- 01 12月, 2008 3 次提交
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由 Christoph Hellwig 提交于
Move all fields from xlog_iclog_fields_t into xlog_in_core_t instead of having them in a substructure and the using #defines to make it look like they were directly in xlog_in_core_t. Also document that xlog_in_core_2_t is grossly misnamed, and make all references to it typesafe. (First sent on Semptember 15th) Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NDave Chinner <david@fromorbit.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com>
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由 From: Christoph Hellwig 提交于
Add a helper to read the AGF header and perform basic verification. Based on hunks from a larger patch from Dave Chinner. (First sent on Juli 23rd) Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NDave Chinner <david@fromorbit.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com>
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由 Christoph Hellwig 提交于
Add a helper to read the AGI header and perform basic verification. Based on hunks from a larger patch from Dave Chinner. (First sent on Juli 23rd) Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NDave Chinner <david@fromorbit.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com>
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- 10 11月, 2008 1 次提交
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由 David Chinner 提交于
When we are about to add a new item to a transaction in recovery, we need to check that it is valid first. Currently we just assert that header magic number matches, but in production systems that is not present and we add a corrupted transaction to the list to be processed. This results in a kernel oops later when processing the corrupted transaction. Instead, if we detect a corrupted transaction, abort recovery and leave the user to clean up the mess that has occurred. SGI-PV: 988145 SGI-Modid: xfs-linux-melb:xfs-kern:32356a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NTim Shimmin <tes@sgi.com> Signed-off-by: NEric Sandeen <sandeen@sandeen.net> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 30 10月, 2008 8 次提交
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由 David Chinner 提交于
When we are about to add a new item to a transaction in recovery, we need to check that it is valid first. Currently we just assert that header magic number matches, but in production systems that is not present and we add a corrupted transaction to the list to be processed. This results in a kernel oops later when processing the corrupted transaction. Instead, if we detect a corrupted transaction, abort recovery and leave the user to clean up the mess that has occurred. SGI-PV: 988145 SGI-Modid: xfs-linux-melb:xfs-kern:32356a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NTim Shimmin <tes@sgi.com> Signed-off-by: NEric Sandeen <sandeen@sandeen.net> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
Change all the remaining AIL API functions that are passed struct xfs_mount pointers to pass pointers directly to the struct xfs_ail being used. With this conversion, all external access to the AIL is via the struct xfs_ail. Hence the operation and referencing of the AIL is almost entirely independent of the xfs_mount that is using it - it is now much more tightly tied to the log and the items it is tracking in the log than it is tied to the xfs_mount. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32353a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 David Chinner 提交于
When we need to go from the log to the AIL, we have to go via the xfs_mount. Add a xfs_ail pointer to the log so we can go directly to the AIL associated with the log. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32351a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 David Chinner 提交于
Bring the ail lock inside the struct xfs_ail. This means the AIL can be entirely manipulated via the struct xfs_ail rather than needing both the struct xfs_mount and the struct xfs_ail. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32350a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 David Chinner 提交于
With the new cursor interface, it makes sense to make all the traversing code use the cursor interface and make the old one go away. This means more of the AIL interfacing is done by passing struct xfs_ail pointers around the place instead of struct xfs_mount pointers. We can replace the use of xfs_trans_first_ail() in xfs_log_need_covered() as it is only checking if the AIL is empty. We can do that with a call to xfs_trans_ail_tail() instead, where a zero LSN returned indicates and empty AIL... SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32348a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 David Chinner 提交于
To replace the current generation number ensuring sanity of the AIL traversal, replace it with an external cursor that is linked to the AIL. Basically, we store the next item in the cursor whenever we want to drop the AIL lock to do something to the current item. When we regain the lock. the current item may already be free, so we can't reference it, but the next item in the traversal is already held in the cursor. When we move or delete an object, we search all the active cursors and if there is an item match we clear the cursor(s) that point to the object. This forces the traversal to restart transparently. We don't invalidate the cursor on insert because the cursor still points to a valid item. If the intem is inserted between the current item and the cursor it does not matter; the traversal is considered to be past the insertion point so it will be picked up in the next traversal. Hence traversal restarts pretty much disappear altogether with this method of traversal, which should substantially reduce the overhead of pushing on a busy AIL. Version 2 o add restart logic o comment cursor interface o minor cleanups SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32347a Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 Christoph Hellwig 提交于
structures. Always use the generic xfs_btree_block type instead of the short / long structures. Add XFS_BTREE_SBLOCK_LEN / XFS_BTREE_LBLOCK_LEN defines for the length of a short / long form block. The rationale for this is that we will grow more btree block header variants to support CRCs and other RAS information, and always accessing them through the same datatype with unions for the short / long form pointers makes implementing this much easier. SGI-PV: 988146 SGI-Modid: xfs-linux-melb:xfs-kern:32300a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NDonald Douwsma <donaldd@sgi.com> Signed-off-by: NDavid Chinner <david@fromorbit.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 Christoph Hellwig 提交于
Clean up the way the maximum and minimum records for the btree blocks are calculated. For the alloc and inobt btrees all the values are pre-calculated in xfs_mount_common, and we switch the current loop around the ugly generic macros that use cpp token pasting to generate type names to two small helpers in normal C code. For the bmbt and bmdr trees these helpers also exist, but can be called during runtime, too. Here we also kill various macros dealing with them and inline the logic into the get_minrecs / get_maxrecs / get_dmaxrecs methods in xfs_bmap_btree.c. Note that all these new helpers take an xfs_mount * argument which will be needed to determine the size of a btree block once we add support for extended btree blocks with CRCs and other RAS information. SGI-PV: 988146 SGI-Modid: xfs-linux-melb:xfs-kern:32292a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NDonald Douwsma <donaldd@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 13 8月, 2008 1 次提交
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由 Christoph Hellwig 提交于
Remove all the useless flags and code keyed off it in xfs_mountfs. SGI-PV: 981498 SGI-Modid: xfs-linux-melb:xfs-kern:31831a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 28 7月, 2008 1 次提交
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由 Denys Vlasenko 提交于
kmem_free() function takes (ptr, size) arguments but doesn't actually use second one. This patch removes size argument from all callsites. SGI-PV: 981498 SGI-Modid: xfs-linux-melb:xfs-kern:31050a Signed-off-by: NDenys Vlasenko <vda.linux@googlemail.com> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 18 4月, 2008 9 次提交
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由 David Chinner 提交于
xfs_buf_associate_memory() can fail, but the return is never checked. Propagate the error through XFS_BUF_SET_PTR() so that failures are detected. SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30831a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
Catch errors from xfs_imap() in log recovery when we might be trying to map an invalid inode number due to a corrupted log. SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30829a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
xfsbdstrat() is declared to return an error. That is never checked because the error is propagated by the xfs_buf_t that is passed through the function. Mark xfsbdstrat() as returning void and comment the prototype on the methods needed for error checking. SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30823a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
xfs_free_extent() can fail, but log recovery never bothers to check if it successfully free the extent it was supposed to. This could lead to silent corruption during log recovery. Abort log recovery if we fail to free an extent. SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30801a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
xfs_trans_commit() can return errors when there are problems in the transaction subsystem. They are indicative that the entire transaction may be incomplete, and hence the error should be propagated as there is a good possibility that there is something fatally wrong in the filesystem. Catch and propagate or warn about commit errors in the places where they are currently ignored. SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30795a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
xfs_trans_reserve() reports errors that should not be ignored. For example, a shutdown filesystem will report errors through xfs_trans_reserve() to prevent further changes from being attempted on a damaged filesystem. Catch and propagate all error conditions from xfs_trans_reserve(). SGI-PV: 980084 SGI-Modid: xfs-linux-melb:xfs-kern:30794a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NNiv Sardi <xaiki@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 Harvey Harrison 提交于
__FUNCTION__ is gcc-specific, use __func__ SGI-PV: 976035 SGI-Modid: xfs-linux-melb:xfs-kern:30775a Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 Christoph Hellwig 提交于
Most VN_RELE calls either directly contain a XFS_ITOV or have the corresponding xfs_inode already in scope. Use the IRELE helper instead of VN_RELE to clarify the code. With a little more work we can kill VN_RELE altogether and define IRELE in terms of iput directly. SGI-PV: 976035 SGI-Modid: xfs-linux-melb:xfs-kern:30710a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
When pdflush is writing back inodes, it can get stuck on inode cluster buffers that are currently under I/O. This occurs when we write data to multiple inodes in the same inode cluster at the same time. Effectively, delayed allocation marks the inode dirty during the data writeback. Hence if the inode cluster was flushed during the writeback of the first inode, the writeback of the second inode will block waiting for the inode cluster write to complete before writing it again for the newly dirtied inode. Basically, we want to avoid this from happening so we don't block pdflush and slow down all of writeback. Hence we introduce a non-blocking async inode flush flag that pdflush uses. If this flag is set, we use non-blocking operations (e.g. try locks) whereever we can to avoid blocking or extra I/O being issued. SGI-PV: 970925 SGI-Modid: xfs-linux-melb:xfs-kern:30501a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 10 4月, 2008 1 次提交
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由 Eric Sandeen 提交于
Remove macro-to-small-function indirection from xfs_sb.h, and remove some which are completely unused. SGI-PV: 976035 SGI-Modid: xfs-linux-melb:xfs-kern:30528a Signed-off-by: NEric Sandeen <sandeen@sandeen.net> Signed-off-by: NDonald Douwsma <donaldd@sgi.com> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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- 07 2月, 2008 7 次提交
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由 Lachlan McIlroy 提交于
A problem was reported where a system panicked in log recovery due to a corrupt log record. The cause of the corruption is not known but this change will at least prevent a crash for this specific scenario. Log recovery definitely needs some more work in this area. SGI-PV: 974151 SGI-Modid: xfs-linux-melb:xfs-kern:30318a Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org>
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由 David Chinner 提交于
Sparse trips over the locking order in xlog_recover_do_efd_trans() when xfs_trans_delete_ail() drops the ail lock. Because the unlock is conditional, we need to either annotate with a "fake unlock" or change the structure of the code so sparse thinks the function always unlocks. Reordering the code makes it simpler, so do that. SGI-PV: 972755 SGI-Modid: xfs-linux-melb:xfs-kern:30003a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 David Chinner 提交于
These are mostly locking annotations, marking things static, casts where needed and declaring stuff in header files. SGI-PV: 971186 SGI-Modid: xfs-linux-melb:xfs-kern:30002a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
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由 Christoph Hellwig 提交于
Mostly trivial conversion with one exceptions: h_num_logops was kept in native endian previously and only converted to big endian in xlog_sync, but we always keep it big endian now. With todays cpus fast byteswap instructions that's not an issue but the new variant keeps the code clean and maintainable. SGI-PV: 971186 SGI-Modid: xfs-linux-melb:xfs-kern:29821a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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由 Christoph Hellwig 提交于
- the various assign lsn macros are replaced by a single inline, xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except for a more sane calling convention. ASSIGN_LSN_DISK is replaced by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same, except we pass the cycle and block arguments explicitly instead of a log paramter. The latter two variants only had 2, respectively one user anyway. - the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the same calling conventions. - GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away the unused arch argument. Instead of conditional defintions depending on host endianess we now do an unconditional swap and shift then, which generates equal code. - the unused XLOG_SET macro is removed. SGI-PV: 971186 SGI-Modid: xfs-linux-melb:xfs-kern:29820a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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由 Christoph Hellwig 提交于
- the various assign lsn macros are replaced by a single inline, xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except for a more sane calling convention. ASSIGN_LSN_DISK is replaced by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same, except we pass the cycle and block arguments explicitly instead of a log paramter. The latter two variants only had 2, respectively one user anyway. - the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the same calling conventions. - GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away the unused arch argument. Instead of conditional defintions depending on host endianess we now do an unconditional swap and shift then, which generates equal code. - the unused XLOG_SET macro is removed. SGI-PV: 971186 SGI-Modid: xfs-linux-melb:xfs-kern:29819a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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由 Donald Douwsma 提交于
SGI-PV: 970382 SGI-Modid: xfs-linux-melb:xfs-kern:29739a Signed-off-by: NDonald Douwsma <donaldd@sgi.com> Signed-off-by: NEric Sandeen <sandeen@sandeen.net> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 16 10月, 2007 1 次提交
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由 Lachlan McIlroy 提交于
SGI-PV: 971603 SGI-Modid: xfs-linux-melb:xfs-kern:29871a Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 15 10月, 2007 2 次提交
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由 Christoph Hellwig 提交于
Creates a new xfs_dsb_t that is __be annotated and keeps xfs_sb_t for the incore one. xfs_xlatesb is renamed to xfs_sb_to_disk and only handles the incore -> disk conversion. A new helper xfs_sb_from_disk handles the other direction and doesn't need the slightly hacky table-driven approach because we only ever read the full sb from disk. The handling of shared r/o filesystems has been buggy on little endian system and fixing this required shuffling around of some code in that area. SGI-PV: 968563 SGI-Modid: xfs-linux-melb:xfs-kern:29477a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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由 Christoph Hellwig 提交于
Biggest bit is duplicating the dinode structure so we have one annotated for native endianess and one for disk endianess. The other significant change is that xfs_xlate_dinode_core is split into one helper per direction to allow for proper annotations, everything else is trivial. As a sidenode splitting out the incore dinode means we can move it into xfs_inode.h in a later patch and severely improving on the include hell in xfs. SGI-PV: 968563 SGI-Modid: xfs-linux-melb:xfs-kern:29476a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 01 10月, 2007 2 次提交
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由 Tim Shimmin 提交于
This reverts commit b394e43e. Lachlan McIlroy says: It tried to fix an issue where log replay is replaying an inode cluster initialisation transaction that should not be replayed because the inode cluster on disk is more up to date. Since we don't log file sizes (we rely on inode flushing to get them to disk) then we can't just replay all the transations in the log and expect the inode to be completely restored. We lose file size updates. Unfortunately this fix is causing more (serious) problems than it is fixing. SGI-PV: 969656 SGI-Modid: xfs-linux-melb:xfs-kern:29804a Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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由 Tim Shimmin 提交于
This reverts commit b394e43e. SGI-PV: 969656 SGI-Modid: xfs-linux-melb:xfs-kern:29804a Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 20 9月, 2007 1 次提交
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由 Christoph Hellwig 提交于
The new xlog_recover_do_reg_buffer checks call be16_to_cpu on di_gen which is a 32bit value so sparse rightly complains. Fortunately the warning is harmless because we don't care for the value, but only whether it's non-NULL. Due to that fact we can simply kill the endian swaps on this and the previous di_mode check entirely. SGI-PV: 969656 SGI-Modid: xfs-linux-melb:xfs-kern:29709a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 18 9月, 2007 1 次提交
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由 Lachlan McIlroy 提交于
SGI-PV: 969656 SGI-Modid: xfs-linux-melb:xfs-kern:29676a Signed-off-by: NLachlan McIlroy <lachlan@sgi.com> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 05 9月, 2007 1 次提交
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由 Christoph Hellwig 提交于
Sparse now warns about comparing pointers to 0, so change all instance where that happens to NULL instead. SGI-PV: 968555 SGI-Modid: xfs-linux-melb:xfs-kern:29308a Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NTim Shimmin <tes@sgi.com>
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- 14 7月, 2007 1 次提交
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由 David Chinner 提交于
When we have a couple of hundred transactions on the fly at once, they all typically modify the on disk superblock in some way. create/unclink/mkdir/rmdir modify inode counts, allocation/freeing modify free block counts. When these counts are modified in a transaction, they must eventually lock the superblock buffer and apply the mods. The buffer then remains locked until the transaction is committed into the incore log buffer. The result of this is that with enough transactions on the fly the incore superblock buffer becomes a bottleneck. The result of contention on the incore superblock buffer is that transaction rates fall - the more pressure that is put on the superblock buffer, the slower things go. The key to removing the contention is to not require the superblock fields in question to be locked. We do that by not marking the superblock dirty in the transaction. IOWs, we modify the incore superblock but do not modify the cached superblock buffer. In short, we do not log superblock modifications to critical fields in the superblock on every transaction. In fact we only do it just before we write the superblock to disk every sync period or just before unmount. This creates an interesting problem - if we don't log or write out the fields in every transaction, then how do the values get recovered after a crash? the answer is simple - we keep enough duplicate, logged information in other structures that we can reconstruct the correct count after log recovery has been performed. It is the AGF and AGI structures that contain the duplicate information; after recovery, we walk every AGI and AGF and sum their individual counters to get the correct value, and we do a transaction into the log to correct them. An optimisation of this is that if we have a clean unmount record, we know the value in the superblock is correct, so we can avoid the summation walk under normal conditions and so mount/recovery times do not change under normal operation. One wrinkle that was discovered during development was that the blocks used in the freespace btrees are never accounted for in the AGF counters. This was once a valid optimisation to make; when the filesystem is full, the free space btrees are empty and consume no space. Hence when it matters, the "accounting" is correct. But that means the when we do the AGF summations, we would not have a correct count and xfs_check would complain. Hence a new counter was added to track the number of blocks used by the free space btrees. This is an *on-disk format change*. As a result of this, lazy superblock counters are a mkfs option and at the moment on linux there is no way to convert an old filesystem. This is possible - xfs_db can be used to twiddle the right bits and then xfs_repair will do the format conversion for you. Similarly, you can convert backwards as well. At some point we'll add functionality to xfs_admin to do the bit twiddling easily.... SGI-PV: 964999 SGI-Modid: xfs-linux-melb:xfs-kern:28652a Signed-off-by: NDavid Chinner <dgc@sgi.com> Signed-off-by: NChristoph Hellwig <hch@infradead.org> Signed-off-by: NTim Shimmin <tes@sgi.com>
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