linux/drivers/block
Minchan Kim 2e32baea46 zram: revalidate disk after capacity change
Alexander reported mkswap on /dev/zram0 is failed if other process is
opening the block device file.

Step is as follows,

0. Reset the unused zram device.
1. Use a program that opens /dev/zram0 with O_RDWR and sleeps
   until killed.
2. While that program sleeps, echo the correct value to
   /sys/block/zram0/disksize.
3. Verify (e.g. in /proc/partitions) that the disk size is applied
   correctly. It is.
4. While that program still sleeps, attempt to mkswap /dev/zram0.
   This fails: mkswap: error: swap area needs to be at least 40 KiB

When I investigated, the size get by ioctl(fd, BLKGETSIZE64, xxx) on
mkswap to get a size of blockdev was zero although zram0 has right size by
2.

The reason is zram didn't revalidate disk after changing capacity so that
size of blockdev's inode is not uptodate until all of file is close.

This patch should fix the BUG.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Alexander E. Patrakov <patrakov@gmail.com>
Tested-by: Alexander E. Patrakov <patrakov@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-03 09:21:53 -07:00
..
aoe mm: close PageTail race 2014-03-04 07:55:47 -08:00
drbd drbd: fix NULL pointer deref in blk_add_request_payload 2014-06-25 09:53:47 -06:00
mtip32xx mtip32xx: minor performance enhancements 2014-06-06 13:28:48 -06:00
paride block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
rsxx
xen-blkback xen-blkback: defer freeing blkif to avoid blocking xenwatch 2014-05-28 14:17:32 -04:00
zram zram: revalidate disk after capacity change 2014-07-03 09:21:53 -07:00
amiflop.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
ataflop.c Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into next 2014-06-02 09:29:34 -07:00
brd.c brd: return -ENOSPC rather than -ENOMEM on page allocation failure 2014-06-04 16:54:02 -07:00
cciss_cmd.h
cciss_scsi.c
cciss_scsi.h
cciss.c cciss: Use pci_enable_msix_exact() instead of pci_enable_msix() 2014-04-21 19:02:08 -06:00
cciss.h
cpqarray.c
cpqarray.h
cryptoloop.c
DAC960.c DAC960: remove sleep_on usage 2014-03-13 14:56:38 -06:00
DAC960.h
floppy.c Merge branch 'for-jens' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/linux-block into for-linus 2014-06-18 10:30:22 -07:00
hd.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
ida_cmd.h
ida_ioctl.h
Kconfig zram: promote zram from staging 2014-01-30 16:56:55 -08:00
loop.c Merge branch 'sched/urgent' into sched/core, to avoid conflicts 2014-05-07 13:15:46 +02:00
loop.h
Makefile zram: promote zram from staging 2014-01-30 16:56:55 -08:00
mg_disk.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
nbd.c nbd: zero from and len fields in NBD_CMD_DISCONNECT. 2014-06-06 16:08:18 -07:00
null_blk.c null_blk: fix softirq completions for queue_mode == 1 2014-06-16 11:40:25 -06:00
nvme-core.c Merge git://git.infradead.org/users/willy/linux-nvme 2014-06-15 15:58:03 -10:00
nvme-scsi.c NVMe: Fix START_STOP_UNIT Scsi->NVMe translation. 2014-06-13 13:11:00 -04:00
osdblk.c
pktcdvd.c block: add blk_rq_set_block_pc() 2014-06-06 07:57:37 -06:00
ps3disk.c block: Kill bio_segments()/bi_vcnt usage 2013-11-23 22:33:51 -08:00
ps3vram.c
rbd_types.h
rbd.c rbd: handle parent_overlap on writes correctly 2014-06-23 12:55:37 +04:00
skd_main.c Merge branch 'for-3.16/core' into for-3.16/drivers 2014-05-28 09:50:26 -06:00
skd_s1120.h
smart1,2.h
sunvdc.c
swim3.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
swim_asm.S
swim.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
sx8.c drivers/block/sx8.c: remove unnecessary pci_set_drvdata() 2014-01-21 20:16:56 -08:00
umem.c block: Convert drivers to immutable biovecs 2013-11-23 22:33:51 -08:00
umem.h
virtio_blk.c Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into next 2014-06-02 09:29:34 -07:00
xen-blkfront.c Merge branch 'stable/for-jens-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip into for-3.16/drivers 2014-05-28 12:37:04 -06:00
xsysace.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
z2ram.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00