Lee Schermerhorn [Sun, 19 Oct 2008 03:26:43 +0000 (20:26 -0700)]
SHM_LOCKED pages are unevictable
Shmem segments locked into memory via shmctl(SHM_LOCKED) should not be
kept on the normal LRU, since scanning them is a waste of time and might
throw off kswapd's balancing algorithms. Place them on the unevictable
LRU list instead.
Use the AS_UNEVICTABLE flag to mark address_space of SHM_LOCKed shared
memory regions as unevictable. Then these pages will be culled off the
normal LRU lists during vmscan.
Add new wrapper function to clear the mapping's unevictable state when/if
shared memory segment is munlocked.
Add 'scan_mapping_unevictable_page()' to mm/vmscan.c to scan all pages in
the shmem segment's mapping [struct address_space] for evictability now
that they're no longer locked. If so, move them to the appropriate zone
lru list.
Changes depend on [CONFIG_]UNEVICTABLE_LRU.
[kosaki.motohiro@jp.fujitsu.com: revert shm change] Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Sun, 19 Oct 2008 03:26:42 +0000 (20:26 -0700)]
Ramfs and Ram Disk pages are unevictable
Christoph Lameter pointed out that ram disk pages also clutter the LRU
lists. When vmscan finds them dirty and tries to clean them, the ram disk
writeback function just redirties the page so that it goes back onto the
active list. Round and round she goes...
With the ram disk driver [rd.c] replaced by the newer 'brd.c', this is no
longer the case, as ram disk pages are no longer maintained on the lru.
[This makes them unmigratable for defrag or memory hot remove, but that
can be addressed by a separate patch series.] However, the ramfs pages
behave like ram disk pages used to, so:
Define new address_space flag [shares address_space flags member with
mapping's gfp mask] to indicate that the address space contains all
unevictable pages. This will provide for efficient testing of ramfs pages
in page_evictable().
Also provide wrapper functions to set/test the unevictable state to
minimize #ifdefs in ramfs driver and any other users of this facility.
Set the unevictable state on address_space structures for new ramfs
inodes. Test the unevictable state in page_evictable() to cull
unevictable pages.
These changes depend on [CONFIG_]UNEVICTABLE_LRU.
[riel@redhat.com: undo the brd.c part] Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Debugged-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Sun, 19 Oct 2008 03:26:40 +0000 (20:26 -0700)]
unevictable lru: add event counting with statistics
Fix to unevictable-lru-page-statistics.patch
Add unevictable lru infrastructure vm events to the statistics patch.
Rename the "NORECL_" and "noreclaim_" symbols and text strings to
"UNEVICTABLE_" and "unevictable_", respectively.
Currently, both the infrastructure and the mlocked pages event are
added by a single patch later in the series. This makes it difficult
to add or rework the incremental patches. The events actually "belong"
with the stats, so pull them up to here.
Also, restore the event counting to putback_lru_page(). This was removed
from previous patch in series where it was "misplaced". The actual events
weren't defined that early.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Sun, 19 Oct 2008 03:26:39 +0000 (20:26 -0700)]
Unevictable LRU Infrastructure
When the system contains lots of mlocked or otherwise unevictable pages,
the pageout code (kswapd) can spend lots of time scanning over these
pages. Worse still, the presence of lots of unevictable pages can confuse
kswapd into thinking that more aggressive pageout modes are required,
resulting in all kinds of bad behaviour.
Infrastructure to manage pages excluded from reclaim--i.e., hidden from
vmscan. Based on a patch by Larry Woodman of Red Hat. Reworked to
maintain "unevictable" pages on a separate per-zone LRU list, to "hide"
them from vmscan.
Kosaki Motohiro added the support for the memory controller unevictable
lru list.
Pages on the unevictable list have both PG_unevictable and PG_lru set.
Thus, PG_unevictable is analogous to and mutually exclusive with
PG_active--it specifies which LRU list the page is on.
The unevictable infrastructure is enabled by a new mm Kconfig option
[CONFIG_]UNEVICTABLE_LRU.
A new function 'page_evictable(page, vma)' in vmscan.c tests whether or
not a page may be evictable. Subsequent patches will add the various
!evictable tests. We'll want to keep these tests light-weight for use in
shrink_active_list() and, possibly, the fault path.
To avoid races between tasks putting pages [back] onto an LRU list and
tasks that might be moving the page from non-evictable to evictable state,
the new function 'putback_lru_page()' -- inverse to 'isolate_lru_page()'
-- tests the "evictability" of a page after placing it on the LRU, before
dropping the reference. If the page has become unevictable,
putback_lru_page() will redo the 'putback', thus moving the page to the
unevictable list. This way, we avoid "stranding" evictable pages on the
unevictable list.
[akpm@linux-foundation.org: fix fallout from out-of-order merge]
[riel@redhat.com: fix UNEVICTABLE_LRU and !PROC_PAGE_MONITOR build]
[nishimura@mxp.nes.nec.co.jp: remove redundant mapping check]
[kosaki.motohiro@jp.fujitsu.com: unevictable-lru-infrastructure: putback_lru_page()/unevictable page handling rework]
[kosaki.motohiro@jp.fujitsu.com: kill unnecessary lock_page() in vmscan.c]
[kosaki.motohiro@jp.fujitsu.com: revert migration change of unevictable lru infrastructure]
[kosaki.motohiro@jp.fujitsu.com: revert to unevictable-lru-infrastructure-kconfig-fix.patch]
[kosaki.motohiro@jp.fujitsu.com: restore patch failure of vmstat-unevictable-and-mlocked-pages-vm-events.patch] Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Debugged-by: Benjamin Kidwell <benjkidwell@yahoo.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Sun, 19 Oct 2008 03:26:36 +0000 (20:26 -0700)]
more aggressively use lumpy reclaim
During an AIM7 run on a 16GB system, fork started failing around 32000
threads, despite the system having plenty of free swap and 15GB of
pageable memory. This was on x86-64, so 8k stacks.
If a higher order allocation fails, we can either:
- keep evicting pages off the end of the LRUs and hope that
we eventually create a contiguous region; this is somewhat
unlikely if the system is under enough stress by new
allocations
- after trying normal eviction for a bit, use lumpy reclaim
This patch switches the system to lumpy reclaim if the VM is having
trouble freeing enough pages, using the same threshold for detection as
used by pageout congestion wait.
Signed-off-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>
Rik van Riel [Sun, 19 Oct 2008 03:26:36 +0000 (20:26 -0700)]
vmscan: add newly swapped in pages to the inactive list
Swapin_readahead can read in a lot of data that the processes in memory
never need. Adding swap cache pages to the inactive list prevents them
from putting too much pressure on the working set.
This has the potential to help the programs that are already in memory,
but it could also be a disadvantage to processes that are trying to get
swapped in.
Signed-off-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>
Rik van Riel [Sun, 19 Oct 2008 03:26:35 +0000 (20:26 -0700)]
vmscan: fix pagecache reclaim referenced bit check
Moving referenced pages back to the head of the active list creates a huge
scalability problem, because by the time a large memory system finally
runs out of free memory, every single page in the system will have been
referenced.
Not only do we not have the time to scan every single page on the active
list, but since they have will all have the referenced bit set, that bit
conveys no useful information.
A more scalable solution is to just move every page that hits the end of
the active list to the inactive list.
We clear the referenced bit off of mapped pages, which need just one
reference to be moved back onto the active list.
Unmapped pages will be moved back to the active list after two references
(see mark_page_accessed). We preserve the PG_referenced flag on unmapped
pages to preserve accesses that were made while the page was on the active
list.
Signed-off-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>
Rik van Riel [Sun, 19 Oct 2008 03:26:34 +0000 (20:26 -0700)]
vmscan: second chance replacement for anonymous pages
We avoid evicting and scanning anonymous pages for the most part, but
under some workloads we can end up with most of memory filled with
anonymous pages. At that point, we suddenly need to clear the referenced
bits on all of memory, which can take ages on very large memory systems.
We can reduce the maximum number of pages that need to be scanned by not
taking the referenced state into account when deactivating an anonymous
page. After all, every anonymous page starts out referenced, so why
check?
If an anonymous page gets referenced again before it reaches the end of
the inactive list, we move it back to the active list.
To keep the maximum amount of necessary work reasonable, we scale the
active to inactive ratio with the size of memory, using the formula
active:inactive ratio = sqrt(memory in GB * 10).
Kswapd CPU use now seems to scale by the amount of pageout bandwidth,
instead of by the amount of memory present in the system.
Rik van Riel [Sun, 19 Oct 2008 03:26:32 +0000 (20:26 -0700)]
vmscan: split LRU lists into anon & file sets
Split the LRU lists in two, one set for pages that are backed by real file
systems ("file") and one for pages that are backed by memory and swap
("anon"). The latter includes tmpfs.
The advantage of doing this is that the VM will not have to scan over lots
of anonymous pages (which we generally do not want to swap out), just to
find the page cache pages that it should evict.
This patch has the infrastructure and a basic policy to balance how much
we scan the anon lists and how much we scan the file lists. The big
policy changes are in separate patches.
[lee.schermerhorn@hp.com: collect lru meminfo statistics from correct offset]
[kosaki.motohiro@jp.fujitsu.com: prevent incorrect oom under split_lru]
[kosaki.motohiro@jp.fujitsu.com: fix pagevec_move_tail() doesn't treat unevictable page]
[hugh@veritas.com: memcg swapbacked pages active]
[hugh@veritas.com: splitlru: BDI_CAP_SWAP_BACKED]
[akpm@linux-foundation.org: fix /proc/vmstat units]
[nishimura@mxp.nes.nec.co.jp: memcg: fix handling of shmem migration]
[kosaki.motohiro@jp.fujitsu.com: adjust Quicklists field of /proc/meminfo]
[kosaki.motohiro@jp.fujitsu.com: fix style issue of get_scan_ratio()] Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Sun, 19 Oct 2008 03:26:30 +0000 (20:26 -0700)]
define page_file_cache() function
Define page_file_cache() function to answer the question:
is page backed by a file?
Originally part of Rik van Riel's split-lru patch. Extracted to make
available for other, independent reclaim patches.
Moved inline function to linux/mm_inline.h where it will be needed by
subsequent "split LRU" and "noreclaim" patches.
Unfortunately this needs to use a page flag, since the PG_swapbacked state
needs to be preserved all the way to the point where the page is last
removed from the LRU. Trying to derive the status from other info in the
page resulted in wrong VM statistics in earlier split VM patchsets.
The total number of page flags in use on a 32 bit machine after this patch
is 19.
[akpm@linux-foundation.org: fix up out-of-order merge fallout]
[hugh@veritas.com: splitlru: shmem_getpage SetPageSwapBacked sooner[ Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: MinChan Kim <minchan.kim@gmail.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Sun, 19 Oct 2008 03:26:23 +0000 (20:26 -0700)]
vmscan: free swap space on swap-in/activation
If vm_swap_full() (swap space more than 50% full), the system will free
swap space at swapin time. With this patch, the system will also free the
swap space in the pageout code, when we decide that the page is not a
candidate for swapout (and just wasting swap space).
Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: MinChan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KOSAKI Motohiro [Sun, 19 Oct 2008 03:26:19 +0000 (20:26 -0700)]
swap: use an array for the LRU pagevecs
Turn the pagevecs into an array just like the LRUs. This significantly
cleans up the source code and reduces the size of the kernel by about 13kB
after all the LRU lists have been created further down in the split VM
patch series.
Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we are defining explicit variables for the inactive and active
list. An indexed array can be more generic and avoid repeating similar
code in several places in the reclaim code.
Nick Piggin [Sun, 19 Oct 2008 03:26:09 +0000 (20:26 -0700)]
vmscan: move isolate_lru_page() to vmscan.c
On large memory systems, the VM can spend way too much time scanning
through pages that it cannot (or should not) evict from memory. Not only
does it use up CPU time, but it also provokes lock contention and can
leave large systems under memory presure in a catatonic state.
This patch series improves VM scalability by:
1) putting filesystem backed, swap backed and unevictable pages
onto their own LRUs, so the system only scans the pages that it
can/should evict from memory
2) switching to two handed clock replacement for the anonymous LRUs,
so the number of pages that need to be scanned when the system
starts swapping is bound to a reasonable number
3) keeping unevictable pages off the LRU completely, so the
VM does not waste CPU time scanning them. ramfs, ramdisk,
SHM_LOCKED shared memory segments and mlock()ed VMA pages
are keept on the unevictable list.
This patch:
isolate_lru_page logically belongs to be in vmscan.c than migrate.c.
It is tough, because we don't need that function without memory migration
so there is a valid argument to have it in migrate.c. However a
subsequent patch needs to make use of it in the core mm, so we can happily
move it to vmscan.c.
Also, make the function a little more generic by not requiring that it
adds an isolated page to a given list. Callers can do that.
Note that we now have '__isolate_lru_page()', that does
something quite different, visible outside of vmscan.c
for use with memory controller. Methinks we need to
rationalize these names/purposes. --lts
[akpm@linux-foundation.org: fix mm/memory_hotplug.c build] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Badari Pulavarty [Sun, 19 Oct 2008 03:25:58 +0000 (20:25 -0700)]
mm: cleanup to make remove_memory() arch-neutral
There is nothing architecture specific about remove_memory().
remove_memory() function is common for all architectures which support
hotplug memory remove. Instead of duplicating it in every architecture,
collapse them into arch neutral function.
[akpm@linux-foundation.org: fix the export] Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Gary Hade <garyhade@us.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stephen Rothwell [Sun, 19 Oct 2008 03:25:46 +0000 (20:25 -0700)]
tpm: don't export static functions
Today's linux-next build (powerpc_allyesconfig) failed like this:
drivers/char/tpm/tpm.c:1162: error: __ksymtab_tpm_dev_release causes a section type conflict
Caused by commit 253115b71fa06330bd58afbe01ccaf763a8a0cf1 ("The
tpm_dev_release function is only called for platform devices, not pnp")
which exported a static function.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Rajiv Andrade <srajiv@linux.vnet.ibm.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Brown [Sun, 19 Oct 2008 03:25:41 +0000 (20:25 -0700)]
mailmap: add Mark Brown
A couple of commits have a broken real name - fix them up.
Signed-off-by: Mark Brown <broonie@sirena.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sun, 19 Oct 2008 17:32:20 +0000 (10:32 -0700)]
anon_vma_prepare: properly lock even newly allocated entries
The anon_vma code is very subtle, and we end up doing optimistic lookups
of anon_vmas under RCU in page_lock_anon_vma() with no locking. Other
CPU's can also see the newly allocated entry immediately after we've
exposed it by setting "vma->anon_vma" to the new value.
We protect against the anon_vma being destroyed by having the SLAB
marked as SLAB_DESTROY_BY_RCU, so the RCU lookup can depend on the
allocation not being destroyed - but it might still be free'd and
re-allocated here to a new vma.
As a result, we should not do the anon_vma list ops on a newly allocated
vma without proper locking.
Acked-by: Nick Piggin <npiggin@suse.de> Acked-by: Hugh Dickins <hugh@veritas.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (94 commits)
USB: remove err() macro from more usb drivers
USB: remove err() macro from usb misc drivers
USB: remove err() macro from usb core code
USB: remove err() macro from usb class drivers
USB: remove use of err() in drivers/usb/serial
USB: remove info() macro from usb mtd drivers
USB: remove info() macro from usb input drivers
USB: remove info() macro from usb network drivers
USB: remove info() macro from remaining usb drivers
USB: remove info() macro from usb/misc drivers
USB: remove info() macro from usb/serial drivers
USB: remove warn macro from HID core
USB: remove warn() macro from usb drivers
USB: remove warn() macro from usb net drivers
USB: remove warn() macro from usb media drivers
USB: remove warn() macro from usb input drivers
usb/fsl_qe_udc: clear data toggle on clear halt request
usb/fsl_qe_udc: fix response to get status request
fsl_usb2_udc: Fix oops on probe failure.
fsl_usb2_udc: Add a wmb before priming endpoint.
...
Linus Torvalds [Fri, 17 Oct 2008 22:09:20 +0000 (15:09 -0700)]
Merge branch 'drm-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6
* 'drm-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (44 commits)
drm/i915: fix ioremap of a user address for non-root (CVE-2008-3831)
drm: make CONFIG_DRM depend on CONFIG_SHMEM.
radeon: fix PCI bus mastering support enables.
radeon: add RS400 family support.
drm/radeon: add support for RS740 IGP chipsets.
i915: GM45 has GM965-style MCH setup.
i915: Don't run retire work handler while suspended
i915: Map status page cached for chips with GTT-based HWS location.
i915: Fix up ring initialization to cover G45 oddities
i915: Use non-reserved status page index for breadcrumb
drm: Increment dev_priv->irq_received so i915_gem_interrupts count works.
drm: kill drm_device->irq
drm: wbinvd is cache coherent.
i915: add missing return in error path.
i915: fixup permissions on gem ioctls.
drm: Clean up many sparse warnings in i915.
drm: Use ioremap_wc in i915_driver instead of ioremap, since we always want WC.
drm: G33-class hardware has a newer 965-style MCH (no DCC register).
drm: Avoid oops in GEM execbuffers with bad arguments.
DRM: Return -EBADF on bad object in flink, and return curent name if it exists.
...
Linus Torvalds [Fri, 17 Oct 2008 22:08:47 +0000 (15:08 -0700)]
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (95 commits)
V4L/DVB (9296): Patch to remove warning message during cx88-dvb compilation
V4L/DVB (9294): gspca: Add a stop sequence in t613.
V4L/DVB (9293): gspca: Separate and fix the sensor dependant sequences in t613.
V4L/DVB (9292): gspca: Call the control setting functions at init time in t613.
V4L/DVB (9291): gspca: Do not set the white balance temperature by default in t613.
V4L/DVB (9290): gspca: Adjust the sensor init sequences in t613.
V4L/DVB (9289): gspca: Other sensor identified as om6802 in t613.
V4L/DVB (9288): gspca: Write to the USB device and not USB interface in t613.
V4L/DVB (9287): gspca: Change the name of the multi bytes write function in t613.
V4L/DVB (9286): gspca: Compilation problem of gspca.c and the kernel version.
V4L/DVB (9283): Correct typo and enable setting the gain on the mt9m111 sensor
V4L/DVB (9282): Properly iterate the urbs when destroying them.
V4L/DVB (9281): gspca: Add hflip and vflip to the po1030 sensor
V4L/DVB (9280): gspca: Use the gspca debug macros
V4L/DVB (9279): gspca: Correct some copyright headers
V4L/DVB (9278): gspca: Remove the m5602_debug variable
V4L/DVB (9277): gspca: propagate an error in m5602_start_transfer()
V4L/DVB (9276): videobuf-dvb: two functions are now static
V4L/DVB (9275): dvb: input data pointer of cx24116_writeregN() should be const
V4L/DVB (9274): Remove spurious messages and turn into debug.
...
Linus Torvalds [Fri, 17 Oct 2008 22:08:11 +0000 (15:08 -0700)]
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Remove automatic enabling of the HUGE_FILE feature flag
ext4: Replace hackish ext4_mb_poll_new_transaction with commit callback
ext4: Update Documentation/filesystems/ext4.txt
ext4: Remove unused mount options: nomballoc, mballoc, nocheck
ext4: Remove compile warnings when building w/o CONFIG_PROC_FS
ext4: Add missing newlines to printk messages
ext4: Fix file fragmentation during large file write.
vfs: Add no_nrwrite_index_update writeback control flag
vfs: Remove the range_cont writeback mode.
ext4: Use tag dirty lookup during mpage_da_submit_io
ext4: let the block device know when unused blocks can be discarded
ext4: Don't reuse released data blocks until transaction commits
ext4: Use an rbtree for tracking blocks freed during transaction.
ext4: Do mballoc init before doing filesystem recovery
ext4: Free ext4_prealloc_space using kmem_cache_free
ext4: Fix Kconfig typo for ext4dev
ext4: Remove an old reference to ext4dev in Makefile comment
USB should not be having it's own printk macros, so remove err() and
use the system-wide standard of dev_err() wherever possible. In the
few places that will not work out, use a basic printk().
USB should not be having it's own printk macros, so remove err() and
use the system-wide standard of dev_err() wherever possible. In the
few places that will not work out, use a basic printk().
USB should not be having it's own printk macros, so remove err() and
use the system-wide standard of dev_err() wherever possible. In the
few places that will not work out, use a basic printk().
USB should not be having it's own printk macros, so remove err() and
use the system-wide standard of dev_err() wherever possible. In the
few places that will not work out, use a basic printk().
USB: remove info() macro from remaining usb drivers
USB should not be having it's own printk macros, so remove info() and
use the system-wide standard of dev_info() wherever possible. In the
few places that will not work out, use a basic printk().
Clean up the remaining usages of this in the drivers/usb/ directory.
There were two stragglers that got missed in the last merge of the HID tree that forgot to change the warn() calls to dev_warn(). This patch fixes them up.
USB should not be having it's own printk macros, so remove warn() and
use the system-wide standard of dev_warn() wherever possible. In the
few places that will not work out, use a basic printk().
USB should not be having it's own printk macros, so remove warn() and
use the system-wide standard of dev_warn() wherever possible. In the
few places that will not work out, use a basic printk().
Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
USB should not be having it's own printk macros, so remove warn() and
use the system-wide standard of dev_warn() wherever possible. In the
few places that will not work out, use a basic printk().
USB should not be having it's own printk macros, so remove warn() and
use the system-wide standard of dev_warn() wherever possible. In the
few places that will not work out, use a basic printk().
Li Yang [Wed, 24 Sep 2008 07:50:26 +0000 (15:50 +0800)]
usb/fsl_qe_udc: fix response to get status request
The original code didn't respond correctly to get status request on
device and endpoint. Although normal operations can work without the
fix. It is not compliant with USB spec chapter9 and fails USBCV ch9
tests. The patch fix this and a few style/typo problems.
Signed-off-by: Li Yang <leoli@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Will Newton [Tue, 12 Aug 2008 14:39:17 +0000 (15:39 +0100)]
fsl_usb2_udc: Fix oops on probe failure.
In some circumstances when fsl_udc_probe fails udc_controller is freed but
the pointer remains non-NULL. fsl_udc_remove will then try and teardown
the partly initialized and freed controller structure resulting in an oops.
This patch ensures udc_controller is either NULL or fully initialized after
fsl_udc_probe.
Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: Li Yang <leoli@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Will Newton [Tue, 12 Aug 2008 14:39:09 +0000 (15:39 +0100)]
fsl_usb2_udc: Fix some sparse warnings and remove redundant code.
Fix some sparse "integer used as NULL pointer" warnings.
Remove some unnecessary volatiles and static initialization.
Remove some unused struct members and reorder to improve packing.
Remove a few unneeded includes.
Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: Li Yang <leoli@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Stephen Ware [Wed, 8 Oct 2008 17:53:56 +0000 (10:53 -0700)]
USB: fix up problems in the vtusb driver
Add range check on buffer sizes passed in from user space
(max is 8*PAGE_SIZE) which will work for the most common
spectrometers even at pages as small as 1K.
Add kref to vst device structure to preserve reference to the
usb object until we truly are done with it.
From: Stephen Ware <stephen.ware@eqware.net>
From: Dennis O'Brien <dennis.obrien@eqware.net> Signed-off-by: Dennis O'Brien <dennis.obrien@eqware.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Thu, 9 Oct 2008 19:40:23 +0000 (15:40 -0400)]
USB: OHCI: fix endless polling behavior
This patch (as1149) fixes an obscure problem in OHCI polling. In the
current code, if the RHSC interrupt status flag turns on at a time
when RHSC interrupts are disabled, it will remain on forever:
The interrupt handler is the only place where RHSC status
gets turned back off;
The interrupt handler won't turn RHSC status off because it
doesn't turn off status flags if the corresponding interrupt
isn't enabled;
RHSC interrupts will never get enabled because
ohci_root_hub_state_changes() doesn't reenable RHSC if RHSC
status is on!
As a result we will continue polling indefinitely instead of reverting
to interrupt-driven operation, and the root hub will not autosuspend.
This particular sequence of events is not at all unusual; in fact
plugging a USB device into an OHCI controller will usually cause it to
occur.
Of course, this is a bug. The proper thing to do is to turn off RHSC
status just before reading the actual port status values. That way
either a port status change will be detected (if it occurs before the
status read) or it will turn RHSC back on. Possibly both, but that
won't hurt anything.
We can still check for systems in which RHSC is totally broken, by
re-reading RHSC after clearing it and before reading the port
statuses. (This re-read has to be done anyway, to post the earlier
write.) If RHSC is on but no port-change statuses are set, then we
know that RHSC is broken and we can avoid re-enabling it.
Jaroslav Kysela [Fri, 10 Oct 2008 14:24:45 +0000 (16:24 +0200)]
USB: hub.c: Add initial_descriptor_timeout module parameter for usbcore
This patch adds initial_descriptor_timeout module parameter for usbcore.ko
to allow modify initial 64-byte USB_REQ_GET_DESCRIPTOR timeout for
non-standard devices.
For example, the SATA8000 device from DATAST0R Technology Corp
requires about 10 seconds to send reply (probably it waits until
inserted disk is ready for operation).
Also, this patch adds missing usbcore parameters to
Documentation/kernel-parameters.txt.
Signed-off-by: Jaroslav Kysela <perex@perex.cz> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Sarah Sharp [Mon, 6 Oct 2008 21:45:46 +0000 (14:45 -0700)]
USB: Export if an interface driver supports autosuspend.
Create a new sysfs file per interface named supports_autosuspend. This
file returns true if an interface driver's .supports_autosuspend flag is
set. It also returns true if the interface is unclaimed (since the USB
core will autosuspend a device if an interface is not claimed).
This new sysfs file will be useful for user space scripts to test whether
a USB device correctly auto-suspends.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Oliver Neukum <oliver@neukum.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Mon, 6 Oct 2008 15:25:53 +0000 (11:25 -0400)]
USB: EHCI: fix remote-wakeup support for ARC/TDI core
This patch (as1147) fixes the remote-wakeup support for EHCI
controllers using the ARC/TDI "embedded-TT" core. These controllers
turn off the RESUME bit by themselves when a port resume is complete;
hence we need to keep separate track of which ports are suspended or
in the process of resuming.
The patch also makes a couple of small improvements in ehci_irq(),
replacing reads of the command register with the value already stored
in a local variable.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Thomas Reitmayr <treitmayr@devbase.at> CC: David Brownell <david-b@pacbell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Mon, 6 Oct 2008 15:24:26 +0000 (11:24 -0400)]
USB: snoop processes opening usbfs device files
This patch (as1148) adds a new "snoop" message to usbfs when a device
file is opened, identifying the process responsible. This comes in
extremely handy when trying to determine which program is doing some
unwanted USB access.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Thu, 2 Oct 2008 15:48:13 +0000 (11:48 -0400)]
USB: EHCI: log a warning if ehci-hcd is not loaded first
This patch (as1139) adds a warning to the system log whenever ehci-hcd
is loaded after ohci-hcd or uhci-hcd. Nowadays most distributions are
pretty good about not doing this; maybe the warning will help convince
anyone still doing it wrong.
Alan Stern [Thu, 2 Oct 2008 15:47:15 +0000 (11:47 -0400)]
USB: EHCI, OHCI, UHCI: remove version numbers
This patch (as1145) removes the essentially useless driver-version
strings from ehci-hcd, ohci-hcd, and uhci-hcd. It also unifies the
form of the banner lines they display upon loading and adds a missing
test for usb_disabled() to ehci-hcd.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Sarah Sharp [Mon, 29 Sep 2008 17:58:35 +0000 (10:58 -0700)]
USB: ftdi-elan: Always pass usb_bulk_msg() a timeout in milliseconds.
The kernel doc for usb_bulk_msg() says the timeout for a bulk message should be
specified in milliseconds. The ftdi-elan driver converts milliseconds to
jiffies before passing the timeout to usb_bulk_msg(). This is mostly harmless,
since it will just lead to very long timeouts, but was obviously not the intent
of the original author.
Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com> Acked-by: Tony Olech <tony.olech@elandigitalsystems.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
USB: isp1760: Use an IS_ERR test rather than a NULL test
In case of error, the function isp1760_register returns an ERR
pointer, but never returns a NULL pointer. So after a call to this
function, a NULL test should be replaced by an IS_ERR test. Moreover,
we have noticed that:
(1) the result of isp1760_register is assigned through the function
pci_set_drvdata without an error test,
(2) if the call to isp1760_register fails, the current function
(isp1761_pci_probe) returns 0, and if it succeeds, it returns -ENOMEM,
which seems odd.
Thus, we suggest to move the test before the call to pci_set_drvdata
to correct (1), and to turn it into a non IS_ERR test to correct (2).
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@bad_null_test@
expression x,E;
statement S1, S2;
@@
x = isp1760_register(...)
... when != x = E
* if (x == NULL)
S1 else S2
// </smpl>
Yi Yang [Thu, 25 Sep 2008 09:25:44 +0000 (17:25 +0800)]
USB: improve ehci_watchdog's side effect in CPU power management
ehci_watchdog will wake up CPU very frequently so that CPU
stays at C3 very short, average residence time is about 50
ms on Aspire One, but we expect it should be about 1 second
or more, so this kind of periodic timer is very bad for power
saving.
We can't remove this timer because of some bad USB controller
chipset, but at least we should reduce its side effect to as
possible as low.
This patch can make CPU stay at C3 longer, average residence time
is about twice as long as original.
Please consider to apply it, thanks
Signed-off-by: Yi Yang <yi.y.yang@intel.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Thu, 25 Sep 2008 20:59:57 +0000 (16:59 -0400)]
USB: UHCI: improve scheduling of interrupt URBs
This patch (as1140) adds a little intelligence to the interrupt-URB
scheduler in uhci-hcd. Right now the scheduler is stupid; every URB
having the same period is assigned to the same slot. Thus a large
group of period-N URBs can fill their slot and cause -ENOSPC errors
even when all the lower-period slots are empty.
With the patch, if an URB doesn't fit in its assigned slot then the
scheduler will try using lower-period slots. This will provide
greater flexibility. As an example, the driver will be able to handle
more than just three or four mice, which the current driver cannot.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Stephen Ware [Tue, 30 Sep 2008 18:39:38 +0000 (11:39 -0700)]
usb: vstusb.c : new driver for spectrometers used by Vernier Software & Technology, Inc.
This patch adds the vstusb driver to the drivers/usb/misc directory.
This driver provides support for Vernier Software & Technology
spectrometers, all made by Ocean Optics. The driver provides both IOCTL
and read()/write() methods for sending raw data to spectrometers across
the bulk channel. Each method allows for a configured timeout.
From: Stephen Ware <stephen.ware@eqware.net> Signed-off-by: Dennis O'Brien <dennis.obrien@eqware.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Sun, 7 Sep 2008 04:33:49 +0000 (21:33 -0700)]
usb gadget: cdc ethernet notification bugfix
Bugfix for the new CDC Ethernet code: as part of activating the
network interface's USB link, make sure its link management code
knows whether the interface is open or not.
Without this fix, the link won't work right when it's brought up
before the link is active ... because the initial notification it
sends will have the wrong link state (down, not up). Makes it
hard to bridge these links (on the host side), among other things.
Tony Lindgren [Thu, 4 Sep 2008 23:25:14 +0000 (16:25 -0700)]
USB: omap_udc: sync with OMAP tree
Sync up USB parts of the omap_udc support in mainline with the OMAP tree.
This patch addresses some OMAP2 differences ... there's another, with
respect to the double-buffering issue with PIO-IN in omap_ep_setup()
(which is now out of sync with the comments), but it's not clear right
now how to address that.
From: Tony Lindgren <tony@atomide.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Tony Lindgren [Thu, 4 Sep 2008 23:29:55 +0000 (16:29 -0700)]
USB: ohci-omap: handle other omap15xx chips
Sync up USB parts of the ohci-omap support in mainline with the OMAP tree.
This patch supports another first generation OMAP1 part: not just the
OMAP 1510 (and its catalog version, the OMAP 5910), but also OMAP 310.
From: Tony Lindgren <tony@atomide.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Felipe Balbi [Thu, 11 Sep 2008 08:53:25 +0000 (11:53 +0300)]
usb: musb: remove dead code from procfs
When removing the procfs file, I forgot to remove some
code that created and removed that file. Here's a patch
to fix it. Ideally this patch will be melded into the patch
removing the procfs file, don't know if it's possible still.
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Thu, 11 Sep 2008 08:53:23 +0000 (11:53 +0300)]
usb: musb_hdrc build fixes
Minor musb_hdrc updates:
- so it'll build on DaVinci, given relevant platform updates;
* remove support for an un-shipped OTG prototype
* rely on gpiolib framework conversion for the I2C GPIOs
* the <asm/arch/hdrc_cnf.h> mechanism has been removed
- catch comments up to the recent removal of the per-SOC header
with the silicon configuration data;
- and remove two inappropriate "inline" declarations which
just bloat host side code.
There are still some more <asm/arch/XYZ.h> ==> <mach/XYZ.h>
changes needed in this driver, catching up to the relocation
of most of the include/asm-arm/arch-* contents.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com> Cc: stable <stable@kernel.org> [2.6.27] Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fixes kernel panic while ISO IN transfer is aborted.Replaced
usb_hcd_unlink_urb_from_ep() from musb_giveback() to __musb_giveback()
to make sure urb is unlinked before giveback when __musb_giveback() is
called from musb_urb_dequeue().
Acquired musb->lock() before usb_hcd_unlink_urb_from_ep() within in
enqueue path.
Fixes enumeration failures when a USB device attached to a LS hub is
connected to OMAP EVM via HS hub. This is fixed by correctly
programming hub address register in enqueue path.
Felipe Balbi [Thu, 11 Sep 2008 08:53:19 +0000 (11:53 +0300)]
musb: io: only define read/write stubs if they're not defined yet
For those archs which don't provide read/write friends we
provide our own implementation so musb driver won't break
compilation.
This is temporary fix until a better solution comes from
upstream. Idealy, <linux/io.h> would provide those calls
if the architecture did not provide them yet. In that case
being possible to remove all those stubs from musb_io.h
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The new composite framework revealed a weakness in the
s3c2410_udc driver gadget register function. Instead of
checking if speed asked for was USB_LOW_SPEED upon
usb_gadget_register() to deny service, it checked only
for USB_FULL_SPEED, thus denying service to usb high
speed capable gadgets (like g_ether).
David Brownell [Fri, 12 Sep 2008 16:39:06 +0000 (09:39 -0700)]
usb gadget: USB_GADGET_VBUS_DRAW Kconfig option
Offer a "how much VBUS power to request" configuration option
for USB gadgets that aren't using board-specific customization
of their gadget or (composite) configuration drivers.
Also remove a couple pointless "depends on USB_GADGET" bits
from the Kconfig text; booleans inside an "if USB_GADGET" will
already have that dependency.
Based on a patch from Justin Clacherty.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Justin Clacherty <justin@redfish-group.com> Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Kevin Hilman [Mon, 15 Sep 2008 10:09:31 +0000 (12:09 +0200)]
MUSB: Add sanity check for maximum number of endpoints
There is no check if platform code passes in more endpoints (num_eps)
than the maximum number of enpoints (MUSB_C_NUM_EPS.) The result is
that allocate_instance() happily writes past the end of 'struct musb'
corrupting memory.
This patch adds a BUG() if the platform code requests more than the max.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Acked-by: Felipe Balbi <felipe.balbi@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Kumar Gala [Mon, 22 Sep 2008 22:00:07 +0000 (15:00 -0700)]
usb: remove code associated with !CONFIG_PPC_MERGE
Now that arch/ppc is gone we don't need CONFIG_PPC_MERGE anymore remove
the dead code associated with !CONFIG_PPC_MERGE.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Arjan van de Ven [Mon, 22 Sep 2008 22:00:10 +0000 (15:00 -0700)]
usbmon: fix tiny race exposed by the fastboot patches
usbmon registers the notifier chain, takes the bus lock and then goes to
scan the existing devices for hooking up.
Unfortunately, if usb_mon gets initialized while USB bus discovery is
going on, it's possible that usbmon gets a notifier on one cpu (which runs
without USB locks), and the scan is going on and also finds the new bus,
resulting in a double sysfs registration, which then produces a WARNING.
Pete Zaitcev did the bug diagnostics on this one
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Pete Zaitcev <zaitcev@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Mon, 22 Sep 2008 18:44:26 +0000 (14:44 -0400)]
USB: change hub initialization sleeps to delayed_work
This patch (as1137) changes the hub_activate() routine, replacing the
power-power-up and debounce delays with delayed_work calls. The idea
is that on systems where the USB stack is compiled into the kernel
rather than built as modules, these delays will no longer block the
boot thread. At least 100 ms is saved for each root hub, which can
add up to a significant savings in total boot time.
Arjan van de Ven was very pleased to see that this shaved 700 ms off
his computer's boot time. Since his total boot time is on the order
of two seconds, the improvement is considerable.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ming Lei [Thu, 18 Sep 2008 15:06:38 +0000 (23:06 +0800)]
USB: ehci-dbg: fix reading less content of periodic file
This patch fix 2 problems about reading periodic file:
1. The "..." after a interrupt qh is missed because buffer pointer is
not moved.
2. After setting p.ptr as NULL, its next qh or itd will be omited and
can't be stored in debug buffer.
Signed-off-by: Ming Lei <tom.leiming@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ming Lei [Thu, 18 Sep 2008 15:06:21 +0000 (23:06 +0800)]
USB: ehci-dbg: increase debug buffer size for periodic file
This patch is based on the following ideas:
1. Some usb devices (such as usb video class) have endpoints of high
interval attribute, so reading "periodic" file need more debug buffer
to accommodate the qh or itd schedule information. For example, 4KB
buffer is not enough for a single interrupt qh of 2ms period.
2. print a %p need 16 byte buffer on 64-bits arch, but 8 byte on 32-bits
arch. Add a extra bonus for 64-bits arch.
Signed-off-by: Ming Lei <tom.leiming@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Oliver Neukum [Mon, 15 Sep 2008 15:29:28 +0000 (17:29 +0200)]
USB: RESET_RESUME needs to block autosuspend when remote wakeup is needed
Reset upon resumption will wipe the input buffer and is therefore
a reason to not suspend if remote wakeup is requested because
the driver needs that data.
Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Wed, 3 Sep 2008 20:38:32 +0000 (16:38 -0400)]
OHCI: Allow broken controllers to auto-stop
This patch (as1134) attempts to improve the way we handle OHCI
controllers with broken Root Hub Status Change interrupt support. In
these controllers the RHSC interrupt bit essentially never turns off,
making RHSC interrupts useless -- they have to remain permanently
disabled.
Such controllers should still be allowed to turn off their root hubs
when no devices are attached. Polling for new connections can
continue while the root hub is suspended. The patch implements this
feature. (It won't have much effect unless CONFIG_PM is enabled and
CONFIG_USB_SUSPEND is disabled, but since the overhead is very small
we may as well do it.)
Alan Stern [Tue, 2 Sep 2008 14:12:11 +0000 (10:12 -0400)]
usb-storage: report underflow with no sense data
This patch (as1118) addresses a problem with certain USB mass-storage
devices. These devices sometimes return less data than asked for and
then provide no sense data to explain the problem. Currently
usb-storage leaves it up to the SCSI layer to decide how this should
be handled, and the SCSI layer interprets the lack of sense data to
mean that nothing went wrong. But if we got less data than required
then something definitely _did_ go wrong, and we should say so.
The patch tells the SCSI layer to retry the command when this sort of
thing happens. Retrying may not solve the underlying problem, but
it's better than believing that data was transferred when it wasn't.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
projects / linux-2.6-omap-h63xx.git / log