linux-toradex.git/drivers/block/aoe/aoeblk.c, branch v4.9.128

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

2016-04-04T17:41:08+00:00

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 -  << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 -  >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov 
Acked-by: Michal Hocko 
Signed-off-by: Linus Torvalds

Revert "block: remove artifical max_hw_sectors cap"

2015-08-18T20:21:13+00:00

This reverts commit 34b48db66e08ca1c1bc07cf305d672ac940268dc.
That commit caused performance regressions for streaming I/O
workloads on a number of different storage devices, from
SATA disks to external RAID arrays.  It also managed to
trip up some buggy firmware in at least one drive, causing
data corruption.

The next patch will bump the default max_sectors_kb value to
1280, which will accommodate a 10-data-disk stripe write
with chunk size 128k.  In the testing I've done using iozone,
fio, and aio-stress, a value of 1280 does not show a big
performance difference from 512.  This will hopefully still
help the software RAID setup that Christoph saw the original
performance gains with while still not regressing other
storage configurations.

Signed-off-by: Jeff Moyer 
Signed-off-by: Jens Axboe

block: remove artifical max_hw_sectors cap

2014-10-21T20:02:54+00:00

Set max_sectors to the value the drivers provides as hardware limit by
default.  Linux had proper I/O throttling for a long time and doesn't
rely on a artifically small maximum I/O size anymore.  By not limiting
the I/O size by default we remove an annoying tuning step required for
most Linux installation.

Note that both the user, and if absolutely required the driver can still
impose a limit for FS requests below max_hw_sectors_kb.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

aoe: do not BUG if memory pressure prevented debugfs file creation

2013-09-11T22:59:28+00:00

If the system has trouble allocating memory for the creation of the aoe
debugfs directory or of a file inside it, the debugfs member of an aoedev
can be NULL.

Do not treat a NULL debugfs pointer as a BUG on aoedev shutdown, avoiding
the user impact of an unecessary panic.

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aoe: update copyright date

2013-09-11T22:59:25+00:00

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aoe: fill in per-AoE-target information for debugfs file

2013-09-11T22:59:25+00:00

This information is presented in a compact format that has evolved for
easy routine scanning by expert humans, mostly developers and support
technicians helping to troubleshoot or test AoE-based systems.

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aoe: provide file operations for debugfs files

2013-09-11T22:59:24+00:00

The place holder in the file contents is filled out in the following
patch.

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aoe: add AoE-target files to debugfs

2013-09-11T22:59:23+00:00

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aoe: create and destroy debugfs directory for aoe

2013-09-11T22:59:22+00:00

This series adds the debugging information that the coraid.com-distributed
aoe driver exports via sysfs, but instead of sysfs, it uses debugfs.

With these patches applied, even without AoE targets on the network, KEDR
reports new possible memory leaks, but these are from callers outside the
aoe driver that have used aoe_devnode to get the name of the character
devices through the aoe_class->devnode callback, and I believe they're
responsible for freeing that memory.

This patch:

Create and destroy the debugfs directory.

Signed-off-by: Ed Cashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

block_device_operations->release() should return void

2013-05-07T06:16:21+00:00

The value passed is 0 in all but "it can never happen" cases (and those
only in a couple of drivers) *and* it would've been lost on the way
out anyway, even if something tried to pass something meaningful.
Just don't bother.

Signed-off-by: Al Viro