Russell King [Wed, 3 Aug 2011 23:01:00 +0000 (00:01 +0100)]
ARM: Fix build error for SMP=n builds
Unfortunately, the module fixups cause the kernel to fail to build
when SMP is not enabled. Fix this by removing the reference to
fixup_smp on non-SMP fixup kernels, but ensuring that if we do have
the SMP fixup section, we refuse to load the module.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Linus Torvalds [Thu, 4 Aug 2011 01:12:09 +0000 (15:12 -1000)]
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
tcm_fc: Handle DDP/SW fc_frame_payload_get failures in ft_recv_write_data
target: Fix bug for transport_generic_wait_for_tasks with direct operation
target: iscsi_target depends on NET
target: Fix WRITE_SAME_16 lba assignment breakage
MAINTAINERS: Add target-devel list for drivers/target/
iscsi-target: Fix CONFIG_SMP=n and CONFIG_MODULES=n build failure
iscsi-target: Fix snprintf usage with MAX_PORTAL_LEN
iscsi-target: Fix uninitialized usage of cmd->pad_bytes
iscsi-target: strlen() doesn't count the terminator
iscsi-target: Fix NULL dereference on allocation failure
Vasiliy Kulikov [Wed, 3 Aug 2011 18:28:26 +0000 (22:28 +0400)]
shm: optimize exit_shm()
We may optimistically check .in_use == 0 without holding the rw_mutex:
it's the common case, and if it's zero, there certainly won't be any
segments associated with us.
After taking the lock, the idr_for_each() will do the right thing, so we
could now drop the re-check inside the lock without any real cost. But
it won't hurt.
tmpfs: expand "help" to explain value of TMPFS_POSIX_ACL
Expand the fs/Kconfig "help" info to clarify why it's a bad idea to
deselect the TMPFS_POSIX_ACL config variable.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:28 +0000 (16:21 -0700)]
mm: clarify the radix_tree exceptional cases
Make the radix_tree exceptional cases, mostly in filemap.c, clearer.
It's hard to devise a suitable snappy name that illuminates the use by
shmem/tmpfs for swap, while keeping filemap/pagecache/radix_tree
generality. And akpm points out that /* radix_tree_deref_retry(page) */
comments look like calls that have been commented out for unknown
reason.
Skirt the naming difficulty by rearranging these blocks to handle the
transient radix_tree_deref_retry(page) case first; then just explain the
remaining shmem/tmpfs swap case in a comment.
Hugh Dickins [Wed, 3 Aug 2011 23:21:27 +0000 (16:21 -0700)]
tmpfs radix_tree: locate_item to speed up swapoff
We have already acknowledged that swapoff of a tmpfs file is slower than
it was before conversion to the generic radix_tree: a little slower
there will be acceptable, if the hotter paths are faster.
But it was a shock to find swapoff of a 500MB file 20 times slower on my
laptop, taking 10 minutes; and at that rate it significantly slows down
my testing.
Now, most of that turned out to be overhead from PROVE_LOCKING and
PROVE_RCU: without those it was only 4 times slower than before; and
more realistic tests on other machines don't fare as badly.
I've tried a number of things to improve it, including tagging the swap
entries, then doing lookup by tag: I'd expected that to halve the time,
but in practice it's erratic, and often counter-productive.
The only change I've so far found to make a consistent improvement, is
to short-circuit the way we go back and forth, gang lookup packing
entries into the array supplied, then shmem scanning that array for the
target entry. Scanning in place doubles the speed, so it's now only
twice as slow as before (or three times slower when the PROVEs are on).
So, add radix_tree_locate_item() as an expedient, once-off,
single-caller hack to do the lookup directly in place. #ifdef it on
CONFIG_SHMEM and CONFIG_SWAP, as much to document its limited
applicability as save space in other configurations. And, sadly,
#include sched.h for cond_resched().
Hugh Dickins [Wed, 3 Aug 2011 23:21:27 +0000 (16:21 -0700)]
mm: a few small updates for radix-swap
Remove PageSwapBacked (!page_is_file_cache) cases from
add_to_page_cache_locked() and add_to_page_cache_lru(): those pages now
go through shmem_add_to_page_cache().
Remove a comment on maximum tmpfs size from fsstack_copy_inode_size(),
and add a comment on swap entries to invalidate_mapping_pages().
And mincore_page() uses find_get_page() on what might be shmem or a
tmpfs file: allow for a radix_tree_exceptional_entry(), and proceed to
find_get_page() on swapper_space if so (oh, swapper_space needs #ifdef).
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:26 +0000 (16:21 -0700)]
tmpfs: use kmemdup for short symlinks
But we've not yet removed the old swp_entry_t i_direct[16] from
shmem_inode_info. That's because it was still being shared with the
inline symlink. Remove it now (saving 64 or 128 bytes from shmem inode
size), and use kmemdup() for short symlinks, say, those up to 128 bytes.
I wonder why mpol_free_shared_policy() is done in shmem_destroy_inode()
rather than shmem_evict_inode(), where we usually do such freeing? I
guess it doesn't matter, and I'm not into NUMA mpol testing right now.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:25 +0000 (16:21 -0700)]
tmpfs: convert shmem_writepage and enable swap
Convert shmem_writepage() to use shmem_delete_from_page_cache() to use
shmem_radix_tree_replace() to substitute swap entry for page pointer
atomically in the radix tree.
As with shmem_add_to_page_cache(), it's not entirely satisfactory to be
copying such code from delete_from_swap_cache, but again judged easier
to sell than making its other callers go through the extras.
Remove the toy implementation's shmem_put_swap() and shmem_get_swap(),
now unreferenced, and the hack to disable swap: it's now good to go.
The way things have worked out, info->lock no longer helps to guard the
shmem_swaplist: we increment swapped under shmem_swaplist_mutex only.
That global mutex exclusion between shmem_writepage() and shmem_unuse()
is not pretty, and we ought to find another way; but it's been forced on
us by recent race discoveries, not a consequence of this patchset.
And what has become of the WARN_ON_ONCE(1) free_swap_and_cache() if a
swap entry was found already present? That's no longer possible, the
(unknown) one inserting this page into filecache would hit the swap
entry occupying that slot.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:24 +0000 (16:21 -0700)]
tmpfs: convert mem_cgroup shmem to radix-swap
Remove mem_cgroup_shmem_charge_fallback(): it was only required when we
had to move swappage to filecache with GFP_NOWAIT.
Remove the GFP_NOWAIT special case from mem_cgroup_cache_charge(), by
moving its call out from shmem_add_to_page_cache() to two of thats three
callers. But leave it doing mem_cgroup_uncharge_cache_page() on error:
although asymmetrical, it's easier for all 3 callers to handle.
These two changes would also be appropriate if anyone were to start
using shmem_read_mapping_page_gfp() with GFP_NOWAIT.
Remove mem_cgroup_get_shmem_target(): mc_handle_file_pte() can test
radix_tree_exceptional_entry() to get what it needs for itself.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:24 +0000 (16:21 -0700)]
tmpfs: convert shmem_getpage_gfp to radix-swap
Convert shmem_getpage_gfp(), the engine-room of shmem, to expect page or
swap entry returned from radix tree by find_lock_page().
Whereas the repetitive old method proceeded mainly under info->lock,
dropping and repeating whenever one of the conditions needed was not
met, now we can proceed without it, leaving shmem_add_to_page_cache() to
check for a race.
This way there is no need to preallocate a page, no need for an early
radix_tree_preload(), no need for mem_cgroup_shmem_charge_fallback().
Move the error unwinding down to the bottom instead of repeating it
throughout. ENOSPC handling is a little different from before: there is
no longer any race between find_lock_page() and finding swap, but we can
arrive at ENOSPC before calling shmem_recalc_inode(), which might
occasionally discover freed space.
Be stricter to check i_size before returning. info->lock is used for
little but alloced, swapped, i_blocks updates. Move i_blocks updates
out from under the max_blocks check, so even an unlimited size=0 mount
can show accurate du.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:23 +0000 (16:21 -0700)]
tmpfs: convert shmem_unuse_inode to radix-swap
Convert shmem_unuse_inode() to use a lockless gang lookup of the radix
tree, searching for matching swap.
This is somewhat slower than the old method: because of repeated radix
tree descents, because of copying entries up, but probably most because
the old method noted and skipped once a vector page was cleared of swap.
Perhaps we can devise a use of radix tree tagging to achieve that later.
shmem_add_to_page_cache() uses shmem_radix_tree_replace() to compensate
for the lockless lookup by checking that the expected entry is in place,
under lock. It is not very satisfactory to be copying this much from
add_to_page_cache_locked(), but I think easier to sell than insisting
that every caller of add_to_page_cache*() go through the extras.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:22 +0000 (16:21 -0700)]
tmpfs: convert shmem_truncate_range to radix-swap
Disable the toy swapping implementation in shmem_writepage() - it's hard
to support two schemes at once - and convert shmem_truncate_range() to a
lockless gang lookup of swap entries along with pages, freeing both.
Since the second loop tightens its noose until all entries of either
kind have been squeezed out (and we shall make sure that there's not an
instant when neither is visible), there is no longer a need for yet
another pass below.
shmem_radix_tree_replace() compensates for the lockless lookup by
checking that the expected entry is in place, under lock, before
replacing it. Here it just deletes, but will be used in later patches
to substitute swap entry for page or page for swap entry.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:21 +0000 (16:21 -0700)]
tmpfs: copy truncate_inode_pages_range
Bring truncate.c's code for truncate_inode_pages_range() inline into
shmem_truncate_range(), replacing its first call (there's a followup
call below, but leave that one, it will disappear next).
Don't play with it yet, apart from leaving out the cleancache flush, and
(importantly) the nrpages == 0 skip, and moving shmem_setattr()'s
partial page preparation into its partial page handling.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:21 +0000 (16:21 -0700)]
tmpfs: miscellaneous trivial cleanups
While it's at its least, make a number of boring nitpicky cleanups to
shmem.c, mostly for consistency of variable naming. Things like "swap"
instead of "entry", "pgoff_t index" instead of "unsigned long idx".
And since everything else here is prefixed "shmem_", better change
init_tmpfs() to shmem_init().
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:20 +0000 (16:21 -0700)]
tmpfs: demolish old swap vector support
The maximum size of a shmem/tmpfs file has been limited by the maximum
size of its triple-indirect swap vector. With 4kB page size, maximum
filesize was just over 2TB on a 32-bit kernel, but sadly one eighth of
that on a 64-bit kernel. (With 8kB page size, maximum filesize was just
over 4TB on a 64-bit kernel, but 16TB on a 32-bit kernel,
MAX_LFS_FILESIZE being then more restrictive than swap vector layout.)
It's a shame that tmpfs should be more restrictive than ramfs, and this
limitation has now been noticed. Add another level to the swap vector?
No, it became obscure and hard to maintain, once I complicated it to
make use of highmem pages nine years ago: better choose another way.
Surely, if 2.4 had had the radix tree pagecache introduced in 2.5, then
tmpfs would never have invented its own peculiar radix tree: we would
have fitted swap entries into the common radix tree instead, in much the
same way as we fit swap entries into page tables.
And why should each file have a separate radix tree for its pages and
for its swap entries? The swap entries are required precisely where and
when the pages are not. We want to put them together in a single radix
tree: which can then avoid much of the locking which was needed to
prevent them from being exchanged underneath us.
This also avoids the waste of memory devoted to swap vectors, first in
the shmem_inode itself, then at least two more pages once a file grew
beyond 16 data pages (pages accounted by df and du, but not by memcg).
Allocated upfront, to avoid allocation when under swapping pressure, but
pure waste when CONFIG_SWAP is not set - I have never spattered around
the ifdefs to prevent that, preferring this move to sharing the common
radix tree instead.
There are three downsides to sharing the radix tree. One, that it binds
tmpfs more tightly to the rest of mm, either requiring knowledge of swap
entries in radix tree there, or duplication of its code here in shmem.c.
I believe that the simplications and memory savings (and probable higher
performance, not yet measured) justify that.
Two, that on HIGHMEM systems with SWAP enabled, it's the lowmem radix
nodes that cannot be freed under memory pressure - whereas before it was
the less precious highmem swap vector pages that could not be freed.
I'm hoping that 64-bit has now been accessible for long enough, that the
highmem argument has grown much less persuasive.
Three, that swapoff is slower than it used to be on tmpfs files, since
it's using a simple generic mechanism not tailored to it: I find this
noticeable, and shall want to improve, but maybe nobody else will
notice.
So... now remove most of the old swap vector code from shmem.c. But,
for the moment, keep the simple i_direct vector of 16 pages, with simple
accessors shmem_put_swap() and shmem_get_swap(), as a toy implementation
to help mark where swap needs to be handled in subsequent patches.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:19 +0000 (16:21 -0700)]
mm: let swap use exceptional entries
If swap entries are to be stored along with struct page pointers in a
radix tree, they need to be distinguished as exceptional entries.
Most of the handling of swap entries in radix tree will be contained in
shmem.c, but a few functions in filemap.c's common code need to check
for their appearance: find_get_page(), find_lock_page(),
find_get_pages() and find_get_pages_contig().
So as not to slow their fast paths, tuck those checks inside the
existing checks for unlikely radix_tree_deref_slot(); except for
find_lock_page(), where it is an added test. And make it a BUG in
find_get_pages_tag(), which is not applied to tmpfs files.
A part of the reason for eliminating shmem_readpage() earlier, was to
minimize the places where common code would need to allow for swap
entries.
The swp_entry_t known to swapfile.c must be massaged into a slightly
different form when stored in the radix tree, just as it gets massaged
into a pte_t when stored in page tables.
In an i386 kernel this limits its information (type and page offset) to
30 bits: given 32 "types" of swapfile and 4kB pagesize, that's a maximum
swapfile size of 128GB. Which is less than the 512GB we previously
allowed with X86_PAE (where the swap entry can occupy the entire upper
32 bits of a pte_t), but not a new limitation on 32-bit without PAE; and
there's not a new limitation on 64-bit (where swap filesize is already
limited to 16TB by a 32-bit page offset). Thirty areas of 128GB is
probably still enough swap for a 64GB 32-bit machine.
Provide swp_to_radix_entry() and radix_to_swp_entry() conversions, and
enforce filesize limit in read_swap_header(), just as for ptes.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Wed, 3 Aug 2011 23:21:18 +0000 (16:21 -0700)]
radix_tree: exceptional entries and indices
A patchset to extend tmpfs to MAX_LFS_FILESIZE by abandoning its
peculiar swap vector, instead keeping a file's swap entries in the same
radix tree as its struct page pointers: thus saving memory, and
simplifying its code and locking.
This patch:
The radix_tree is used by several subsystems for different purposes. A
major use is to store the struct page pointers of a file's pagecache for
memory management. But what if mm wanted to store something other than
page pointers there too?
The low bit of a radix_tree entry is already used to denote an indirect
pointer, for internal use, and the unlikely radix_tree_deref_retry()
case.
Define the next bit as denoting an exceptional entry, and supply inline
functions radix_tree_exception() to return non-0 in either unlikely
case, and radix_tree_exceptional_entry() to return non-0 in the second
case.
If a subsystem already uses radix_tree with that bit set, no problem: it
does not affect internal workings at all, but is defined for the
convenience of those storing well-aligned pointers in the radix_tree.
The radix_tree_gang_lookups have an implicit assumption that the caller
can deduce the offset of each entry returned e.g. by the page->index of
a struct page. But that may not be feasible for some kinds of item to
be stored there.
radix_tree_gang_lookup_slot() allow for an optional indices argument,
output array in which to return those offsets. The same could be added
to other radix_tree_gang_lookups, but for now keep it to the only one
for which we need it.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Wed, 3 Aug 2011 23:21:17 +0000 (16:21 -0700)]
drivers/video/backlight/aat2870_bl.c: make it buildable as a module
i386 allmodconfig:
drivers/built-in.o: In function `aat2870_bl_remove':
aat2870_bl.c:(.text+0x414f9): undefined reference to `backlight_device_unregister'
drivers/built-in.o: In function `aat2870_bl_probe':
aat2870_bl.c:(.text+0x418fc): undefined reference to `backlight_device_register'
aat2870_bl.c:(.text+0x41a31): undefined reference to `backlight_device_unregiste
Cc: Jin Park <jinyoungp@nvidia.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Current implementation tests wrong value for setting
aat2870_bl->max_current.
- In the current implementation, we cannot differentiate between 2 cases:
a) if pdata->max_current is not set , or
b) pdata->max_current is set to AAT2870_CURRENT_0_45 (which is also 0).
Fix it by setting AAT2870_CURRENT_0_45 to be 1 and adjust the equation in
aat2870_brightness() accordingly.
Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Samuel Ortiz <sameo@linux.intel.com> Tested-by: Jin Park <jinyoungp@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Axel Lin [Wed, 3 Aug 2011 23:21:16 +0000 (16:21 -0700)]
drivers/video/backlight/aat2870_bl.c: fix error checking for backlight_device_register
backlight_device_register() returns ERR_PTR() on error.
Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Jin Park <jinyoungp@nvidia.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
WANG Cong [Wed, 3 Aug 2011 23:21:15 +0000 (16:21 -0700)]
cris: add missing declaration of kgdb_init() and breakpoint()
Fix:
arch/cris/arch-v10/kernel/irq.c:239: error: implicit declaration of function 'kgdb_init'
arch/cris/arch-v10/kernel/irq.c:240: error: implicit declaration of function 'breakpoint'
Declare these two functions.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Randy Dunlap [Wed, 3 Aug 2011 23:21:11 +0000 (16:21 -0700)]
tpm_tis: fix build when ACPI is not enabled
Fix tpm_tis.c build when CONFIG_ACPI is not enabled by providing a stub
function. Fixes many build errors/warnings:
drivers/char/tpm/tpm_tis.c:89: error: dereferencing pointer to incomplete type
drivers/char/tpm/tpm_tis.c:89: warning: type defaults to 'int' in declaration of 'type name'
drivers/char/tpm/tpm_tis.c:89: error: request for member 'list' in something not a structure or union
...
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Leendert van Doorn <leendert@watson.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: 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>
Johannes Weiner [Wed, 3 Aug 2011 23:21:09 +0000 (16:21 -0700)]
mm: page_alloc: increase __GFP_BITS_SHIFT to include __GFP_OTHER_NODE
__GFP_OTHER_NODE is used for NUMA allocations on behalf of other nodes.
It's supposed to be passed through from the page allocator to
zone_statistics(), but it never gets there as gfp_allowed_mask is not
wide enough and masks out the flag early in the allocation path.
The result is an accounting glitch where successful NUMA allocations
by-agent are not properly attributed as local.
Increase __GFP_BITS_SHIFT so that it includes __GFP_OTHER_NODE.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergiu Iordache [Wed, 3 Aug 2011 23:21:09 +0000 (16:21 -0700)]
ramoops: update module parameters
Update the module parameters when platform data is used. This means
that they can be read from /sys/module/ramoops/parameters in order to
parse the memory area.
Signed-off-by: Sergiu Iordache <sergiu@chromium.org> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Drewry [Wed, 3 Aug 2011 23:21:08 +0000 (16:21 -0700)]
Documentation: add pointer to name_to_dev_t for root= values
Update kernel-parameters.txt to point users to the authoritative comment
for name_to_dev_t. In addition, updates other places where some
name_to_dev_t behavior was discussed. All other references to root=
appear to be for explicit sample usage or just side comments when
discussing other kernel parameters.
Signed-off-by: Will Drewry <wad@chromium.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Wed, 3 Aug 2011 23:21:05 +0000 (16:21 -0700)]
taskstats: add_del_listener() should ignore !valid listeners
When send_cpu_listeners() finds the orphaned listener it marks it as
!valid and drops listeners->sem. Before it takes this sem for writing,
s->pid can be reused and add_del_listener() can wrongly try to re-use
this entry.
Oleg Nesterov [Wed, 3 Aug 2011 23:21:04 +0000 (16:21 -0700)]
taskstats: add_del_listener() shouldn't use the wrong node
1. Commit 26c4caea9d69 "don't allow duplicate entries in listener mode"
changed add_del_listener(REGISTER) so that "next_cpu:" can reuse the
listener allocated for the previous cpu, this doesn't look exactly
right even if minor.
Change the code to kfree() in the already-registered case, this case
is unlikely anyway so the extra kmalloc_node() shouldn't hurt but
looke more correct and clean.
2. use the plain list_for_each_entry() instead of _safe() to scan
listeners->list.
3. Remove the unneeded INIT_LIST_HEAD(&s->list), we are going to
list_add(&s->list).
Daniel Glöckner [Wed, 3 Aug 2011 23:21:02 +0000 (16:21 -0700)]
rtc-omap: fix initialization of control register
As the comment explains, the intention of the code is to clear the
OMAP_RTC_CTRL_MODE_12_24 bit, but instead it only clears the
OMAP_RTC_CTRL_SPLIT and OMAP_RTC_CTRL_AUTO_COMP bits, which should be
kept. OMAP_RTC_CTRL_DISABLE, OMAP_RTC_CTRL_SET_32_COUNTER,
OMAP_RTC_CTRL_TEST, and OMAP_RTC_CTRL_ROUND_30S are also better off
being cleared.
Signed-off-by: Daniel Glöckner <dg@emlix.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Wed, 3 Aug 2011 23:21:01 +0000 (16:21 -0700)]
fault-injection: add ability to export fault_attr in arbitrary directory
init_fault_attr_dentries() is used to export fault_attr via debugfs.
But it can only export it in debugfs root directory.
Per Forlin is working on mmc_fail_request which adds support to inject
data errors after a completed host transfer in MMC subsystem.
The fault_attr for mmc_fail_request should be defined per mmc host and
export it in debugfs directory per mmc host like
/sys/kernel/debug/mmc0/mmc_fail_request.
init_fault_attr_dentries() doesn't help for mmc_fail_request. So this
introduces fault_create_debugfs_attr() which is able to create a
directory in the arbitrary directory and replace
init_fault_attr_dentries().
[akpm@linux-foundation.org: extraneous semicolon, per Randy] Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Tested-by: Per Forlin <per.forlin@linaro.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: 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>
Mathias Krause [Wed, 3 Aug 2011 18:57:11 +0000 (14:57 -0400)]
ext4: use kzalloc in ext4_kzalloc()
Commit 9933fc0i (ext4: introduce ext4_kvmalloc(), ext4_kzalloc(), and
ext4_kvfree()) intruduced wrappers around k*alloc/vmalloc but introduced
a typo for ext4_kzalloc() by not using kzalloc() but kmalloc().
Shawn Guo [Wed, 3 Aug 2011 10:28:14 +0000 (11:28 +0100)]
dt: add of_alias_scan and of_alias_get_id
The patch adds function of_alias_scan to populate a global lookup
table with the properties of 'aliases' node and function
of_alias_get_id for drivers to find alias id from the lookup table.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
[grant.likely: add locking and rework parse loop] Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Kiran Patil [Wed, 3 Aug 2011 09:20:01 +0000 (09:20 +0000)]
tcm_fc: Handle DDP/SW fc_frame_payload_get failures in ft_recv_write_data
Problem: HW DDP context was not invalidated in case of ABORTS, etc...
This leads to the problem where memory pages which are used for DDP
as user descriptor could get reused for some other purpose (such as to
satisfy new memory allocation request either by kernel or user mode threads)
and since HW DDP context was not invalidated, HW continue to write to
those pages, hence causing memory corruption.
Fix: Either on incoming ABORTS or due to exchange time out, allowed the
target to cleanup HW DDP context if it was setup for respective ft_cmd.
Added new function to perform this cleanup, furthur it can be enhanced
for other cleanup activity. Fix ft_recv_write_data() to properly handle
fc_frame_payload_get to return pointer to payload if it exist. If there is
no payload which is most common case (+ve case in case if DDP is working
as expected, it will return NULL. Yes, scope of buf is limited to printk.
Invalidation of HW context (which is done inside ft_invl_hw_context() is
necessary in SUCCESS and FAILURE case of DDP. Hence invalidation is DONE
as long as there was DDP setup (whether it worked correctly or not,
NOTE: For some reason, if there is any error w.r.t DDP such as out of
order packet reception, HW simply post the full packet in rx queue.
Signed-off-by: Kiran Patil <kiran.patil@intel.com> Cc: Robert W Love <robert.w.love@intel.com> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Linus Torvalds [Wed, 3 Aug 2011 07:17:39 +0000 (21:17 -1000)]
Merge branch 'tools-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6
* 'tools-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
tools/power turbostat: fit output into 80 columns on snb-ep
tools/power x86_energy_perf_policy: fix print of uninitialized string
Linus Torvalds [Wed, 3 Aug 2011 07:17:02 +0000 (21:17 -1000)]
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (28 commits)
ACPI: delete stale reference in kernel-parameters.txt
ACPI: add missing _OSI strings
ACPI: remove NID_INVAL
thermal: make THERMAL_HWMON implementation fully internal
thermal: split hwmon lookup to a separate function
thermal: hide CONFIG_THERMAL_HWMON
ACPI print OSI(Linux) warning only once
ACPI: DMI workaround for Asus A8N-SLI Premium and Asus A8N-SLI DELUX
ACPI / Battery: propagate sysfs error in acpi_battery_add()
ACPI / Battery: avoid acpi_battery_add() use-after-free
ACPI: introduce "acpi_rsdp=" parameter for kdump
ACPI: constify ops structs
ACPI: fix CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS
ACPI: fix 80 char overflow
ACPI / Battery: Resolve the race condition in the sysfs_remove_battery()
ACPI / Battery: Add the check before refresh sysfs in the battery_notify()
ACPI / Battery: Add the hibernation process in the battery_notify()
ACPI / Battery: Rename acpi_battery_quirks2 with acpi_battery_quirks
ACPI / Battery: Change 16-bit signed negative battery current into correct value
ACPI / Battery: Add the power unit macro
...
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile/mm/init.c: trivial: use BUG_ON
arch/tile: remove useless set_fixmap_nocache() macro
arch/tile: add hypervisor-based character driver for SPI flash ROM
ioctl-number.txt: add the tile hardwall ioctl range
tile: use generic-y format for one-line asm-generic headers
clocksource: tile: convert to use clocksource_register_hz
Linus Torvalds [Wed, 3 Aug 2011 07:14:05 +0000 (21:14 -1000)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (31 commits)
Btrfs: don't call writepages from within write_full_page
Btrfs: Remove unused variable 'last_index' in file.c
Btrfs: clean up for find_first_extent_bit()
Btrfs: clean up for wait_extent_bit()
Btrfs: clean up for insert_state()
Btrfs: remove unused members from struct extent_state
Btrfs: clean up code for merging extent maps
Btrfs: clean up code for extent_map lookup
Btrfs: clean up search_extent_mapping()
Btrfs: remove redundant code for dir item lookup
Btrfs: make acl functions really no-op if acl is not enabled
Btrfs: remove remaining ref-cache code
Btrfs: remove a BUG_ON() in btrfs_commit_transaction()
Btrfs: use wait_event()
Btrfs: check the nodatasum flag when writing compressed files
Btrfs: copy string correctly in INO_LOOKUP ioctl
Btrfs: don't print the leaf if we had an error
btrfs: make btrfs_set_root_node void
Btrfs: fix oops while writing data to SSD partitions
Btrfs: Protect the readonly flag of block group
...
Fix up trivial conflicts (due to acl and writeback cleanups) in
- fs/btrfs/acl.c
- fs/btrfs/ctree.h
- fs/btrfs/extent_io.c
Linus Torvalds [Wed, 3 Aug 2011 06:49:57 +0000 (20:49 -1000)]
Merge branch 'devicetree/next' of git://git.secretlab.ca/git/linux-2.6
* 'devicetree/next' of git://git.secretlab.ca/git/linux-2.6:
MAINTAINERS: Add keyword match for of_match_table to device tree section
of: constify property name parameters for helper functions
input: xilinx_ps2: Add missing of_address.h header
of: address: use resource_size helper
* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-watchdog:
watchdog: Cleanup WATCHDOG_CORE help text
watchdog: Fix POST failure on ASUS P5N32-E SLI and similar boards
watchdog: shwdt: fix usage of mod_timer
Tony Luck [Tue, 2 Aug 2011 22:08:30 +0000 (15:08 -0700)]
efivars: fix warnings when CONFIG_PSTORE=n
drivers/firmware/efivars.c:161: warning: ‘utf16_strlen’ defined but not used
utf16_strlen() is only used inside CONFIG_PSTORE - make this "static inline"
to shut the compiler up [thanks to hpa for the suggestion].
drivers/firmware/efivars.c:602: warning: initialization from incompatible pointer type
Between v1 and v2 of this patch series we decided to make the "part" number
unsigned - but missed fixing the stub version of efi_pstore_write()
Acked-by: Matthew Garrett <mjg@redhat.com> Acked-by: Mike Waychison <mikew@google.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Shaohua Li [Thu, 28 Jul 2011 20:48:43 +0000 (13:48 -0700)]
ACPI: add missing _OSI strings
Linux supports some optional features, but it should notify the BIOS about
them via the _OSI method. Currently Linux doesn't notify any, which might
make such features not work because the BIOS doesn't know about them.
Jarosz has a system which needs this to make ACPI processor aggregator
device work.
Reported-by: "Jarosz, Sebastian" <sebastian.jarosz@intel.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
David Rientjes [Thu, 28 Jul 2011 20:48:43 +0000 (13:48 -0700)]
ACPI: remove NID_INVAL
b552a8c56db8 ("ACPI: remove NID_INVAL") removed the left over uses of
NID_INVAL, but didn't actually remove the definition. Remove it.
Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Jean Delvare [Thu, 28 Jul 2011 20:48:42 +0000 (13:48 -0700)]
thermal: make THERMAL_HWMON implementation fully internal
THERMAL_HWMON is implemented inside the thermal_sys driver and has no
effect on drivers implementing thermal zones, so they shouldn't see
anything related to it in <linux/thermal.h>. Making the THERMAL_HWMON
implementation fully internal has two advantages beyond the cleaner
design:
* This avoids rebuilding all thermal drivers if the THERMAL_HWMON
implementation changes, or if CONFIG_THERMAL_HWMON gets enabled or
disabled.
* This avoids breaking the thermal kABI in these cases too, which should
make distributions happy.
The only drawback I can see is slightly higher memory fragmentation, as
the number of kzalloc() calls will increase by one per thermal zone. But
I doubt it will be a problem in practice, as I've never seen a system with
more than two thermal zones.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Rene Herman <rene.herman@gmail.com> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Jean Delvare [Thu, 28 Jul 2011 20:48:41 +0000 (13:48 -0700)]
thermal: split hwmon lookup to a separate function
We'll soon need to reuse it.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Rene Herman <rene.herman@gmail.com> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Jean Delvare [Thu, 28 Jul 2011 20:48:40 +0000 (13:48 -0700)]
thermal: hide CONFIG_THERMAL_HWMON
It's about time to revert 16d752397301b9 ("thermal: Create
CONFIG_THERMAL_HWMON=n"). Anybody running a kernel >= 2.6.40 would also
be running a recent enough version of lm-sensors.
Actually having CONFIG_THERMAL_HWMON is pretty convenient so instead of
dropping it, we keep it but hide it.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Rene Herman <rene.herman@gmail.com> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Mark Brown [Tue, 2 Aug 2011 05:13:26 +0000 (14:13 +0900)]
MAINTAINERS: Add keyword match for of_match_table to device tree section
If a patch is working with an of_match_table it's probably adding an OF
binding to a driver in which case the binding ought to be reviewed by the
device tree folks to make sure that things like the device matches are set
up correctly.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Linus Walleij [Tue, 2 Aug 2011 09:29:24 +0000 (11:29 +0200)]
spi/pl022: remove function cannot exit
The remove function in the PL022 driver cannot abort the remove
function any way, so restructure the code so as not to make that
assumption. Remove will now proceed no matter whether it can
stop the transfer queue or not.
Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Mike Snitzer [Tue, 2 Aug 2011 11:32:08 +0000 (12:32 +0100)]
dm table: set flush capability based on underlying devices
DM has always advertised both REQ_FLUSH and REQ_FUA flush capabilities
regardless of whether or not a given DM device's underlying devices
also advertised a need for them.
Block's flush-merge changes from 2.6.39 have proven to be more costly
for DM devices. Performance regressions have been reported even when
DM's underlying devices do not advertise that they have a write cache.
Fix the performance regressions by configuring a DM device's flushing
capabilities based on those of the underlying devices' capabilities.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Milan Broz [Tue, 2 Aug 2011 11:32:08 +0000 (12:32 +0100)]
dm crypt: optionally support discard requests
Add optional parameter field to dmcrypt table and support
"allow_discards" option.
Discard requests bypass crypt queue processing. Bio is simple remapped
to underlying device.
Note that discard will be never enabled by default because of security
consequences. It is up to the administrator to enable it for encrypted
devices.
(Note that userspace cryptsetup does not understand new optional
parameters yet. Support for this will come later. Until then, you
should use 'dmsetup' to enable and disable this.)
Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add the ability to parse and use metadata devices to dm-raid. Although
not strictly required, without the metadata devices, many features of
RAID are unavailable. They are used to store a superblock and bitmap.
The role, or position in the array, of each device must be recorded in
its superblock. This is to help with fault handling, array reshaping,
and sanity checks. RAID 4/5/6 devices must be loaded in a specific order:
in this way, the 'array_position' field helps validate the correctness
of the mapping when it is loaded. It can be used during reshaping to
identify which devices are added/removed. Fault handling is impossible
without this field. For example, when a device fails it is recorded in
the superblock. If this is a RAID1 device and the offending device is
removed from the array, there must be a way during subsequent array
assembly to determine that the failed device was the one removed. This
is done by correlating the 'array_position' field and the bit-field
variable 'failed_devices'.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:06 +0000 (12:32 +0100)]
dm ioctl: forbid multiple device specifiers
Exactly one of name, uuid or device must be specified when referencing
an existing device. This removes the ambiguity (risking the wrong
device being updated) if two conflicting parameters were specified.
Previously one parameter got used and any others were ignored silently.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:06 +0000 (12:32 +0100)]
dm ioctl: introduce __get_dev_cell
Move logic to find device based on major/minor number to a separate
function __get_dev_cell (similar to __get_uuid_cell and __get_name_cell).
This makes the function __find_device_hash_cell more straightforward.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:06 +0000 (12:32 +0100)]
dm ioctl: fill in device parameters in more ioctls
Move parameter filling from find_device to __find_device_hash_cell.
This patch causes ioctls using __find_device_hash_cell
(DM_DEV_REMOVE_CMD, DM_DEV_SUSPEND_CMD - resume, DM_TABLE_CLEAR_CMD)
to return device parameters, bringing them into line with the other
ioctls.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Tue, 2 Aug 2011 11:32:06 +0000 (12:32 +0100)]
dm flakey: add corrupt_bio_byte feature
Add corrupt_bio_byte feature to simulate corruption by overwriting a byte at a
specified position with a specified value during intervals when the device is
"down".
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Tue, 2 Aug 2011 11:32:05 +0000 (12:32 +0100)]
dm flakey: support feature args
Add the ability to specify arbitrary feature flags when creating a
flakey target. This code uses the same target argument helpers that
the multipath target does.
Also remove the superfluous 'dm-flakey' prefixes from the error messages,
as they already contain the prefix 'flakey'.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:04 +0000 (12:32 +0100)]
dm snapshot: skip reading origin when overwriting complete chunk
If we write a full chunk in the snapshot, skip reading the origin device
because the whole chunk will be overwritten anyway.
This patch changes the snapshot write logic when a full chunk is written.
In this case:
1. allocate the exception
2. dispatch the bio (but don't report the bio completion to device mapper)
3. write the exception record
4. report bio completed
Callbacks must be done through the kcopyd thread, because callbacks must not
race with each other. So we create two new functions:
dm_kcopyd_prepare_callback: allocate a job structure and prepare the callback.
(This function must not be called from interrupt context.)
dm_kcopyd_do_callback: submit callback.
(This function may be called from interrupt context.)
Performance test (on snapshots with 4k chunk size):
without the patch:
non-direct-io sequential write (dd): 17.7MB/s
direct-io sequential write (dd): 20.9MB/s
non-direct-io random write (mkfs.ext2): 0.44s
with the patch:
non-direct-io sequential write (dd): 26.5MB/s
direct-io sequential write (dd): 33.2MB/s
non-direct-io random write (mkfs.ext2): 0.27s
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:04 +0000 (12:32 +0100)]
dm: ignore merge_bvec for snapshots when safe
Add a new flag DMF_MERGE_IS_OPTIONAL to struct mapped_device to indicate
whether the device can accept bios larger than the size its merge
function returns. When set, use this to send large bios to snapshots
which can split them if necessary. Snapshot I/O may be significantly
fragmented and this approach seems to improve peformance.
Before the patch, dm_set_device_limits restricted bio size to page size
if the underlying device had a merge function and the target didn't
provide a merge function. After the patch, dm_set_device_limits
restricts bio size to page size if the underlying device has a merge
function, doesn't have DMF_MERGE_IS_OPTIONAL flag and the target doesn't
provide a merge function.
The snapshot target can't provide a merge function because when the merge
function is called, it is impossible to determine where the bio will be
remapped. Previously this led us to impose a 4k limit, which we can
now remove if the snapshot store is located on a device without a merge
function. Together with another patch for optimizing full chunk writes,
it improves performance from 29MB/s to 40MB/s when writing to the
filesystem on snapshot store.
If the snapshot store is placed on a non-dm device with a merge function
(such as md-raid), device mapper still limits all bios to page size.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:02 +0000 (12:32 +0100)]
dm kcopyd: remove nr_pages field from job structure
The nr_pages field in struct kcopyd_job is only used temporarily in
run_pages_job() to count the number of required pages.
We can use a local variable instead.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Tue, 2 Aug 2011 11:32:01 +0000 (12:32 +0100)]
dm table: fix discard support
Remove 'discards_supported' from the dm_table structure. The same
information can be easily discovered from the table's target(s) in
dm_table_supports_discards().
Before this fix dm_table_supports_discards() would skip checking the
individual targets' 'discards_supported' flag if any one target in the
table didn't set num_discard_requests > 0. Now the per-target
'discards_supported' flag is effective at insuring the final DM device
advertises discard support. But, to be clear, targets that don't
support discards (!num_discard_requests) will not receive discard
requests.
Also DMWARN if a target sets 'discards_supported' override but forgets
to set 'num_discard_requests'.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 2 Aug 2011 11:32:01 +0000 (12:32 +0100)]
dm io: flush cpu cache with vmapped io
For normal kernel pages, CPU cache is synchronized by the dma layer.
However, this is not done for pages allocated with vmalloc. If we do I/O
to/from vmallocated pages, we must synchronize CPU cache explicitly.
Prior to doing I/O on vmallocated page we must call
flush_kernel_vmap_range to flush dirty cache on the virtual address.
After finished read we must call invalidate_kernel_vmap_range to
invalidate cache on the virtual address, so that accesses to the virtual
address return newly read data and not stale data from CPU cache.
This patch fixes metadata corruption on dm-snapshots on PA-RISC and
possibly other architectures with caches indexed by virtual address.
projects / linux-beck.git / log