Commit Graph

60 Commits

Author SHA1 Message Date
Geert Uytterhoeven
6e85318521 lib/scatterlist: fix sg_copy_buffer() kerneldoc
Add the missing closing parenthesis to the description for the to_buffer
parameter of sg_copy_buffer().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com
Link: http://lkml.kernel.org/r/20200212084241.8778-1-geert+renesas@glider.be
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:43 -07:00
Nathan Chancellor
4e456fee21 lib/scatterlist.c: adjust indentation in __sg_alloc_table
Clang warns:

  ../lib/scatterlist.c:314:5: warning: misleading indentation; statement
  is not part of the previous 'if' [-Wmisleading-indentation]
                          return -ENOMEM;
                          ^
  ../lib/scatterlist.c:311:4: note: previous statement is here
                          if (prv)
                          ^
  1 warning generated.

This warning occurs because there is a space before the tab on this
line.  Remove it so that the indentation is consistent with the Linux
kernel coding style and clang no longer warns.

Link: http://lkml.kernel.org/r/20191218033606.11942-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/830
Fixes: edce6820a9 ("scatterlist: prevent invalid free when alloc fails")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:40 -08:00
Linus Torvalds
1f7563f743 SCSI sg on 20190709
This topic branch covers a fundamental change in how our sg lists are
 allocated to make mq more efficient by reducing the size of the
 preallocated sg list.  This necessitates a large number of driver
 changes because the previous guarantee that if a driver specified
 SG_ALL as the size of its scatter list, it would get a non-chained
 list and didn't need to bother with scatterlist iterators is now
 broken and every driver *must* use scatterlist iterators.
 
 This was broken out as a separate topic because we need to convert all
 the drivers before pulling the trigger and unconverted drivers kept
 being found, necessitating a rebase.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI scatter-gather list updates from James Bottomley:
 "This topic branch covers a fundamental change in how our sg lists are
  allocated to make mq more efficient by reducing the size of the
  preallocated sg list.

  This necessitates a large number of driver changes because the
  previous guarantee that if a driver specified SG_ALL as the size of
  its scatter list, it would get a non-chained list and didn't need to
  bother with scatterlist iterators is now broken and every driver
  *must* use scatterlist iterators.

  This was broken out as a separate topic because we need to convert all
  the drivers before pulling the trigger and unconverted drivers kept
  being found, necessitating a rebase"

* tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
  scsi: core: don't preallocate small SGL in case of NO_SG_CHAIN
  scsi: lib/sg_pool.c: clear 'first_chunk' in case of no preallocation
  scsi: core: avoid preallocating big SGL for data
  scsi: core: avoid preallocating big SGL for protection information
  scsi: lib/sg_pool.c: improve APIs for allocating sg pool
  scsi: esp: use sg helper to iterate over scatterlist
  scsi: NCR5380: use sg helper to iterate over scatterlist
  scsi: wd33c93: use sg helper to iterate over scatterlist
  scsi: ppa: use sg helper to iterate over scatterlist
  scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist
  scsi: imm: use sg helper to iterate over scatterlist
  scsi: aha152x: use sg helper to iterate over scatterlist
  scsi: s390: zfcp_fc: use sg helper to iterate over scatterlist
  scsi: staging: unisys: visorhba: use sg helper to iterate over scatterlist
  scsi: usb: image: microtek: use sg helper to iterate over scatterlist
  scsi: pmcraid: use sg helper to iterate over scatterlist
  scsi: ipr: use sg helper to iterate over scatterlist
  scsi: mvumi: use sg helper to iterate over scatterlist
  scsi: lpfc: use sg helper to iterate over scatterlist
  scsi: advansys: use sg helper to iterate over scatterlist
  ...
2019-07-11 15:17:41 -07:00
Linus Torvalds
4d2fa8b44b Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "Here is the crypto update for 5.3:

  API:
   - Test shash interface directly in testmgr
   - cra_driver_name is now mandatory

  Algorithms:
   - Replace arc4 crypto_cipher with library helper
   - Implement 5 way interleave for ECB, CBC and CTR on arm64
   - Add xxhash
   - Add continuous self-test on noise source to drbg
   - Update jitter RNG

  Drivers:
   - Add support for SHA204A random number generator
   - Add support for 7211 in iproc-rng200
   - Fix fuzz test failures in inside-secure
   - Fix fuzz test failures in talitos
   - Fix fuzz test failures in qat"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits)
  crypto: stm32/hash - remove interruptible condition for dma
  crypto: stm32/hash - Fix hmac issue more than 256 bytes
  crypto: stm32/crc32 - rename driver file
  crypto: amcc - remove memset after dma_alloc_coherent
  crypto: ccp - Switch to SPDX license identifiers
  crypto: ccp - Validate the the error value used to index error messages
  crypto: doc - Fix formatting of new crypto engine content
  crypto: doc - Add parameter documentation
  crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR
  crypto: arm64/aes-ce - add 5 way interleave routines
  crypto: talitos - drop icv_ool
  crypto: talitos - fix hash on SEC1.
  crypto: talitos - move struct talitos_edesc into talitos.h
  lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
  crypto/NX: Set receive window credits to max number of CRBs in RxFIFO
  crypto: asymmetric_keys - select CRYPTO_HASH where needed
  crypto: serpent - mark __serpent_setkey_sbox noinline
  crypto: testmgr - dynamically allocate crypto_shash
  crypto: testmgr - dynamically allocate testvec_config
  crypto: talitos - eliminate unneeded 'done' functions at build time
  ...
2019-07-08 20:57:08 -07:00
Christophe Leroy
aeb8724653 lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
All mapping iterator logic is based on the assumption that sg->offset
is always lower than PAGE_SIZE.

But there are situations where sg->offset is such that the SG item
is on the second page. In that case sg_copy_to_buffer() fails
properly copying the data into the buffer. One of the reason is
that the data will be outside the kmapped area used to access that
data.

This patch fixes the issue by adjusting the mapping iterator
offset and pgoffset fields such that offset is always lower than
PAGE_SIZE.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 4225fc8555 ("lib/scatterlist: use page iterator in the mapping iterator")
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-03 22:13:11 +08:00
Ming Lei
4635873c56 scsi: lib/sg_pool.c: improve APIs for allocating sg pool
sg_alloc_table_chained() currently allows the caller to provide one
preallocated SGL and returns if the requested number isn't bigger than
size of that SGL. This is used to inline an SGL for an IO request.

However, scattergather code only allows that size of the 1st preallocated
SGL to be SG_CHUNK_SIZE(128). This means a substantial amount of memory
(4KB) is claimed for the SGL for each IO request. If the I/O is small, it
would be prudent to allocate a smaller SGL.

Introduce an extra parameter to sg_alloc_table_chained() and
sg_free_table_chained() for specifying size of the preallocated SGL.

Both __sg_free_table() and __sg_alloc_table() assume that each SGL has the
same size except for the last one.  Change the code to allow both functions
to accept a variable size for the 1st preallocated SGL.

[mkp: attempted to clarify commit desc]

Cc: Christoph Hellwig <hch@lst.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Ewan D. Milne <emilne@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: netdev@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-06-20 15:21:33 -04:00
Thomas Gleixner
40b0b3f8fb treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
Based on 2 normalized pattern(s):

  this source code is licensed under the gnu general public license
  version 2 see the file copying for more details

  this source code is licensed under general public license version 2
  see

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 52 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:06 +02:00
Jason Gunthorpe
d901b2760d lib/scatterlist: Provide a DMA page iterator
Commit 2db76d7c3c ("lib/scatterlist: sg_page_iter: support sg lists w/o
backing pages") introduced the sg_page_iter_dma_address() function without
providing a way to use it in the general case. If the sg_dma_len() is not
equal to the sg length callers cannot safely use the
for_each_sg_page/sg_page_iter_dma_address combination.

Resolve this API mistake by providing a DMA specific iterator,
for_each_sg_dma_page(), that uses the right length so
sg_page_iter_dma_address() works as expected with all sglists.

A new iterator type is introduced to provide compile-time safety against
wrongly mixing accessors and iterators.

Acked-by: Christoph Hellwig <hch@lst.de> (for scatterlist)
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> (ipu3-cio2)
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-02-11 15:02:33 -07:00
Christoph Hellwig
7c703e54cc arch: switch the default on ARCH_HAS_SG_CHAIN
These days architectures are mostly out of the business of dealing with
struct scatterlist at all, unless they have architecture specific iommu
drivers.  Replace the ARCH_HAS_SG_CHAIN symbol with a ARCH_NO_SG_CHAIN
one only enabled for architectures with horrible legacy iommu drivers
like alpha and parisc, and conditionally for arm which wants to keep it
disable for legacy platforms.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-12-06 07:04:56 -08:00
Linus Torvalds
e6e5bec43c for-linus-20180629
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Merge tag 'for-linus-20180629' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Small set of fixes for this series. Mostly just minor fixes, the only
  oddball in here is the sg change.

  The sg change came out of the stall fix for NVMe, where we added a
  mempool and limited us to a single page allocation. CONFIG_SG_DEBUG
  sort-of ruins that, since we'd need to account for that. That's
  actually a generic problem, since lots of drivers need to allocate SG
  lists. So this just removes support for CONFIG_SG_DEBUG, which I added
  back in 2007 and to my knowledge it was never useful.

  Anyway, outside of that, this pull contains:

   - clone of request with special payload fix (Bart)

   - drbd discard handling fix (Bart)

   - SATA blk-mq stall fix (me)

   - chunk size fix (Keith)

   - double free nvme rdma fix (Sagi)"

* tag 'for-linus-20180629' of git://git.kernel.dk/linux-block:
  sg: remove ->sg_magic member
  drbd: Fix drbd_request_prepare() discard handling
  blk-mq: don't queue more if we get a busy return
  block: Fix cloning of requests with a special payload
  nvme-rdma: fix possible double free of controller async event buffer
  block: Fix transfer when chunk sectors exceeds max
2018-06-30 10:47:46 -07:00
Jens Axboe
9544bc5347 sg: remove ->sg_magic member
This was introduced more than a decade ago when sg chaining was
added, but we never really caught anything with it. The scatterlist
entry size can be critical, since drivers allocate it, so remove
the magic member. Recently it's been triggering allocation stalls
and failures in NVMe.

Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-29 08:48:06 -06:00
Kees Cook
6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Prashant Bhole
f385178679 lib/scatterlist: add sg_init_marker() helper
sg_init_marker initializes sg_magic in the sg table and calls
sg_mark_end() on the last entry of the table. This can be useful to
avoid memset in sg_init_table() when scatterlist is already zeroed out

For example: when scatterlist is embedded inside other struct and that
container struct is zeroed out

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-30 22:50:15 +02:00
Bart Van Assche
8c7a8d1c4b lib/scatterlist: Fix chaining support in sgl_alloc_order()
This patch avoids that workloads with large block sizes (megabytes)
can trigger the following call stack with the ib_srpt driver (that
driver is the only driver that chains scatterlists allocated by
sgl_alloc_order()):

BUG: Bad page state in process kworker/0:1H  pfn:2423a78
page:fffffb03d08e9e00 count:-3 mapcount:0 mapping:          (null) index:0x0
flags: 0x57ffffc0000000()
raw: 0057ffffc0000000 0000000000000000 0000000000000000 fffffffdffffffff
raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000
page dumped because: nonzero _count
CPU: 0 PID: 733 Comm: kworker/0:1H Tainted: G          I      4.15.0-rc7.bart+ #1
Hardware name: HP ProLiant DL380 G7, BIOS P67 08/16/2015
Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
Call Trace:
 dump_stack+0x5c/0x83
 bad_page+0xf5/0x10f
 get_page_from_freelist+0xa46/0x11b0
 __alloc_pages_nodemask+0x103/0x290
 sgl_alloc_order+0x101/0x180
 target_alloc_sgl+0x2c/0x40 [target_core_mod]
 srpt_alloc_rw_ctxs+0x173/0x2d0 [ib_srpt]
 srpt_handle_new_iu+0x61e/0x7f0 [ib_srpt]
 __ib_process_cq+0x55/0xa0 [ib_core]
 ib_cq_poll_work+0x1b/0x60 [ib_core]
 process_one_work+0x141/0x340
 worker_thread+0x47/0x3e0
 kthread+0xf5/0x130
 ret_from_fork+0x1f/0x30

Fixes: e80a0af475 ("lib/scatterlist: Introduce sgl_alloc() and sgl_free()")
Reported-by: Laurence Oberman <loberman@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-19 12:31:03 -07:00
Bart Van Assche
e80a0af475 lib/scatterlist: Introduce sgl_alloc() and sgl_free()
Many kernel drivers contain code that allocates and frees both a
scatterlist and the pages that populate that scatterlist.
Introduce functions in lib/scatterlist.c that perform these tasks
instead of duplicating this functionality in multiple drivers.
Only include these functions in the build if CONFIG_SGL_ALLOC=y
to avoid that the kernel size increases if this functionality is
not used.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Tvrtko Ursulin
89d8589cd7 lib/scatterlist: Introduce and export __sg_alloc_table_from_pages
Drivers like i915 benefit from being able to control the maxium
size of the sg coalesced segment while building the scatter-
gather list.

Introduce and export the __sg_alloc_table_from_pages function
which will allow it that control.

v2: Reorder parameters. (Chris Wilson)
v3: Fix incomplete reordering in v2.
v4: max_segment needs to be page aligned.
v5: Rebase.
v6: Rebase.
v7: Fix spelling in commit and mention max segment size in
    __sg_alloc_table_from_pages kerneldoc. (Andrew Morton)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: linux-kernel@vger.kernel.org
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20170803091351.23594-1-tvrtko.ursulin@linux.intel.com
2017-09-07 10:48:29 +01:00
Tvrtko Ursulin
c125906b83 lib/scatterlist: Avoid potential scatterlist entry overflow
Since the scatterlist length field is an unsigned int, make
sure that sg_alloc_table_from_pages does not overflow it while
coalescing pages to a single entry.

v2: Drop reference to future use. Use UINT_MAX.
v3: max_segment must be page aligned.
v4: Do not rely on compiler to optimise out the rounddown.
    (Joonas Lahtinen)
v5: Simplified loops and use post-increments rather than
    pre-increments. Use PAGE_MASK and fix comment typo.
    (Andy Shevchenko)
v6: Commit spelling fix.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170803091312.22875-1-tvrtko.ursulin@linux.intel.com
2017-09-07 10:48:28 +01:00
Tvrtko Ursulin
c4860ad605 lib/scatterlist: Fix offset type in sg_alloc_table_from_pages
Scatterlist entries have an unsigned int for the offset so
correct the sg_alloc_table_from_pages function accordingly.

Since these are offsets withing a page, unsigned int is
wide enough.

Also converts callers which were using unsigned long locally
with the lower_32_bits annotation to make it explicitly
clear what is happening.

v2: Use offset_in_page. (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Tomasz Stanislawski <t.stanislaws@samsung.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: linux-media@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> (v1)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170731185512.20010-1-tvrtko.ursulin@linux.intel.com
2017-09-07 10:48:27 +01:00
Johannes Thumshirn
0945e56994 scatterlist: add sg_zero_buffer() helper
The sg_zero_buffer() helper is used to zero fill an area in a SG
list.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
[hch: renamed to sg_zero_buffer]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-15 14:30:14 +02:00
Gilad Ben-Yossef
d317120097 scatterlist: do not disable IRQs in sg_copy_buffer
Commit 50bed2e286 ("sg: disable interrupts inside sg_copy_buffer")
introduced disabling interrupts in sg_copy_buffer() since atomic uses of
miter required it due to use of kmap_atomic().

However, as commit 8290e2d2dc ("scatterlist: atomic sg_mapping_iter()
no longer needs disabled IRQs") acknowledges disabling interrupts is no
longer needed for calls to kmap_atomic() and therefore unneeded for
miter ops either, so remove it from sg_copy_buffer().

Link: http://lkml.kernel.org/r/1486040150-14109-3-git-send-email-gilad@benyossef.com
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <ofir.drang@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:46 -08:00
Gilad Ben-Yossef
1d5210ef70 scatterlist: reorder compound boolean expression
Test the cheaper boolean expression with no side effects first.

Link: http://lkml.kernel.org/r/1486040150-14109-2-git-send-email-gilad@benyossef.com
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <ofir.drang@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:46 -08:00
Masahiro Yamada
4ba6a2b28f scatterlist: fix a typo in comment block of sg_miter_stop()
Fix the doubled "started" and tidy up the following sentences.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-08 10:15:17 -08:00
Christoph Hellwig
10c95ed9aa scatterlist: allow limited chaining without ARCH_HAS_SG_CHAIN
There are a couple of uses of struct scatterlist that never go to
the dma_map_sg() helper and thus don't care about ARCH_HAS_SG_CHAIN
which indicates that we can map chained S/G list.

The most important one is the crypto code, which currently has
to open code a few helpers to always allow chaining.  This patch
removes a few #ifdef ARCH_HAS_SG_CHAIN statements so that we can
switch the crypto code to these common helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:12:51 -06:00
Dave Gordon
386ecb1216 drivers/scsi/scsi_debug.c: resolve sg buffer const-ness issue
do_device_access() takes a separate parameter to indicate the direction of
data transfer, which it used to use to select the appropriate function out
of sg_pcopy_{to,from}_buffer().  However these two functions now have

So this patch makes it bypass these wrappers and call the underlying
function sg_copy_buffer() directly; this has the same calling style as
do_device_access() i.e.  a separate direction-of-transfer parameter and no
pointers-to-const, so skipping the wrappers not only eliminates the
warning, it also make the code simpler :)

[akpm@linux-foundation.org: fix very broken build]
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:59 -07:00
Dave Gordon
2a1bf8f93b lib/scatterlist: mark input buffer parameters as 'const'
The 'buf' parameter of sg(p)copy_from_buffer() can and should be
const-qualified, although because of the shared implementation of
_to_buffer() and _from_buffer(), we have to cast this away internally.

This means that callers who have a 'const' buffer containing the data to
be copied to the sg-list no longer have to cast away the const-ness
themselves.  It also enables improved coverage by code analysis tools.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:59 -07:00
Dave Gordon
4dc7daf843 lib/scatterlist.c: fix kerneldoc for sg_pcopy_{to,from}_buffer()
The kerneldoc for the functions doesn't match the code; the last two
parameters (buflen, skip) have been transposed, which is confusing,
especially as they're both integral types and the compiler won't warn
about swapping them.

These functions and the kerneldoc were introduced in commit:
    df642cea lib/scatterlist: introduce sg_pcopy_from_buffer() ...
    Author: Akinobu Mita <akinobu.mita@gmail.com>
    Date:   Mon Jul 8 16:01:54 2013 -0700

    The only difference between sg_pcopy_{from,to}_buffer() and
    sg_copy_{from,to}_buffer() is an additional argument that
    specifies the number of bytes to skip the SG list before
    copying.

The functions have the extra argument at the end, but the kerneldoc
lists it in penultimate position.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:59 -07:00
Tom Lendacky
cfaed10d1f scatterlist: introduce sg_nents_for_len
When performing a dma_map_sg() call, the number of sg entries to map is
required. Using sg_nents to retrieve the number of sg entries will
return the total number of entries in the sg list up to the entry marked
as the end. If there happen to be unused entries in the list, these will
still be counted. Some dma_map_sg() implementations will not handle the
unused entries correctly (lib/swiotlb.c) and execute a BUG_ON.

The sg_nents_for_len() function will traverse the sg list and return the
number of entries required to satisfy the supplied length argument. This
can then be supplied to the dma_map_sg() call to successfully map the
sg.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-03 10:51:27 +08:00
Tony Battersby
c21e59d8dc lib/scatterlist: fix memory leak with scsi-mq
Fix a memory leak with scsi-mq triggered by commands with large data
transfer length.

Fixes: c53c6d6a68 ("scatterlist: allow chaining to preallocated chunks")
Cc: <stable@vger.kernel.org> # 3.17.x
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-28 10:27:10 -06:00
Laura Abbott
308c09f17d lib/scatterlist: make ARCH_HAS_SG_CHAIN an actual Kconfig
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an
architecture specific scatterlist.h, make it a proper Kconfig option and
use that instead.  At same time, remove the header files are are now
mostly useless and just include asm-generic/scatterlist.h.

[sfr@canb.auug.org.au: powerpc files now need asm/dma.h]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>			[x86]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>	[powerpc]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:26 -07:00
Christoph Hellwig
c53c6d6a68 scatterlist: allow chaining to preallocated chunks
Blk-mq drivers usually preallocate their S/G list as part of the request,
but if we want to support the very large S/G lists currently supported by
the SCSI code that would tie up a lot of memory in the preallocated request
pool.  Add support to the scatterlist code so that it can initialize a
S/G list that uses a preallocated first chunks and dynamically allocated
additional chunks.  That way the scsi-mq code can preallocate a first
page worth of S/G entries as part of the request, and dynamically extend
the S/G list when needed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 17:16:21 -04:00
Ming Lei
0d6077f8b4 lib/scatterlist: export sg_miter_skip()
sg_copy_buffer() can't meet demand for some drrivers(such usb
mass storage), so we have to use the sg_miter_* APIs to access
sg buffer, then need export sg_miter_skip() for these drivers.

The API is needed for converting to sg_miter_* APIs in USB storage
driver for accessing sg buffer.

Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 17:56:37 -08:00
Ming Lei
3d77b50c58 lib/scatterlist.c: don't flush_kernel_dcache_page on slab page
Commit b1adaf65ba ("[SCSI] block: add sg buffer copy helper
functions") introduces two sg buffer copy helpers, and calls
flush_kernel_dcache_page() on pages in SG list after these pages are
written to.

Unfortunately, the commit may introduce a potential bug:

 - Before sending some SCSI commands, kmalloc() buffer may be passed to
   block layper, so flush_kernel_dcache_page() can see a slab page
   finally

 - According to cachetlb.txt, flush_kernel_dcache_page() is only called
   on "a user page", which surely can't be a slab page.

 - ARCH's implementation of flush_kernel_dcache_page() may use page
   mapping information to do optimization so page_mapping() will see the
   slab page, then VM_BUG_ON() is triggered.

Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled,
and this patch fixes the bug by adding test of '!PageSlab(miter->page)'
before calling flush_kernel_dcache_page().

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Simon Baatz <gmbnomis@gmail.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>	[3.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 16:58:13 -07:00
Dan Carpenter
27daabd9b6 lib/scatterlist: error handling in __sg_alloc_table()
I was reviewing code which I suspected might allocate a zero size SG
table.  That will cause memory corruption.  Also we can't return before
doing the memset or we could end up using uninitialized memory in the
cleanup path.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:31 -07:00
Akinobu Mita
df642cea25 lib/scatterlist: introduce sg_pcopy_from_buffer() and sg_pcopy_to_buffer()
The only difference between sg_pcopy_{from,to}_buffer() and
sg_copy_{from,to}_buffer() is an additional argument that specifies the
number of bytes to skip the SG list before copying.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Imre Deak <imre.deak@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Akinobu Mita
1105200480 lib/scatterlist: factor out sg_miter_get_next_page() from sg_miter_next()
This patchset introduces sg_pcopy_from_buffer() and sg_pcopy_to_buffer(),
which copy data between a linear buffer and an SG list.

The only difference between sg_pcopy_{from,to}_buffer() and
sg_copy_{from,to}_buffer() is an additional argument that specifies the
number of bytes to skip the SG list before copying.

The main reason for introducing these functions is to fix a problem in
scsi_debug module.  And there is a local function in crypto/talitos
module, which can be replaced by sg_pcopy_to_buffer().

This patch:

sg_miter_get_next_page() is used to proceed page iterator to the next page
if necessary, and will be used to implement the variants of
sg_copy_{from,to}_buffer() later.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Imre Deak
2db76d7c3c lib/scatterlist: sg_page_iter: support sg lists w/o backing pages
The i915 driver uses sg lists for memory without backing 'struct page'
pages, similarly to other IO memory regions, setting only the DMA
address for these. It does this, so that it can program the HW MMU
tables in a uniform way both for sg lists with and without backing pages.

Without a valid page pointer we can't call nth_page to get the current
page in __sg_page_iter_next, so add a helper that relevant users can
call separately. Also add a helper to get the DMA address of the current
page (idea from Daniel).

Convert all places in i915, to use the new API.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-27 17:13:44 +01:00
Imre Deak
4225fc8555 lib/scatterlist: use page iterator in the mapping iterator
For better code reuse use the newly added page iterator to iterate
through the pages.  The offset, length within the page is still
calculated by the mapping iterator as well as the actual mapping.  Idea
from Tejun Heo.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:10 -08:00
Imre Deak
a321e91b6d lib/scatterlist: add simple page iterator
Add an iterator to walk through a scatter list a page at a time starting
at a specific page offset.  As opposed to the mapping iterator this is
meant to be small, performing well even in simple loops like collecting
all pages on the scatterlist into an array or setting up an iommu table
based on the pages' DMA address.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:10 -08:00
Nick Bowler
6fd59a83b9 scatterlist: don't BUG when we can trivially return a proper error.
There is absolutely no reason to crash the kernel when we have a
perfectly good return value already available to use for conveying
failure status.

Let's return an error code instead of crashing the kernel: that sounds
like a much better plan.

[akpm@linux-foundation.org: s/E2BIG/EINVAL/]
Signed-off-by: Nick Bowler <nbowler@elliptictech.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:28 -08:00
Linus Torvalds
ce40be7a82 Merge branch 'for-3.7/core' of git://git.kernel.dk/linux-block
Pull block IO update from Jens Axboe:
 "Core block IO bits for 3.7.  Not a huge round this time, it contains:

   - First series from Kent cleaning up and generalizing bio allocation
     and freeing.

   - WRITE_SAME support from Martin.

   - Mikulas patches to prevent O_DIRECT crashes when someone changes
     the block size of a device.

   - Make bio_split() work on data-less bio's (like trim/discards).

   - A few other minor fixups."

Fixed up silent semantic mis-merge as per Mikulas Patocka and Andrew
Morton.  It is due to the VM no longer using a prio-tree (see commit
6b2dbba8b6ac: "mm: replace vma prio_tree with an interval tree").

So make set_blocksize() use mapping_mapped() instead of open-coding the
internal VM knowledge that has changed.

* 'for-3.7/core' of git://git.kernel.dk/linux-block: (26 commits)
  block: makes bio_split support bio without data
  scatterlist: refactor the sg_nents
  scatterlist: add sg_nents
  fs: fix include/percpu-rwsem.h export error
  percpu-rw-semaphore: fix documentation typos
  fs/block_dev.c:1644:5: sparse: symbol 'blkdev_mmap' was not declared
  blockdev: turn a rw semaphore into a percpu rw semaphore
  Fix a crash when block device is read and block size is changed at the same time
  block: fix request_queue->flags initialization
  block: lift the initial queue bypass mode on blk_register_queue() instead of blk_init_allocated_queue()
  block: ioctl to zero block ranges
  block: Make blkdev_issue_zeroout use WRITE SAME
  block: Implement support for WRITE SAME
  block: Consolidate command flag and queue limit checks for merges
  block: Clean up special command handling logic
  block/blk-tag.c: Remove useless kfree
  block: remove the duplicated setting for congestion_threshold
  block: reject invalid queue attribute values
  block: Add bio_clone_bioset(), bio_clone_kmalloc()
  block: Consolidate bio_alloc_bioset(), bio_kmalloc()
  ...
2012-10-11 09:04:23 +09:00
Tejun Heo
8290e2d2dc scatterlist: atomic sg_mapping_iter() no longer needs disabled IRQs
SG mapping iterator w/ SG_MITER_ATOMIC set required IRQ disabled because
it originally used KM_BIO_SRC_IRQ to allow use from IRQ handlers.
kmap_atomic() has long been updated to handle stacking atomic mapping
requests on per-cpu basis and only requires not sleeping while mapped.

Update sg_mapping_iter such that atomic iterators only require disabling
preemption instead of disabling IRQ.

While at it, convert wte weird @ARG@ notations to @ARG in the comment of
sg_miter_start().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:04:58 +09:00
Maxim Levitsky
232f1b5106 scatterlist: refactor the sg_nents
Replace 'while' with 'for' as suggested by Tejun Heo

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-09-28 10:38:15 +02:00
Maxim Levitsky
2e48461029 scatterlist: add sg_nents
Useful helper to know the number of entries in scatterlist.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Alex Dubov <oakad@yahoo.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-09-27 12:45:28 +02:00
Linus Torvalds
27c1ee3f92 Merge branch 'akpm' (Andrew's patch-bomb)
Merge Andrew's first set of patches:
 "Non-MM patches:

   - lots of misc bits

   - tree-wide have_clk() cleanups

   - quite a lot of printk tweaks.  I draw your attention to "printk:
     convert the format for KERN_<LEVEL> to a 2 byte pattern" which
     looks a bit scary.  But afaict it's solid.

   - backlight updates

   - lib/ feature work (notably the addition and use of memweight())

   - checkpatch updates

   - rtc updates

   - nilfs updates

   - fatfs updates (partial, still waiting for acks)

   - kdump, proc, fork, IPC, sysctl, taskstats, pps, etc

   - new fault-injection feature work"

* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  drivers/misc/lkdtm.c: fix missing allocation failure check
  lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
  fault-injection: add tool to run command with failslab or fail_page_alloc
  fault-injection: add selftests for cpu and memory hotplug
  powerpc: pSeries reconfig notifier error injection module
  memory: memory notifier error injection module
  PM: PM notifier error injection module
  cpu: rewrite cpu-notifier-error-inject module
  fault-injection: notifier error injection
  c/r: fcntl: add F_GETOWNER_UIDS option
  resource: make sure requested range is included in the root range
  include/linux/aio.h: cpp->C conversions
  fs: cachefiles: add support for large files in filesystem caching
  pps: return PTR_ERR on error in device_create
  taskstats: check nla_reserve() return
  sysctl: suppress kmemleak messages
  ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
  ipc: compat: use signed size_t types for msgsnd and msgrcv
  ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
  ipc: add COMPAT_SHMLBA support
  ...
2012-07-30 17:25:34 -07:00
Mandeep Singh Baines
e04f228335 lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
We are seeing a lot of sg_alloc_table allocation failures using the new
drm prime infrastructure.  We isolated the cause to code in
__sg_alloc_table that was re-writing the gfp_flags.

There is a comment in the code that suggest that there is an assumption
about the allocation coming from a memory pool.  This was likely true
when sg lists were primarily used for disk I/O.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Rob Clark <rob.clark@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Olof Johansson <olofj@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:22 -07:00
Tomasz Stanislawski
efc42bc980 scatterlist: add sg_alloc_table_from_pages function
This patch adds a new constructor for an sg table. The table is constructed
from an array of struct pages. All contiguous chunks of the pages are merged
into a single sg nodes. A user may provide an offset and a size of a buffer if
the buffer is not page-aligned.

The function is dedicated for DMABUF exporters which often perform conversion
from an page array to a scatterlist. Moreover the scatterlist should be
squashed in order to save memory and to speed-up the process of DMA mapping
using dma_map_sg.

The code is based on the patch 'v4l: vb2-dma-contig: add support for
scatterlist in userptr mode' and hints from Laurent Pinchart.

Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
CC: Andrew Morton <akpm@linux-foundation.org>
2012-07-30 12:25:44 +02:00
Linus Torvalds
11bcb32848 The following text was taken from the original review request:
"[PATCH 0/3] RFC - module.h usage cleanups in fs/ and lib/"
 		https://lkml.org/lkml/2012/2/29/589
 --
 
 Fix up files in fs/ and lib/ dirs to only use module.h if they really
 need it.
 
 These are trivial in scope vs. the work done previously.  We now have
 things where any few remaining cleanups can be farmed out to arch or
 subsystem maintainers, and I have done so when possible.  What is
 remaining here represents the bits that don't clearly lie within a
 single arch/subsystem boundary, like the fs dir and the lib dir.
 
 Some duplicate includes arising from overlapping fixes from
 independent subsystem maintainer submissions are also quashed.
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Merge tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker:
 "Fix up files in fs/ and lib/ dirs to only use module.h if they really
  need it.

  These are trivial in scope vs the work done previously.  We now have
  things where any few remaining cleanups can be farmed out to arch or
  subsystem maintainers, and I have done so when possible.  What is
  remaining here represents the bits that don't clearly lie within a
  single arch/subsystem boundary, like the fs dir and the lib dir.

  Some duplicate includes arising from overlapping fixes from
  independent subsystem maintainer submissions are also quashed."

Fix up trivial conflicts due to clashes with other include file cleanups
(including some due to the previous bug.h cleanup pull).

* tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  lib: reduce the use of module.h wherever possible
  fs: reduce the use of module.h wherever possible
  includecheck: delete any duplicate instances of module.h
2012-03-24 10:24:31 -07:00
Cong Wang
c3eede8e0a lib: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:27 +08:00
Paul Gortmaker
8bc3bcc93a lib: reduce the use of module.h wherever possible
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-03-07 15:04:04 -05:00
Jeffrey Carlyle
edce6820a9 scatterlist: prevent invalid free when alloc fails
When alloc fails, free_table is being called. Depending on the number of
bytes requested, we determine if we are going to call _get_free_page()
or kmalloc(). When alloc fails, our math is wrong (due to sg_size - 1),
and the last buffer is wrongfully assumed to have been allocated by
kmalloc. Hence, kfree gets called and a panic occurs.

Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
Signed-off-by: Olusanya Soyannwo <c23746@motorola.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-30 19:55:09 +02:00