- 05 May, 2017 1 commit
-
-
Eryu Guan authored
Commit 28b783e4 ("xfs: bufferhead chains are invalid after end_page_writeback") fixed one use-after-free issue by pre-calculating the loop conditionals before calling bh->b_end_io() in the end_io processing loop, but it assigned 'next' pointer before checking end offset boundary & breaking the loop, at which point the bh might be freed already, and caused use-after-free. This is caught by KASAN when running fstests generic/127 on sub-page block size XFS. [ 2517.244502] run fstests generic/127 at 2017-04-27 07:30:50 [ 2747.868840] ================================================================== [ 2747.876949] BUG: KASAN: use-after-free in xfs_destroy_ioend+0x3d3/0x4e0 [xfs] at addr ffff8801395ae698 ... [ 2747.918245] Call Trace: [ 2747.920975] dump_stack+0x63/0x84 [ 2747.924673] kasan_object_err+0x21/0x70 [ 2747.928950] kasan_report+0x271/0x530 [ 2747.933064] ? xfs_destroy_ioend+0x3d3/0x4e0 [xfs] [ 2747.938409] ? end_page_writeback+0xce/0x110 [ 2747.943171] __asan_report_load8_noabort+0x19/0x20 [ 2747.948545] xfs_destroy_ioend+0x3d3/0x4e0 [xfs] [ 2747.953724] xfs_end_io+0x1af/0x2b0 [xfs] [ 2747.958197] process_one_work+0x5ff/0x1000 [ 2747.962766] worker_thread+0xe4/0x10e0 [ 2747.966946] kthread+0x2d3/0x3d0 [ 2747.970546] ? process_one_work+0x1000/0x1000 [ 2747.975405] ? kthread_create_on_node+0xc0/0xc0 [ 2747.980457] ? syscall_return_slowpath+0xe6/0x140 [ 2747.985706] ? do_page_fault+0x30/0x80 [ 2747.989887] ret_from_fork+0x2c/0x40 [ 2747.993874] Object at ffff8801395ae690, in cache buffer_head size: 104 [ 2748.001155] Allocated: [ 2748.003782] PID = 8327 [ 2748.006411] save_stack_trace+0x1b/0x20 [ 2748.010688] save_stack+0x46/0xd0 [ 2748.014383] kasan_kmalloc+0xad/0xe0 [ 2748.018370] kasan_slab_alloc+0x12/0x20 [ 2748.022648] kmem_cache_alloc+0xb8/0x1b0 [ 2748.027024] alloc_buffer_head+0x22/0xc0 [ 2748.031399] alloc_page_buffers+0xd1/0x250 [ 2748.035968] create_empty_buffers+0x30/0x410 [ 2748.040730] create_page_buffers+0x120/0x1b0 [ 2748.045493] __block_write_begin_int+0x17a/0x1800 [ 2748.050740] iomap_write_begin+0x100/0x2f0 [ 2748.055308] iomap_zero_range_actor+0x253/0x5c0 [ 2748.060362] iomap_apply+0x157/0x270 [ 2748.064347] iomap_zero_range+0x5a/0x80 [ 2748.068624] iomap_truncate_page+0x6b/0xa0 [ 2748.073227] xfs_setattr_size+0x1f7/0xa10 [xfs] [ 2748.078312] xfs_vn_setattr_size+0x68/0x140 [xfs] [ 2748.083589] xfs_file_fallocate+0x4ac/0x820 [xfs] [ 2748.088838] vfs_fallocate+0x2cf/0x780 [ 2748.093021] SyS_fallocate+0x48/0x80 [ 2748.097006] do_syscall_64+0x18a/0x430 [ 2748.101186] return_from_SYSCALL_64+0x0/0x6a [ 2748.105948] Freed: [ 2748.108189] PID = 8327 [ 2748.110816] save_stack_trace+0x1b/0x20 [ 2748.115093] save_stack+0x46/0xd0 [ 2748.118788] kasan_slab_free+0x73/0xc0 [ 2748.122969] kmem_cache_free+0x7a/0x200 [ 2748.127247] free_buffer_head+0x41/0x80 [ 2748.131524] try_to_free_buffers+0x178/0x250 [ 2748.136316] xfs_vm_releasepage+0x2e9/0x3d0 [xfs] [ 2748.141563] try_to_release_page+0x100/0x180 [ 2748.146325] invalidate_inode_pages2_range+0x7da/0xcf0 [ 2748.152087] xfs_shift_file_space+0x37d/0x6e0 [xfs] [ 2748.157557] xfs_collapse_file_space+0x49/0x120 [xfs] [ 2748.163223] xfs_file_fallocate+0x2a7/0x820 [xfs] [ 2748.168462] vfs_fallocate+0x2cf/0x780 [ 2748.172642] SyS_fallocate+0x48/0x80 [ 2748.176629] do_syscall_64+0x18a/0x430 [ 2748.180810] return_from_SYSCALL_64+0x0/0x6a Fixed it by checking on offset against end & breaking out first, dereference bh only if there're still bufferheads to process. Signed-off-by: Eryu Guan <eguan@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
- 03 May, 2017 1 commit
-
-
Darrick J. Wong authored
In xfs_reflink_end_cow, we erroneously reserve only enough blocks to handle adding 1 extent. This is problematic if we fragment free space, have to do CoW, and then have to perform multiple bmap btree expansions. Furthermore, the BUI recovery routine doesn't reserve /any/ blocks to handle btree splits, so log recovery fails after our first error causes the filesystem to go down. Therefore, refactor the transaction block reservation macros until we have a macro that works for our deferred (re)mapping activities, and fix both problems by using that macro. With 1k blocks we can hit this fairly often in g/187 if the scratch fs is big enough. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
-
- 28 Apr, 2017 4 commits
-
-
Brian Foster authored
The quotaoff operation has a race with inode allocation that results in a livelock. An inode allocation that occurs before the quota status flags are updated acquires the appropriate dquots for the inode via xfs_qm_vop_dqalloc(). It then inserts the XFS_INEW inode into the perag radix tree, sometime later attaches the dquots to the inode and finally clears the XFS_INEW flag. Quotaoff expects to release the dquots from all inodes in the filesystem via xfs_qm_dqrele_all_inodes(). This invokes the AG inode iterator, which skips inodes in the XFS_INEW state because they are not fully constructed. If the scan occurs after dquots have been attached to an inode, but before XFS_INEW is cleared, the newly allocated inode will continue to hold a reference to the applicable dquots. When quotaoff invokes xfs_qm_dqpurge_all(), the reference count of those dquot(s) remain elevated and the dqpurge scan spins indefinitely. To address this problem, update the xfs_qm_dqrele_all_inodes() scan to wait on inodes marked on the XFS_INEW state. We wait on the inodes explicitly rather than skip and retry to avoid continuous retry loops due to a parallel inode allocation workload. Since quotaoff updates the quota state flags and uses a synchronous transaction before the dqrele scan, and dquots are attached to inodes after radix tree insertion iff quota is enabled, one INEW waiting pass through the AG guarantees that the scan has processed all inodes that could possibly hold dquot references. Reported-by: Eryu Guan <eguan@redhat.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Brian Foster authored
The AG inode iterator currently skips new inodes as such inodes are inserted into the inode radix tree before they are fully constructed. Certain contexts require the ability to wait on the construction of new inodes, however. The fs-wide dquot release from the quotaoff sequence is an example of this. Update the AG inode iterator to support the ability to wait on inodes flagged with XFS_INEW upon request. Create a new xfs_inode_ag_iterator_flags() interface and support a set of iteration flags to modify the iteration behavior. When the XFS_AGITER_INEW_WAIT flag is set, include XFS_INEW flags in the radix tree inode lookup and wait on them before the callback is executed. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Brian Foster authored
Inodes that are inserted into the perag tree but still under construction are flagged with the XFS_INEW bit. Most contexts either skip such inodes when they are encountered or have the ability to handle them. The runtime quotaoff sequence introduces a context that must wait for construction of such inodes to correctly ensure that all dquots in the fs are released. In anticipation of this, support the ability to wait on new inodes. Wake the appropriate bit when XFS_INEW is cleared. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Amir Goldstein authored
Copy the uuid of the filesystem to struct super_block s_uuid field, as several other filesystems already do. Copy regardless of the nouuid mount option, because other filesystems also do not guaranty uniqueness of the s_uuid field in super_block struct. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
- 27 Apr, 2017 1 commit
-
-
Lukas Czerner authored
fstrim can take really long time on big, slow device or on file system with a lots of allocation groups. Currently there is no way for the user to cancell the operation. This patch makes it possible for the user to kill fstrim pocess by adding the check for fatal_signal_pending() in xfs_trim_extents(). Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
- 25 Apr, 2017 24 commits
-
-
Darrick J. Wong authored
Use ASSERTs on the log intent item refcounts so that we fail noisily if anyone tries to double-free the item. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
-
Brian Foster authored
The quotacheck error handling of the delwri buffer list assumes the resident buffers are locked and doesn't clear the _XBF_DELWRI_Q flag on the buffers that are dequeued. This can lead to assert failures on buffer release and possibly other locking problems. Move this code to a delwri queue cancel helper function to encapsulate the logic required to properly release buffers from a delwri queue. Update the helper to clear the delwri queue flag and call it from quotacheck. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
xfs_iflush_done uses an on-stack variable length array to pass the log items to be deleted to xfs_trans_ail_delete_bulk. On-stack VLAs are a nasty gcc extension that can lead to unbounded stack allocations, but fortunately we can easily avoid them by simply open coding xfs_trans_ail_delete_bulk in xfs_iflush_done, which is the only caller of it except for the single-item xfs_trans_ail_delete. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Using bool values produces sparse warnings of this form: fs/xfs/./xfs_trace.h:2252:1: warning: odd constant _Bool cast (ffffffffffffffff becomes 1) fs/xfs/./xfs_trace.h:2252:1: warning: odd constant _Bool cast (ffffffffffffffff becomes 1) fs/xfs/./xfs_trace.h:2278:1: warning: odd constant _Bool cast (ffffffffffffffff becomes 1) fs/xfs/./xfs_trace.h:2278:1: warning: odd constant _Bool cast (ffffffffffffffff becomes 1) fs/xfs/./xfs_trace.h:2307:1: warning: odd constant _Bool cast (ffffffffffffffff becomes 1) Just use a char instead to fix those up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Darrick J. Wong authored
At the end of a getfsmap call, we will set FMR_OF_LAST in the last struct fsmap that was handed in by userspace if we've truly run out of space mapping record (as opposed to simply running out of space in the user array). Unfortunately, fmh_entries is the wrong check for whether or not we've filled out anything in the user array because the ioctl provides that fmh_count==0 sets fmh_entries without filling out the user array. Therefore we end up writing things into user memory areas that we weren't given, and kaboom. Since Christoph amended the getfsmap structure to track the number of fsmap entries we've actually filled out, use that as part of deciding if we have to set the OF_LAST flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
-
Christoph Hellwig authored
By passing the whole fsmap_head structure and an index we can get the user point annotations right for the embedded variable sized array in struct fsmap_head. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: change idx to unsigned int] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
At least if we want to be able to recognize the pattern. Add a missing byte swap to the corruption injection case in xlog_sync. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Found by sparse. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Found by sparse. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
XFS only supports the unwritten extent bit in the data fork, and only if the file system has a version 5 superblock or the unwritten extent feature bit. We currently have two routines that validate the invariant: xfs_check_nostate_extents which return -EFSCORRUPTED when it's not met, and xfs_validate_extent that triggers and assert in debug build. Both of them iterate over all extents of an inode fork when called, which isn't very efficient. This patch instead adds a new helper that verifies the invariant one extent at a time, and calls it from the places where we iterate over all extents to converted them from or two the in-memory format. The callers then return -EFSCORRUPTED when reading invalid extents from disk, or trigger an assert when writing them to disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
We only ever use the normal and unwritten states. And the actual ondisk format (this enum isn't despite being in xfs_format.h) only has space for the unwritten bit anyway. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Eric Sandeen authored
On some architectures do_div does the pointer compare trick to make sure that we've sent it an unsigned 64-bit number. (Why unsigned? I don't know.) Fix up the few places that squawk about this; in xfs_bmap_wants_extents() we just used a bare int64_t so change that to unsigned. In xfs_adjust_extent_unmap_boundaries() all we wanted was the mod, and we have an xfs-specific function to handle that w/o side effects, which includes proper casting for do_div. In xfs_daddr_to_ag[b]no, we were using the wrong type anyway; XFS_BB_TO_FSBT returns a block in the filesystem, so use xfs_rfsblock_t not xfs_daddr_t, and gain the unsignedness from that type as a bonus. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Eric Sandeen authored
The kbuild test robot caught this; in debug code we have another caller of do_div with a 32-bit dividend (j) which is caught now that we are using the kernel-supplied do_div. None of the values used here are 64-bit; just use simple division. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Hou Tao authored
The trailing newlines wil lead to extra newlines in the trace file which looks like the following output, so remove them. >kworker/4:1H-1508 [004] .... 47879.101608: xfs_discard_extent: dev 8:0 > >kworker/u16:2-238 [004] .... 47879.101725: xfs_extent_busy_clear: dev 8:0 Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: fix the getfsmap tracepoints too] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Brian Foster authored
Directory block readahead uses a complex iteration mechanism to map between high-level directory blocks and underlying physical extents. This mechanism attempts to traverse the higher-level dir blocks in a manner that handles multi-fsb directory blocks and simultaneously maintains a reference to the corresponding physical blocks. This logic doesn't handle certain (discontiguous) physical extent layouts correctly with multi-fsb directory blocks. For example, consider the case of a 4k FSB filesystem with a 2 FSB (8k) directory block size and a directory with the following extent layout: EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL 0: [0..7]: 88..95 0 (88..95) 8 1: [8..15]: 80..87 0 (80..87) 8 2: [16..39]: 168..191 0 (168..191) 24 3: [40..63]: 5242952..5242975 1 (72..95) 24 Directory block 0 spans physical extents 0 and 1, dirblk 1 lies entirely within extent 2 and dirblk 2 spans extents 2 and 3. Because extent 2 is larger than the directory block size, the readahead code erroneously assumes the block is contiguous and issues a readahead based on the physical mapping of the first fsb of the dirblk. This results in read verifier failure and a spurious corruption or crc failure, depending on the filesystem format. Further, the subsequent readahead code responsible for walking through the physical table doesn't correctly advance the physical block reference for dirblk 2. Instead of advancing two physical filesystem blocks, the first iteration of the loop advances 1 block (correctly), but the subsequent iteration advances 2 more physical blocks because the next physical extent (extent 3, above) happens to cover more than dirblk 2. At this point, the higher-level directory block walking is completely off the rails of the actual physical layout of the directory for the respective mapping table. Update the contiguous dirblock logic to consider the current offset in the physical extent to avoid issuing directory readahead to unrelated blocks. Also, update the mapping table advancing code to consider the current offset within the current dirblock to avoid advancing the mapping reference too far beyond the dirblock. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Eric Sandeen authored
Carlos had a case where "find" seemed to start spinning forever and never return. This was on a filesystem with non-default multi-fsb (8k) directory blocks, and a fragmented directory with extents like this: 0:[0,133646,2,0] 1:[2,195888,1,0] 2:[3,195890,1,0] 3:[4,195892,1,0] 4:[5,195894,1,0] 5:[6,195896,1,0] 6:[7,195898,1,0] 7:[8,195900,1,0] 8:[9,195902,1,0] 9:[10,195908,1,0] 10:[11,195910,1,0] 11:[12,195912,1,0] 12:[13,195914,1,0] ... i.e. the first extent is a contiguous 2-fsb dir block, but after that it is fragmented into 1 block extents. At the top of the readdir path, we allocate a mapping array which (for this filesystem geometry) can hold 10 extents; see the assignment to map_info->map_size. During readdir, we are therefore able to map extents 0 through 9 above into the array for readahead purposes. If we count by 2, we see that the last mapped index (9) is the first block of a 2-fsb directory block. At the end of xfs_dir2_leaf_readbuf() we have 2 loops to fill more readahead; the outer loop assumes one full dir block is processed each loop iteration, and an inner loop that ensures that this is so by advancing to the next extent until a full directory block is mapped. The problem is that this inner loop may step past the last extent in the mapping array as it tries to reach the end of the directory block. This will read garbage for the extent length, and as a result the loop control variable 'j' may become corrupted and never fail the loop conditional. The number of valid mappings we have in our array is stored in map->map_valid, so stop this inner loop based on that limit. There is an ASSERT at the top of the outer loop for this same condition, but we never made it out of the inner loop, so the ASSERT never fired. Huge appreciation for Carlos for debugging and isolating the problem. Debugged-and-analyzed-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Tested-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Chandan Rajendra authored
On a ppc64 machine executing overlayfs/019 with xfs as the lower and upper filesystem causes the following call trace, WARNING: CPU: 2 PID: 8034 at /root/repos/linux/fs/iomap.c:765 .iomap_dio_actor+0xcc/0x420 Modules linked in: CPU: 2 PID: 8034 Comm: fsstress Tainted: G L 4.11.0-rc5-next-20170405 #100 task: c000000631314880 task.stack: c0000003915d4000 NIP: c00000000035a72c LR: c00000000035a6f4 CTR: c00000000035a660 REGS: c0000003915d7570 TRAP: 0700 Tainted: G L (4.11.0-rc5-next-20170405) MSR: 800000000282b032 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI> CR: 24004284 XER: 00000000 CFAR: c0000000006f7190 SOFTE: 1 GPR00: c00000000035a6f4 c0000003915d77f0 c0000000015a3f00 000000007c22f600 GPR04: 000000000022d000 0000000000002600 c0000003b2d56360 c0000003915d7960 GPR08: c0000003915d7cd0 0000000000000002 0000000000002600 c000000000521cc0 GPR12: 0000000024004284 c00000000fd80a00 000000004b04ae64 ffffffffffffffff GPR16: 000000001000ca70 0000000000000000 c0000003b2d56380 c00000000153d2b8 GPR20: 0000000000000010 c0000003bc87bac8 0000000000223000 000000000022f5ff GPR24: c0000003b2d56360 000000000000000c 0000000000002600 000000000022d000 GPR28: 0000000000000000 c0000003915d7960 c0000003b2d56360 00000000000001ff NIP [c00000000035a72c] .iomap_dio_actor+0xcc/0x420 LR [c00000000035a6f4] .iomap_dio_actor+0x94/0x420 Call Trace: [c0000003915d77f0] [c00000000035a6f4] .iomap_dio_actor+0x94/0x420 (unreliable) [c0000003915d78f0] [c00000000035b9f4] .iomap_apply+0xf4/0x1f0 [c0000003915d79d0] [c00000000035c320] .iomap_dio_rw+0x230/0x420 [c0000003915d7ae0] [c000000000512a14] .xfs_file_dio_aio_read+0x84/0x160 [c0000003915d7b80] [c000000000512d24] .xfs_file_read_iter+0x104/0x130 [c0000003915d7c10] [c0000000002d6234] .__vfs_read+0x114/0x1a0 [c0000003915d7cf0] [c0000000002d7a8c] .vfs_read+0xac/0x1a0 [c0000003915d7d90] [c0000000002d96b8] .SyS_read+0x58/0x100 [c0000003915d7e30] [c00000000000b8e0] system_call+0x38/0xfc Instruction dump: 78630020 7f831b78 7ffc07b4 7c7ce039 40820360 a13d0018 2f890003 419e0288 2f890004 419e00a0 2f890001 419e02a8 <0fe00000> 3b80fffb 38210100 7f83e378 The above problem can also be recreated on a regular xfs filesystem using the command, $ fsstress -d /mnt -l 1000 -n 1000 -p 1000 The reason for the call trace is, 1. When 'reserving' blocks for delayed allocation , XFS reserves more blocks (i.e. past file's current EOF) than required. This is done because XFS assumes that userspace might write more data and hence 'reserving' more blocks might lead to the file's new data being stored contiguously on disk. 2. The in-memory 'struct xfs_bmbt_irec' mapping the file's last extent would then cover the prealloc-ed EOF blocks in addition to the regular blocks. 3. When flushing the dirty blocks to disk, we only flush data till the file's EOF. But before writing out the dirty data, we allocate blocks on the disk for holding the file's new data. This allocation includes the blocks that are part of the 'prealloc EOF blocks'. 4. Later, when the last reference to the inode is being closed, XFS frees the unused 'prealloc EOF blocks' in xfs_inactive(). In step 3 above, When allocating space on disk for the delayed allocation range, the space allocator might sometimes allocate less blocks than required. If such an allocation ends right at the current EOF of the file, We will not be able to clear the "delayed allocation" flag for the 'prealloc EOF blocks', since we won't have dirty buffer heads associated with that range of the file. In such a situation if a Direct I/O read operation is performed on file range [X, Y] (where X < EOF and Y > EOF), we flush dirty data in the range [X, Y] and invalidate page cache for that range (Refer to iomap_dio_rw()). Later for performing the Direct I/O read, XFS obtains the extent items (which are still cached in memory) for the file range. When doing so we are not supposed to get an extent item with IOMAP_DELALLOC flag set, since the previous "flush" operation should have converted any delayed allocation data in the range [X, Y]. Hence we end up hitting a WARN_ON_ONCE(1) statement in iomap_dio_actor(). This commit fixes the bug by preventing the read operation from going beyond iomap_dio->i_size. Reported-by: Santhosh G <santhog4@linux.vnet.ibm.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Now that reflink operations don't set the firstblock value we don't need the workarounds for non-NULL firstblock values without a prior allocation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
The main thing that xfs_bmap_remap_alloc does is fixing the AGFL, similar to what we do in the space allocator. But the reflink code doesn't touch the allocation btree unlike the normal space allocator, so we couldn't care less about the state of the AGFL. So remove xfs_bmap_remap_alloc and just handle the di_nblocks update in the caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
Add a new helper to be used for reflink extent list additions instead of funneling them through xfs_bmapi_write and overloading the firstblock member in struct xfs_bmalloca and struct xfs_alloc_args. With some small changes to xfs_bmap_remap_alloc this also means we do not need a xfs_bmalloca structure for this case at all. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
For the reflink case we'd much rather pass the required arguments than faking up a struct xfs_bmalloca. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
We never do COW operations for the attr fork, so don't pretend we handle them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Christoph Hellwig authored
bno should be a xfs_fsblock_t, which is 64-bit wides instead of a xfs_aglock_t, which truncates the value to 32 bits. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
- 12 Apr, 2017 3 commits
-
-
Brian Foster authored
Lockdep complains about use of the iolock in inode reclaim context because it doesn't understand that reclaim has the last reference to the inode, and thus an iolock->reclaim->iolock deadlock is not possible. The iolock is technically not necessary in xfs_inactive() and was only added to appease an assert in xfs_free_eofblocks(), which can be called from other non-reclaim contexts. Therefore, just kill the assert and drop the use of the iolock from reclaim context to quiet lockdep. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Eric Sandeen authored
Long ago, all this gunk was added with a lament about problems with gcc's do_div, and a fun recommendation in the changelog: egcs-2.91.66 is the recommended compiler version for building XFS. All this special stuff was needed to work around an old gcc bug, apparently, and it's been there ever since. There should be no need for this anymore, so remove it. Remove the special 32-bit xfs_do_mod as well; just let the kernel's do_div() handle all this. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
Eric Sandeen authored
ndquots is a 32-bit value, and we don't care about the remainder; there is no reason to use do_div here, it seems to be the result of a decade+ historical accident. Worse, the do_div implementation in userspace breaks when fed a 32-bit dividend, so we commented it out there in any case. Change to simple division, and then we can change userspace to match, and mandate a 64-bit dividend in the do_div() in userspace as well. Signed-off-by: Eric Sandeen <sandeen@redhat.com>
-
- 06 Apr, 2017 2 commits
-
-
Darrick J. Wong authored
Apparently FIEMAP for xattrs has been broken since we switched to the iomap backend because of an incorrect check for xattr presence. Also fix the broken locking. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
-
Christoph Hellwig authored
No one cares about the low-level helper anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-
- 03 Apr, 2017 4 commits
-
-
Darrick J. Wong authored
Use the realtime bitmap to return free space information via getfsmap. Eventually this will be superseded by the realtime rmapbt code. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
-
Darrick J. Wong authored
If the reverse-mapping btree isn't available, fall back to the free space btrees to provide partial reverse mapping information. The online scrub tool can make use of even partial information to speed up the data block scan. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
-
Darrick J. Wong authored
Introduce a new ioctl that uses the reverse mapping btree to return information about the physical layout of the filesystem. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
-
Darrick J. Wong authored
Add _query_range and _query_all functions to the realtime bitmap allocator. These two functions are similar in usage to the btree functions with the same name and will be used for getfsmap and scrub. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
-