linux/fs/ubifs, branch v2.6.39-rc2

fs: export empty_aops

2011-04-05T21:51:48Z

With the ->sync_page() hook gone, we have a few users that add their own static address_space_operations without any functions defined. fs/inode.c already has an empty_aops that it uses for init purposes. Lets export that and use it in the places where an otherwise empty aops was defined. Signed-off-by: Jens Axboe

Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block

2011-03-24T17:16:26Z

* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits) Documentation/iostats.txt: bit-size reference etc. cfq-iosched: removing unnecessary think time checking cfq-iosched: Don't clear queue stats when preempt. blk-throttle: Reset group slice when limits are changed blk-cgroup: Only give unaccounted_time under debug cfq-iosched: Don't set active queue in preempt block: fix non-atomic access to genhd inflight structures block: attempt to merge with existing requests on plug flush block: NULL dereference on error path in __blkdev_get() cfq-iosched: Don't update group weights when on service tree fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away block: Require subsystems to explicitly allocate bio_set integrity mempool jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging fs: make fsync_buffers_list() plug mm: make generic_writepages() use plugging blk-cgroup: Add unaccounted time to timeslice_used. block: fixup plugging stubs for !CONFIG_BLOCK block: remove obsolete comments for blkdev_issue_zeroout. blktrace: Use rq->cmd_flags directly in blk_add_trace_rq. ... Fix up conflicts in fs/{aio.c,super.c}

Merge branch 'for-linus' of git://git.infradead.org/ubi-2.6

2011-03-24T15:22:34Z

* 'for-linus' of git://git.infradead.org/ubi-2.6: UBIFS: fix assertion warning and refine comments UBIFS: kill CONFIG_UBIFS_FS_DEBUG_CHKS UBIFS: use GFP_NOFS properly UBI: use GFP_NOFS properly

UBIFS: fix assertion warning and refine comments

2011-03-24T14:16:18Z

This patch fixes the following UBIFS assertion warning: UBIFS assert failed in do_readpage at 115 (pid 199) [] (unwind_backtrace+0x0/0xdc) from [] (do_readpage+0x108/0x594 [ubifs]) [] (do_readpage+0x108/0x594 [ubifs]) from [] (ubifs_write_end+0x1c0/0x2e8 [ubifs]) [] (ubifs_write_end+0x1c0/0x2e8 [ubifs]) from [] (generic_file_buffered_write+0x18c/0x270) [] (generic_file_buffered_write+0x18c/0x270) from [] (__generic_file_aio_write+0x478/0x4c0) [] (__generic_file_aio_write+0x478/0x4c0) from [] (generic_file_aio_write+0x68/0xc8) [] (generic_file_aio_write+0x68/0xc8) from [] (ubifs_aio_write+0x178/0x1d8 [ubifs]) [] (ubifs_aio_write+0x178/0x1d8 [ubifs]) from [] (do_sync_write+0xb0/0x100) [] (do_sync_write+0xb0/0x100) from [] (vfs_write+0xac/0x154) [] (vfs_write+0xac/0x154) from [] (sys_write+0x3c/0x68) [] (sys_write+0x3c/0x68) from [] (ret_fast_syscall+0x0/0x2c) The 'PG_checked' flag is used to indicate that the page does not supposedly exist on the media (e.g., a hole or a page beyond the inode size), so it requires slightly bigger budget, because we have to account the indexing size increase. And this flag basically tells that the budget for this page has to be "new page budget". The "new page budget" is slightly bigger than the "existing page budget". The 'do_readpage()' function has the following assertion which sometimes is hit: 'ubifs_assert(!PageChecked(page))'. Obviously, the meaning of this assertion is: "I should not be asked to read a page which does not exist on the media". However, in 'ubifs_write_begin()' we have a small "trick". Notice, that VFS may write pages which were not read yet, so the page data were not loaded from the media to the page cache yet. If VFS tells that it is going to change only some part of the page, we obviously have to load it from the media. However, if VFS tells that it is going to change whole page, we do not read it from the media for optimization purposes. However, since we do not read it, we do not know if it exists on the media or not (a hole, etc). So we set the 'PG_checked' flag to this page to force bigger budget, just in case. So 'ubifs_write_begin()' sets 'PG_checked'. Then we are in 'ubifs_write_end()'. And VFS tells us: "hey, for some reasons I changed my mind and did not change whole page". Frankly, I do not know why this happens, but I hit this somehow on an ARM platform. And this is extremely rare. So in this case UBIFS does the following: 1. Cancels allocated budget. 2. Loads the page from the media by calling 'do_readpage()'. 3. Asks VFS to repeat the whole write operation from the very beginning (call '->write_begin() again, etc). And the assertion warning is hit at the step 2 - remember we have the 'PG_checked' set for this page, and 'do_readpage()' does not like this. So this patch fixes the problem by adding step 1.5 and cleaning the 'PG_checked' before calling 'do_readpage()'. All in all, this patch does not fix any functionality issue, but it silences UBIFS false positive warning which may happen in very very rare cases. And while on it, this patch also improves a commentary which explains the reasons of setting the 'PG_checked' flag for the page. The old commentary was a bit difficult to understand. Signed-off-by: Artem Bityutskiy

UBIFS: kill CONFIG_UBIFS_FS_DEBUG_CHKS

2011-03-24T14:16:08Z

Simplify UBIFS configuration menu and kill the option to enable self-check compile-time. We do not really need this because we can do this run-time using the module parameters or the corresponding sysfs interfaces. And there is a value in simplifying the kernel configuration menu which becomes increasingly large. Signed-off-by: Artem Bityutskiy

UBIFS: use GFP_NOFS properly

2011-03-24T14:14:26Z

This patch fixes a brown-paperbag bug which was introduced by me: I used incorrect "GFP_KERNEL | GFP_NOFS" allocation flags to make sure my allocations do not cause write-back. But the correct form is "GFP_NOFS". Signed-off-by: Artem Bityutskiy

userns: rename is_owner_or_cap to inode_owner_or_capable

2011-03-24T02:47:13Z

And give it a kernel-doc comment. [akpm@linux-foundation.org: btrfs changed in linux-next] Signed-off-by: Serge E. Hallyn Cc: "Eric W. Biederman" Cc: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6

2011-03-18T17:50:27Z

* 'linux-next' of git://git.infradead.org/ubifs-2.6: (25 commits) UBIFS: clean-up commentaries UBIFS: save 128KiB or more RAM UBIFS: allocate orphans scan buffer on demand UBIFS: allocate lpt dump buffer on demand UBIFS: allocate ltab checking buffer on demand UBIFS: allocate scanning buffer on demand UBIFS: allocate dump buffer on demand UBIFS: do not check data crc by default UBIFS: simplify UBIFS Kconfig menu UBIFS: print max. index node size UBIFS: handle allocation failures in UBIFS write path UBIFS: use max_write_size during recovery UBIFS: use max_write_size for write-buffers UBIFS: introduce write-buffer size field UBI: incorporate LEB offset information UBIFS: incorporate maximum write size UBI: provide LEB offset information UBI: incorporate maximum write size UBIFS: fix LEB number in printk UBIFS: restrict world-writable debugfs files ...

UBIFS: clean-up commentaries

2011-03-16T12:05:25Z

Clean-up commentaries in debug.h and remove references to non-existing symblols. Signed-off-by: Artem Bityutskiy

UBIFS: save 128KiB or more RAM

2011-03-16T12:05:25Z

When debugging is enabled, we allocate a buffer of PEB size for various debugging purposes. However, now all users of this buffer are gone and we can safely remove it and save 128KiB or more RAM. Signed-off-by: Artem Bityutskiy