Commit Graph

56 Commits

Author SHA1 Message Date
Mikulas Patocka
1e1132ea21 dm writecache: fix a crash due to reading past end of dirty_bitmap
wc->dirty_bitmap_size is in bytes so must multiply it by 8, not by
BITS_PER_LONG, to get number of bitmap_bits.

Fixes crash in find_next_bit() that was reported:
https://bugzilla.kernel.org/show_bug.cgi?id=200819

Reported-by: edo.rus@gmail.com
Fixes: 48debafe4f ("dm: add writecache target")
Cc: stable@vger.kernel.org # 4.18
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-08-16 13:43:01 -04:00
Huaisheng Ye
f742267ae9 md/dm-writecache: Don't request pointer dummy_addr when not required
Function persistent_memory_claim doesn't need to get local pointer
dummy_addr from direct_access. Using NULL instead of having to pass
in a useless local pointer that caller then just throw away.

Suggested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2018-07-30 09:40:04 -07:00
Mikulas Patocka
9ff07e7d63 dm writecache: report start_sector in status line
Fixes: d284f8248c ("dm writecache: support optional offset for start of device")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-07-27 15:28:58 -04:00
Mikulas Patocka
d284f8248c dm writecache: support optional offset for start of device
Add an optional parameter "start_sector" to allow the start of the
device to be offset by the specified number of 512-byte sectors.  The
sectors below this offset are not used by the writecache device and are
left to be used for disk labels and/or userspace metadata (e.g. lvm).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-07-02 16:14:02 -04:00
Kees Cook
50a7d3ba7c dm writecache: use 2-factor allocator arguments
This adjusts the allocator calls to use the 2-factor argument style, as
already done treewide for better defense against allocator overflows.

Signed-off-by: Kees Cook <keescook@chromium.org>
[snitzer: tweaked code to leave assignment in a test alone]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-06-22 14:51:12 -04:00
Mikulas Patocka
48debafe4f dm: add writecache target
The writecache target caches writes on persistent memory or SSD.
It is intended for databases or other programs that need extremely low
commit latency.

The writecache target doesn't cache reads because reads are supposed to
be cached in page cache in normal RAM.

If persistent memory isn't available this target can still be used in
SSD mode.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com> # fix missing goto
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> # fix compilation issue with !DAX
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> # use msecs_to_jiffies
Acked-by: Dan Williams <dan.j.williams@intel.com> # reworks to unify ARM and x86 flushing
Signed-off-by: Mike Snitzer <msnitzer@redhat.com>
2018-06-08 11:59:51 -04:00