> - if (bdev != bdev->bd_contains) {
> + if (bdev_is_partition(bdev)) {
> pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
> dev_name(&base->cdev->dev));
> dasd_put_device(base);
> @@ -304,7 +304,7 @@ static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
> base = dasd_device_from_gendisk(bdev->bd_disk);
> if (!base)
> return -ENODEV;
> - if (bdev != bdev->bd_contains) {
> + if (bdev_is_partition(bdev)) {
> pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
> dev_name(&base->cdev->dev));
> rc = -EINVAL;
> @@ -362,7 +362,7 @@ static int dasd_ioctl_release_space(struct block_device *bdev, void __user *argp
> rc = -EROFS;
> goto out_err;
> }
> - if (bdev != bdev->bd_contains) {
> + if (bdev_is_partition(bdev)) {
> pr_warn("%s: The specified DASD is a partition and tracks cannot be released\n",
> dev_name(&base->cdev->dev));
> rc = -EINVAL;
> @@ -540,7 +540,7 @@ dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
>
> if (!capable(CAP_SYS_ADMIN))
> return -EACCES;
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> // ro setting is not allowed for partitions
> return -EINVAL;
> if (get_user(intval, (int __user *)argp))
> diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
> index 311e5ce80cfc27..a07c39c94bbd03 100644
> --- a/fs/nfsd/blocklayout.c
> +++ b/fs/nfsd/blocklayout.c
> @@ -170,7 +170,7 @@ nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
> struct nfs4_client *clp,
> struct nfsd4_getdeviceinfo *gdp)
> {
> - if (sb->s_bdev != sb->s_bdev->bd_contains)
> + if (bdev_is_partition(sb->s_bdev))
> return nfserr_inval;
> return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
> }
> @@ -382,7 +382,7 @@ nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
> struct nfs4_client *clp,
> struct nfsd4_getdeviceinfo *gdp)
> {
> - if (sb->s_bdev != sb->s_bdev->bd_contains)
> + if (bdev_is_partition(sb->s_bdev))
> return nfserr_inval;
> return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
> }
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index 7575fa0aae6e5c..0006a78ebc5dde 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -1341,6 +1341,11 @@ static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
>
> extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
>
> +static inline bool bdev_is_partition(struct block_device *bdev)
> +{
> + return bdev->bd_partno;
> +}
> +
> enum blk_default_limits {
> BLK_MAX_SEGMENTS = 128,
> BLK_SAFE_MAX_SECTORS = 255,
> @@ -1457,7 +1462,7 @@ static inline int bdev_alignment_offset(struct block_device *bdev)
>
> if (q->limits.misaligned)
> return -1;
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> return queue_limit_alignment_offset(&q->limits,
> bdev->bd_part->start_sect);
> return q->limits.alignment_offset;
> @@ -1498,7 +1503,7 @@ static inline int bdev_discard_alignment(struct block_device *bdev)
> {
> struct request_queue *q = bdev_get_queue(bdev);
>
> - if (bdev != bdev->bd_contains)
> + if (bdev_is_partition(bdev))
> return queue_limit_discard_alignment(&q->limits,
> bdev->bd_part->start_sect);
> return q->limits.discard_alignment;
> diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
> index 4b3a42fc3b24f1..157758a88773b9 100644
> --- a/kernel/trace/blktrace.c
> +++ b/kernel/trace/blktrace.c
> @@ -527,7 +527,7 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
> * and scsi-generic block devices we create a temporary new debugfs
> * directory that will be removed once the trace ends.
> */
> - if (bdev && bdev == bdev->bd_contains)
> + if (bdev && !bdev_is_partition(bdev))
> dir = q->debugfs_dir;
> else
> bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);
> --
> 2.28.0
>

2020-09-03 08:27:13

by Christoph Hellwig

[permalink] [raw]

Subject: Re: [PATCH 2/9] block: add a bdev_is_partition helper

On Thu, Sep 03, 2020 at 10:19:34AM +0200, Ulf Hansson wrote:
> On Thu, 3 Sep 2020 at 07:42, Christoph Hellwig <[email protected]> wrote:
> >
> > Add a littler helper to make the somewhat arcane bd_contains checks a
> > little more obvious.
> >
> > Signed-off-by: Christoph Hellwig <[email protected]>
>
> Not sure why we have both "bd_contains" and "bd_partno", nevertheless,
> feel free to add:

Right now both are needed for how blkdev_get/put work. But I plan to
eventual kill off bd_contains after some major surgery to that code.

2020-09-09 00:56:43

by Song Liu

[permalink] [raw]

Subject: Re: [PATCH 3/9] md: compare bd_disk instead of bd_contains

On Wed, Sep 2, 2020 at 10:43 PM Christoph Hellwig <[email protected]> wrote:
>
> To check for partitions of the same disk bd_contains works as well, but
> bd_disk is way more obvious.
>
> Signed-off-by: Christoph Hellwig <[email protected]>

Acked-by: Song Liu <[email protected]>

> ---
> drivers/md/md.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index 9562ef598ae1f4..3f33562d10d6f5 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -2322,8 +2322,7 @@ static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
> test_bit(Journal, &rdev2->flags) ||
> rdev2->raid_disk == -1)
> continue;
> - if (rdev->bdev->bd_contains ==
> - rdev2->bdev->bd_contains) {
> + if (rdev->bdev->bd_disk == rdev2->bdev->bd_disk) {
> rcu_read_unlock();
> return 1;
> }
> @@ -5944,8 +5943,8 @@ int md_run(struct mddev *mddev)
> rdev_for_each(rdev, mddev)
> rdev_for_each(rdev2, mddev) {
> if (rdev < rdev2 &&
> - rdev->bdev->bd_contains ==
> - rdev2->bdev->bd_contains) {
> + rdev->bdev->bd_disk ==
> + rdev2->bdev->bd_disk) {
> pr_warn("%s: WARNING: %s appears to be on the same physical disk as %s.\n",
> mdname(mddev),
> bdevname(rdev->bdev,b),
> --
> 2.28.0
>

2020-09-09 00:57:07

by Song Liu

[permalink] [raw]

Subject: Re: [PATCH 4/9] md: don't detour through bd_contains for the gendisk

On Wed, Sep 2, 2020 at 10:43 PM Christoph Hellwig <[email protected]> wrote:
>
> bd_disk is set on all block devices, including those for partitions.
>
> Signed-off-by: Christoph Hellwig <[email protected]>

Acked-by: Song Liu <[email protected]>

> ---
> drivers/md/md.c | 2 +-
> drivers/md/md.h | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index 3f33562d10d6f5..5a0fd93769a70e 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -8444,7 +8444,7 @@ static int is_mddev_idle(struct mddev *mddev, int init)
> idle = 1;
> rcu_read_lock();
> rdev_for_each_rcu(rdev, mddev) {
> - struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
> + struct gendisk *disk = rdev->bdev->bd_disk;
> curr_events = (int)part_stat_read_accum(&disk->part0, sectors) -
> atomic_read(&disk->sync_io);
> /* sync IO will cause sync_io to increase before the disk_stats
> diff --git a/drivers/md/md.h b/drivers/md/md.h
> index f9e2ccdd22c478..2175a5ac4f7c68 100644
> --- a/drivers/md/md.h
> +++ b/drivers/md/md.h
> @@ -551,7 +551,7 @@ extern void mddev_unlock(struct mddev *mddev);
>
> static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
> {
> - atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
> + atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
> }
>
> static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
> --
> 2.28.0
>

2020-09-15 05:46:34

by Christoph Hellwig

[permalink] [raw]

Subject: Re: clean up is partition checks

Jens,

can you pick this series up?

2020-09-25 14:20:39

by Jens Axboe

[permalink] [raw]

Subject: Re: clean up is partition checks

On 9/2/20 11:40 PM, Christoph Hellwig wrote:
> Hi Jens,
>
> this series add a new helepr to check if a struct block_device represents
> a parition, and removes most direct access to ->bd_contained from
> drivers.

Applied, thanks.

--
Jens Axboe