summaryrefslogtreecommitdiff
path: root/fs/ext4/file.c
AgeCommit message (Collapse)Author
2019-12-26ext4: Optimize ext4 DIO overwritesJan Kara
Currently we start transaction for mapping every extent for writing using direct IO. This is unnecessary when we know we are overwriting already allocated blocks and the overhead of starting a transaction can be significant especially for multithreaded workloads doing small writes. Use iomap operations that avoid starting a transaction for direct IO overwrites. This improves throughput of 4k random writes - fio jobfile: [global] rw=randrw norandommap=1 invalidate=0 bs=4k numjobs=16 time_based=1 ramp_time=30 runtime=120 group_reporting=1 ioengine=psync direct=1 size=16G filename=file1.0.0:file1.0.1:file1.0.2:file1.0.3:file1.0.4:file1.0.5:file1.0.6:file1.0.7:file1.0.8:file1.0.9:file1.0.10:file1.0.11:file1.0.12:file1.0.13:file1.0.14:file1.0.15:file1.0.16:file1.0.17:file1.0.18:file1.0.19:file1.0.20:file1.0.21:file1.0.22:file1.0.23:file1.0.24:file1.0.25:file1.0.26:file1.0.27:file1.0.28:file1.0.29:file1.0.30:file1.0.31 file_service_type=random nrfiles=32 from 3018MB/s to 4059MB/s in my test VM running test against simulated pmem device (note that before iomap conversion, this workload was able to achieve 3708MB/s because old direct IO path avoided transaction start for overwrites as well). For dax, the win is even larger improving throughput from 3042MB/s to 4311MB/s. Reported-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20191218174433.19380-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-22ext4: Move to shared i_rwsem even without dioread_nolock mount optRitesh Harjani
We were using shared locking only in case of dioread_nolock mount option in case of DIO overwrites. This mount condition is not needed anymore with current code, since:- 1. No race between buffered writes & DIO overwrites. Since buffIO writes takes exclusive lock & DIO overwrites will take shared locking. Also DIO path will make sure to flush and wait for any dirty page cache data. 2. No race between buffered reads & DIO overwrites, since there is no block allocation that is possible with DIO overwrites. So no stale data exposure should happen. Same is the case between DIO reads & DIO overwrites. 3. Also other paths like truncate is protected, since we wait there for any DIO in flight to be over. Reviewed-by: Jan Kara <jack@suse.cz> Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191212055557.11151-4-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-22ext4: Start with shared i_rwsem in case of DIO instead of exclusiveRitesh Harjani
Earlier there was no shared lock in DIO read path. But this patch (16c54688592ce: ext4: Allow parallel DIO reads) simplified some of the locking mechanism while still allowing for parallel DIO reads by adding shared lock in inode DIO read path. But this created problem with mixed read/write workload. It is due to the fact that in DIO path, we first start with exclusive lock and only when we determine that it is a ovewrite IO, we downgrade the lock. This causes the problem, since we still have shared locking in DIO reads. So, this patch tries to fix this issue by starting with shared lock and then switching to exclusive lock only when required based on ext4_dio_write_checks(). Other than that, it also simplifies below cases:- 1. Simplified ext4_unaligned_aio API to ext4_unaligned_io. Previous API was abused in the sense that it was not really checking for AIO anywhere also it used to check for extending writes. So this API was renamed and simplified to ext4_unaligned_io() which actully only checks if the IO is really unaligned. Now, in case of unaligned direct IO, iomap_dio_rw needs to do zeroing of partial block and that will require serialization against other direct IOs in the same block. So we take a exclusive inode lock for any unaligned DIO. In case of AIO we also need to wait for any outstanding IOs to complete so that conversion from unwritten to written is completed before anyone try to map the overlapping block. Hence we take exclusive inode lock and also wait for inode_dio_wait() for unaligned DIO case. Please note since we are anyway taking an exclusive lock in unaligned IO, inode_dio_wait() becomes a no-op in case of non-AIO DIO. 2. Added ext4_extending_io(). This checks if the IO is extending the file. 3. Added ext4_dio_write_checks(). In this we start with shared inode lock and only switch to exclusive lock if required. So in most cases with aligned, non-extending, dioread_nolock & overwrites, it tries to write with a shared lock. If not, then we restart the operation in ext4_dio_write_checks(), after acquiring exclusive lock. Reviewed-by: Jan Kara <jack@suse.cz> Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191212055557.11151-3-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-22ext4: fix ext4_dax_read/write inode locking sequence for IOCB_NOWAITRitesh Harjani
Apparently our current rwsem code doesn't like doing the trylock, then lock for real scheme. So change our dax read/write methods to just do the trylock for the RWF_NOWAIT case. This seems to fix AIM7 regression in some scalable filesystems upto ~25% in some cases. Claimed in commit 942491c9e6d6 ("xfs: fix AIM7 regression") Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191212055557.11151-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05ext4: introduce direct I/O write using iomap infrastructureMatthew Bobrowski
This patch introduces a new direct I/O write path which makes use of the iomap infrastructure. All direct I/O writes are now passed from the ->write_iter() callback through to the new direct I/O handler ext4_dio_write_iter(). This function is responsible for calling into the iomap infrastructure via iomap_dio_rw(). Code snippets from the existing direct I/O write code within ext4_file_write_iter() such as, checking whether the I/O request is unaligned asynchronous I/O, or whether the write will result in an overwrite have effectively been moved out and into the new direct I/O ->write_iter() handler. The block mapping flags that are eventually passed down to ext4_map_blocks() from the *_get_block_*() suite of routines have been taken out and introduced within ext4_iomap_alloc(). For inode extension cases, ext4_handle_inode_extension() is effectively the function responsible for performing such metadata updates. This is called after iomap_dio_rw() has returned so that we can safely determine whether we need to potentially truncate any allocated blocks that may have been prepared for this direct I/O write. We don't perform the inode extension, or truncate operations from the ->end_io() handler as we don't have the original I/O 'length' available there. The ->end_io() however is responsible fo converting allocated unwritten extents to written extents. In the instance of a short write, we fallback and complete the remainder of the I/O using buffered I/O via ext4_buffered_write_iter(). The existing buffer_head direct I/O implementation has been removed as it's now redundant. [ Fix up ext4_dio_write_iter() per Jan's comments at https://lore.kernel.org/r/20191105135932.GN22379@quack2.suse.cz -- TYT ] Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/e55db6f12ae6ff017f36774135e79f3e7b0333da.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05ext4: move inode extension check out from ext4_iomap_alloc()Matthew Bobrowski
Lift the inode extension/orphan list handling code out from ext4_iomap_alloc() and apply it within the ext4_dax_write_iter(). Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/fd5c84db25d5d0da87d97ed4c36fd844f57da759.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05ext4: move inode extension/truncate code out from ->iomap_end() callbackMatthew Bobrowski
In preparation for implementing the iomap direct I/O modifications, the inode extension/truncate code needs to be moved out from the ext4_iomap_end() callback. For direct I/O, if the current code remained, it would behave incorrrectly. Updating the inode size prior to converting unwritten extents would potentially allow a racing direct I/O read to find unwritten extents before being converted correctly. The inode extension/truncate code now resides within a new helper ext4_handle_inode_extension(). This function has been designed so that it can accommodate for both DAX and direct I/O extension/truncate operations. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/d41ffa26e20b15b12895812c3cad7c91a6a59bc6.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05ext4: introduce direct I/O read using iomap infrastructureMatthew Bobrowski
This patch introduces a new direct I/O read path which makes use of the iomap infrastructure. The new function ext4_do_read_iter() is responsible for calling into the iomap infrastructure via iomap_dio_rw(). If the read operation performed on the inode is not supported, which is checked via ext4_dio_supported(), then we simply fallback and complete the I/O using buffered I/O. Existing direct I/O read code path has been removed, as it is now redundant. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/f98a6f73fadddbfbad0fc5ed04f712ca0b799f37.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05ext4: introduce new callback for IOMAP_REPORTMatthew Bobrowski
As part of the ext4_iomap_begin() cleanups that precede this patch, we also split up the IOMAP_REPORT branch into a completely separate ->iomap_begin() callback named ext4_iomap_begin_report(). Again, the raionale for this change is to reduce the overall clutter within ext4_iomap_begin(). Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/5c97a569e26ddb6696e3d3ac9fbde41317e029a0.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-09-21Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Added new ext4 debugging ioctls to allow userspace to get information about the state of the extent status cache. Dropped workaround for pre-1970 dates which were encoded incorrectly in pre-4.4 kernels. Since both the kernel correctly generates, and e2fsck detects and fixes this issue for the past four years, it'e time to drop the workaround. (Also, it's not like files with dates in the distant past were all that common in the first place.) A lot of miscellaneous bug fixes and cleanups, including some ext4 Documentation fixes. Also included are two minor bug fixes in fs/unicode" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits) unicode: make array 'token' static const, makes object smaller unicode: Move static keyword to the front of declarations ext4: add missing bigalloc documentation. ext4: fix kernel oops caused by spurious casefold flag ext4: fix integer overflow when calculating commit interval ext4: use percpu_counters for extent_status cache hits/misses ext4: fix potential use after free after remounting with noblock_validity jbd2: add missing tracepoint for reserved handle ext4: fix punch hole for inline_data file systems ext4: rework reserved cluster accounting when invalidating pages ext4: documentation fixes ext4: treat buffers with write errors as containing valid data ext4: fix warning inside ext4_convert_unwritten_extents_endio ext4: set error return correctly when ext4_htree_store_dirent fails ext4: drop legacy pre-1970 encoding workaround ext4: add new ioctl EXT4_IOC_GET_ES_CACHE ext4: add a new ioctl EXT4_IOC_GETSTATE ext4: add a new ioctl EXT4_IOC_CLEAR_ES_CACHE jbd2: flush_descriptor(): Do not decrease buffer head's ref count ext4: remove unnecessary error check ...
2019-08-12ext4: add basic fs-verity supportEric Biggers
Add most of fs-verity support to ext4. fs-verity is a filesystem feature that enables transparent integrity protection and authentication of read-only files. It uses a dm-verity like mechanism at the file level: a Merkle tree is used to verify any block in the file in log(filesize) time. It is implemented mainly by helper functions in fs/verity/. See Documentation/filesystems/fsverity.rst for the full documentation. This commit adds all of ext4 fs-verity support except for the actual data verification, including: - Adding a filesystem feature flag and an inode flag for fs-verity. - Implementing the fsverity_operations to support enabling verity on an inode and reading/writing the verity metadata. - Updating ->write_begin(), ->write_end(), and ->writepages() to support writing verity metadata pages. - Calling the fs-verity hooks for ->open(), ->setattr(), and ->ioctl(). ext4 stores the verity metadata (Merkle tree and fsverity_descriptor) past the end of the file, starting at the first 64K boundary beyond i_size. This approach works because (a) verity files are readonly, and (b) pages fully beyond i_size aren't visible to userspace but can be read/written internally by ext4 with only some relatively small changes to ext4. This approach avoids having to depend on the EA_INODE feature and on rearchitecturing ext4's xattr support to support paging multi-gigabyte xattrs into memory, and to support encrypting xattrs. Note that the verity metadata *must* be encrypted when the file is, since it contains hashes of the plaintext data. This patch incorporates work by Theodore Ts'o and Chandan Rajendra. Reviewed-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-08-11ext4: remove unnecessary error checkShi Siyuan
Remove unnecessary error check in ext4_file_write_iter(), because this check will be done in upcoming later function -- ext4_write_checks() -> generic_write_checks() Change-Id: I7b0ab27f693a50765c15b5eaa3f4e7c38f42e01e Signed-off-by: shisiyuan <shisiyuan@xiaomi.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-07-18Merge tag 'libnvdimm-for-5.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "Primarily just the virtio_pmem driver: - virtio_pmem The new virtio_pmem facility introduces a paravirtualized persistent memory device that allows a guest VM to use DAX mechanisms to access a host-file with host-page-cache. It arranges for MAP_SYNC to be disabled and instead triggers a host fsync() when a 'write-cache flush' command is sent to the virtual disk device. - Miscellaneous small fixups" * tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: virtio_pmem: fix sparse warning xfs: disable map_sync for async flush ext4: disable map_sync for async flush dax: check synchronous mapping is supported dm: enable synchronous dax libnvdimm: add dax_dev sync flag virtio-pmem: Add virtio pmem driver libnvdimm: nd_region flush callback support libnvdimm, namespace: Drop uuid_t implementation detail
2019-07-05ext4: disable map_sync for async flushPankaj Gupta
Dont support 'MAP_SYNC' with non-DAX files and DAX files with asynchronous dax_device. Virtio pmem provides asynchronous host page cache flush mechanism. We don't support 'MAP_SYNC' with virtio pmem and ext4. Signed-off-by: Pankaj Gupta <pagupta@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-06-09ext4: enforce the immutable flag on open filesTheodore Ts'o
According to the chattr man page, "a file with the 'i' attribute cannot be modified..." Historically, this was only enforced when the file was opened, per the rest of the description, "... and the file can not be opened in write mode". There is general agreement that we should standardize all file systems to prevent modifications even for files that were opened at the time the immutable flag is set. Eventually, a change to enforce this at the VFS layer should be landing in mainline. Until then, enforce this at the ext4 level to prevent xfstests generic/553 from failing. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: stable@kernel.org
2019-05-10ext4: fix data corruption caused by overlapping unaligned and aligned IOLukas Czerner
Unaligned AIO must be serialized because the zeroing of partial blocks of unaligned AIO can result in data corruption in case it's overlapping another in flight IO. Currently we wait for all unwritten extents before we submit unaligned AIO which protects data in case of unaligned AIO is following overlapping IO. However if a unaligned AIO is followed by overlapping aligned AIO we can still end up corrupting data. To fix this, we must make sure that the unaligned AIO is the only IO in flight by waiting for unwritten extents conversion not just before the IO submission, but right after it as well. This problem can be reproduced by xfstest generic/538 Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2019-03-14ext4: fix data corruption caused by unaligned direct AIOLukas Czerner
Ext4 needs to serialize unaligned direct AIO because the zeroing of partial blocks of two competing unaligned AIOs can result in data corruption. However it decides not to serialize if the potentially unaligned aio is past i_size with the rationale that no pending writes are possible past i_size. Unfortunately if the i_size is not block aligned and the second unaligned write lands past i_size, but still into the same block, it has the potential of corrupting the previous unaligned write to the same block. This is (very simplified) reproducer from Frank // 41472 = (10 * 4096) + 512 // 37376 = 41472 - 4096 ftruncate(fd, 41472); io_prep_pwrite(iocbs[0], fd, buf[0], 4096, 37376); io_prep_pwrite(iocbs[1], fd, buf[1], 4096, 41472); io_submit(io_ctx, 1, &iocbs[1]); io_submit(io_ctx, 1, &iocbs[2]); io_getevents(io_ctx, 2, 2, events, NULL); Without this patch the 512B range from 40960 up to the start of the second unaligned write (41472) is going to be zeroed overwriting the data written by the first write. This is a data corruption. 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 00009200 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 * 0000a000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0000a200 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 With this patch the data corruption is avoided because we will recognize the unaligned_aio and wait for the unwritten extent conversion. 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 00009200 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 * 0000a200 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31 * 0000b200 Reported-by: Frank Sorenson <fsorenso@redhat.com> Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Fixes: e9e3bcecf44c ("ext4: serialize unaligned asynchronous DIO") Cc: stable@vger.kernel.org
2018-08-17dax: remove VM_MIXEDMAP for fsdax and device daxDave Jiang
This patch is reworked from an earlier patch that Dan has posted: https://patchwork.kernel.org/patch/10131727/ VM_MIXEDMAP is used by dax to direct mm paths like vm_normal_page() that the memory page it is dealing with is not typical memory from the linear map. The get_user_pages_fast() path, since it does not resolve the vma, is already using {pte,pmd}_devmap() as a stand-in for VM_MIXEDMAP, so we use that as a VM_MIXEDMAP replacement in some locations. In the cases where there is no pte to consult we fallback to using vma_is_dax() to detect the VM_MIXEDMAP special case. Now that we have explicit driver pfn_t-flag opt-in/opt-out for get_user_pages() support for DAX we can stop setting VM_MIXEDMAP. This also means we no longer need to worry about safely manipulating vm_flags in a future where we support dynamically changing the dax mode of a file. DAX should also now be supported with madvise_behavior(), vma_merge(), and copy_page_range(). This patch has been tested against ndctl unit test. It has also been tested against xfstests commit: 625515d using fake pmem created by memmap and no additional issues have been observed. Link: http://lkml.kernel.org/r/152847720311.55924.16999195879201817653.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-13ext4: do not update s_last_mounted of a frozen fsAmir Goldstein
If fs is frozen after mount and before the first file open, the update of s_last_mounted bypasses freeze protection and prints out a WARNING splat: $ mount /vdf $ fsfreeze -f /vdf $ cat /vdf/foo [ 31.578555] WARNING: CPU: 1 PID: 1415 at fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82 [ 31.614016] Call Trace: [ 31.614997] __ext4_journal_start_sb+0xe4/0x1a4 [ 31.616771] ? ext4_file_open+0xb6/0x189 [ 31.618094] ext4_file_open+0xb6/0x189 If fs is frozen, skip s_last_mounted update. [backport hint: to apply to stable tree, need to apply also patches vfs: add the sb_start_intwrite_trylock() helper ext4: factor out helper ext4_sample_last_mounted()] Cc: stable@vger.kernel.org Fixes: bc0b0d6d69ee ("ext4: update the s_last_mounted field in the superblock") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-13ext4: factor out helper ext4_sample_last_mounted()Amir Goldstein
Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-13fs: ext4: add new return type vm_fault_tSouptick Joarder
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. commit 1c8f422059ae ("mm: change return type to vm_fault_t") Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-01-07ext4: fix ENOSPC handling in DAX page fault handlerJan Kara
When allocation of underlying block for a page fault fails, we fail the fault with SIGBUS. However we may well hit ENOSPC just due to lots of free blocks being held by the running / committing transaction. So propagate the error from ext4_iomap_begin() and implement do standard allocation retry loop in ext4_dax_huge_fault(). Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-01-07dax: pass detailed error code from dax_iomap_fault()Jan Kara
Ext4 needs to pass through error from its iomap handler to the page fault handler so that it can properly detect ENOSPC and force transaction commit and retry the fault (and block allocation). Add argument to dax_iomap_fault() for passing such error. Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-11-17Merge tag 'libnvdimm-for-4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm and dax updates from Dan Williams: "Save for a few late fixes, all of these commits have shipped in -next releases since before the merge window opened, and 0day has given a build success notification. The ext4 touches came from Jan, and the xfs touches have Darrick's reviewed-by. An xfstest for the MAP_SYNC feature has been through a few round of reviews and is on track to be merged. - Introduce MAP_SYNC and MAP_SHARED_VALIDATE, a mechanism to enable 'userspace flush' of persistent memory updates via filesystem-dax mappings. It arranges for any filesystem metadata updates that may be required to satisfy a write fault to also be flushed ("on disk") before the kernel returns to userspace from the fault handler. Effectively every write-fault that dirties metadata completes an fsync() before returning from the fault handler. The new MAP_SHARED_VALIDATE mapping type guarantees that the MAP_SYNC flag is validated as supported by the filesystem's ->mmap() file operation. - Add support for the standard ACPI 6.2 label access methods that replace the NVDIMM_FAMILY_INTEL (vendor specific) label methods. This enables interoperability with environments that only implement the standardized methods. - Add support for the ACPI 6.2 NVDIMM media error injection methods. - Add support for the NVDIMM_FAMILY_INTEL v1.6 DIMM commands for latch last shutdown status, firmware update, SMART error injection, and SMART alarm threshold control. - Cleanup physical address information disclosures to be root-only. - Fix revalidation of the DIMM "locked label area" status to support dynamic unlock of the label area. - Expand unit test infrastructure to mock the ACPI 6.2 Translate SPA (system-physical-address) command and error injection commands. Acknowledgements that came after the commits were pushed to -next: - 957ac8c421ad ("dax: fix PMD faults on zero-length files"): Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> - a39e596baa07 ("xfs: support for synchronous DAX faults") and 7b565c9f965b ("xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()") Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>" * tag 'libnvdimm-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (49 commits) acpi, nfit: add 'Enable Latch System Shutdown Status' command support dax: fix general protection fault in dax_alloc_inode dax: fix PMD faults on zero-length files dax: stop requiring a live device for dax_flush() brd: remove dax support dax: quiet bdev_dax_supported() fs, dax: unify IOMAP_F_DIRTY read vs write handling policy in the dax core tools/testing/nvdimm: unit test clear-error commands acpi, nfit: validate commands against the device type tools/testing/nvdimm: stricter bounds checking for error injection commands xfs: support for synchronous DAX faults xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault() ext4: Support for synchronous DAX faults ext4: Simplify error handling in ext4_dax_huge_fault() dax: Implement dax_finish_sync_fault() dax, iomap: Add support for synchronous faults mm: Define MAP_SYNC and VM_SYNC flags dax: Allow tuning whether dax_insert_mapping_entry() dirties entry dax: Allow dax_iomap_fault() to return pfn dax: Fix comment describing dax_iomap_fault() ...
2017-11-14Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: - Add support for online resizing of file systems with bigalloc - Fix a two data corruption bugs involving DAX, as well as a corruption bug after a crash during a racing fallocate and delayed allocation. - Finally, a number of cleanups and optimizations. * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: improve smp scalability for inode generation ext4: add support for online resizing with bigalloc ext4: mention noload when recovering on read-only device Documentation: fix little inconsistencies ext4: convert timers to use timer_setup() jbd2: convert timers to use timer_setup() ext4: remove duplicate extended attributes defs ext4: add ext4_should_use_dax() ext4: add sanity check for encryption + DAX ext4: prevent data corruption with journaling + DAX ext4: prevent data corruption with inline data + DAX ext4: fix interaction between i_size, fallocate, and delalloc after a crash ext4: retry allocations conservatively ext4: Switch to iomap for SEEK_HOLE / SEEK_DATA ext4: Add iomap support for inline data iomap: Add IOMAP_F_DATA_INLINE flag iomap: Switch from blkno to disk offset
2017-11-14Merge tag 'fscrypt-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Lots of cleanups, mostly courtesy by Eric Biggers" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: lock mutex before checking for bounce page pool fscrypt: add a documentation file for filesystem-level encryption ext4: switch to fscrypt_prepare_setattr() ext4: switch to fscrypt_prepare_lookup() ext4: switch to fscrypt_prepare_rename() ext4: switch to fscrypt_prepare_link() ext4: switch to fscrypt_file_open() fscrypt: new helper function - fscrypt_prepare_setattr() fscrypt: new helper function - fscrypt_prepare_lookup() fscrypt: new helper function - fscrypt_prepare_rename() fscrypt: new helper function - fscrypt_prepare_link() fscrypt: new helper function - fscrypt_file_open() fscrypt: new helper function - fscrypt_require_key() fscrypt: remove unneeded empty fscrypt_operations structs fscrypt: remove ->is_encrypted() fscrypt: switch from ->is_encrypted() to IS_ENCRYPTED() fs, fscrypt: add an S_ENCRYPTED inode flag fscrypt: clean up include file mess
2017-11-03ext4: Support for synchronous DAX faultsJan Kara
We return IOMAP_F_DIRTY flag from ext4_iomap_begin() when asked to prepare blocks for writing and the inode has some uncommitted metadata changes. In the fault handler ext4_dax_fault() we then detect this case (through VM_FAULT_NEEDDSYNC return value) and call helper dax_finish_sync_fault() to flush metadata changes and insert page table entry. Note that this will also dirty corresponding radix tree entry which is what we want - fsync(2) will still provide data integrity guarantees for applications not using userspace flushing. And applications using userspace flushing can avoid calling fsync(2) and thus avoid the performance overhead. Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-03ext4: Simplify error handling in ext4_dax_huge_fault()Jan Kara
If transaction starting fails, just bail out of the function immediately instead of checking for that condition throughout the function. Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-03dax: Allow dax_iomap_fault() to return pfnJan Kara
For synchronous page fault dax_iomap_fault() will need to return PFN which will then need to be inserted into page tables after fsync() completes. Add necessary parameter to dax_iomap_fault(). Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-18ext4: switch to fscrypt_file_open()Eric Biggers
Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-10-01ext4: Switch to iomap for SEEK_HOLE / SEEK_DATAChristoph Hellwig
Switch to the iomap_seek_hole and iomap_seek_data helpers for implementing lseek SEEK_HOLE / SEEK_DATA, and remove all the code that isn't needed any more. Note that with this patch ext4 will now always depend on the iomap code instead of only when CONFIG_DAX is enabled, and it requires adding a call into the extent status tree for iomap_begin as well to properly deal with delalloc extents. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> [More fixes and cleanups by Andreas]
2017-09-14Merge branch 'work.read_write' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull nowait read support from Al Viro: "Support IOCB_NOWAIT for buffered reads and block devices" * 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: block_dev: support RFW_NOWAIT on block device nodes fs: support RWF_NOWAIT for buffered reads fs: support IOCB_NOWAIT in generic_file_buffered_read fs: pass iocb to do_generic_file_read
2017-09-14Merge branch 'work.mount' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull mount flag updates from Al Viro: "Another chunk of fmount preparations from dhowells; only trivial conflicts for that part. It separates MS_... bits (very grotty mount(2) ABI) from the struct super_block ->s_flags (kernel-internal, only a small subset of MS_... stuff). This does *not* convert the filesystems to new constants; only the infrastructure is done here. The next step in that series is where the conflicts would be; that's the conversion of filesystems. It's purely mechanical and it's better done after the merge, so if you could run something like list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$') sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \ -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \ -e 's/\<MS_NODEV\>/SB_NODEV/g' \ -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \ -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \ -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \ -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \ -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \ -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \ -e 's/\<MS_SILENT\>/SB_SILENT/g' \ -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \ -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \ -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \ -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \ $list and commit it with something along the lines of 'convert filesystems away from use of MS_... constants' as commit message, it would save a quite a bit of headache next cycle" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: VFS: Differentiate mount flags (MS_*) from internal superblock flags VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
2017-09-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - various misc bits - DAX updates - OCFS2 - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits) mm,fork: introduce MADV_WIPEONFORK x86,mpx: make mpx depend on x86-64 to free up VMA flag mm: add /proc/pid/smaps_rollup mm: hugetlb: clear target sub-page last when clearing huge page mm: oom: let oom_reap_task and exit_mmap run concurrently swap: choose swap device according to numa node mm: replace TIF_MEMDIE checks by tsk_is_oom_victim mm, oom: do not rely on TIF_MEMDIE for memory reserves access z3fold: use per-cpu unbuddied lists mm, swap: don't use VMA based swap readahead if HDD is used as swap mm, swap: add sysfs interface for VMA based swap readahead mm, swap: VMA based swap readahead mm, swap: fix swap readahead marking mm, swap: add swap readahead hit statistics mm/vmalloc.c: don't reinvent the wheel but use existing llist API mm/vmstat.c: fix wrong comment selftests/memfd: add memfd_create hugetlbfs selftest mm/shmem: add hugetlbfs support to memfd_create() mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas() ...
2017-09-06mm: remove nr_pages argument from pagevec_lookup{,_range}()Jan Kara
All users of pagevec_lookup() and pagevec_lookup_range() now pass PAGEVEC_SIZE as a desired number of pages. Just drop the argument. Link: http://lkml.kernel.org/r/20170726114704.7626-11-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06ext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff()Jan Kara
Use pagevec_lookup_range() in ext4_find_unwritten_pgoff() since we are interested only in pages in the given range. Simplify the logic as a result of not getting pages out of range and index getting automatically advanced. Link: http://lkml.kernel.org/r/20170726114704.7626-6-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06mm: make pagevec_lookup() update indexJan Kara
Make pagevec_lookup() (and underlying find_get_pages()) update index to the next page where iteration should continue. Most callers want this and also pagevec_lookup_tag() already does this. Link: http://lkml.kernel.org/r/20170726114704.7626-3-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06dax: use common 4k zero page for dax mmap readsRoss Zwisler
When servicing mmap() reads from file holes the current DAX code allocates a page cache page of all zeroes and places the struct page pointer in the mapping->page_tree radix tree. This has three major drawbacks: 1) It consumes memory unnecessarily. For every 4k page that is read via a DAX mmap() over a hole, we allocate a new page cache page. This means that if you read 1GiB worth of pages, you end up using 1GiB of zeroed memory. This is easily visible by looking at the overall memory consumption of the system or by looking at /proc/[pid]/smaps: 7f62e72b3000-7f63272b3000 rw-s 00000000 103:00 12 /root/dax/data Size: 1048576 kB Rss: 1048576 kB Pss: 1048576 kB Shared_Clean: 0 kB Shared_Dirty: 0 kB Private_Clean: 1048576 kB Private_Dirty: 0 kB Referenced: 1048576 kB Anonymous: 0 kB LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 0 kB SwapPss: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Locked: 0 kB 2) It is slower than using a common zero page because each page fault has more work to do. Instead of just inserting a common zero page we have to allocate a page cache page, zero it, and then insert it. Here are the average latencies of dax_load_hole() as measured by ftrace on a random test box: Old method, using zeroed page cache pages: 3.4 us New method, using the common 4k zero page: 0.8 us This was the average latency over 1 GiB of sequential reads done by this simple fio script: [global] size=1G filename=/root/dax/data fallocate=none [io] rw=read ioengine=mmap 3) The fact that we had to check for both DAX exceptional entries and for page cache pages in the radix tree made the DAX code more complex. Solve these issues by following the lead of the DAX PMD code and using a common 4k zero page instead. As with the PMD code we will now insert a DAX exceptional entry into the radix tree instead of a struct page pointer which allows us to remove all the special casing in the DAX code. Note that we do still pretty aggressively check for regular pages in the DAX radix tree, especially where we take action based on the bits set in the page. If we ever find a regular page in our radix tree now that most likely means that someone besides DAX is inserting pages (which has happened lots of times in the past), and we want to find that out early and fail loudly. This solution also removes the extra memory consumption. Here is that same /proc/[pid]/smaps after 1GiB of reading from a hole with the new code: 7f2054a74000-7f2094a74000 rw-s 00000000 103:00 12 /root/dax/data Size: 1048576 kB Rss: 0 kB Pss: 0 kB Shared_Clean: 0 kB Shared_Dirty: 0 kB Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 0 kB Anonymous: 0 kB LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 0 kB SwapPss: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Locked: 0 kB Overall system memory consumption is similarly improved. Another major change is that we remove dax_pfn_mkwrite() from our fault flow, and instead rely on the page fault itself to make the PTE dirty and writeable. The following description from the patch adding the vm_insert_mixed_mkwrite() call explains this a little more: "To be able to use the common 4k zero page in DAX we need to have our PTE fault path look more like our PMD fault path where a PTE entry can be marked as dirty and writeable as it is first inserted rather than waiting for a follow-up dax_pfn_mkwrite() => finish_mkwrite_fault() call. Right now we can rely on having a dax_pfn_mkwrite() call because we can distinguish between these two cases in do_wp_page(): case 1: 4k zero page => writable DAX storage case 2: read-only DAX storage => writeable DAX storage This distinction is made by via vm_normal_page(). vm_normal_page() returns false for the common 4k zero page, though, just as it does for DAX ptes. Instead of special casing the DAX + 4k zero page case we will simplify our DAX PTE page fault sequence so that it matches our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper. We will instead use dax_iomap_fault() to handle write-protection faults. This means that insert_pfn() needs to follow the lead of insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If 'mkwrite' is set insert_pfn() will do the work that was previously done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path" Link: http://lkml.kernel.org/r/20170724170616.25810-4-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-04fs: support RWF_NOWAIT for buffered readsChristoph Hellwig
This is based on the old idea and code from Milosz Tanski. With the aio nowait code it becomes mostly trivial now. Buffered writes continue to return -EOPNOTSUPP if RWF_NOWAIT is passed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-08-24ext4: fix fault handling when mounted with -o dax,roRandy Dodgen
If an ext4 filesystem is mounted with both the DAX and read-only options, executables on that filesystem will fail to start (claiming 'Segmentation fault') due to the fault handler returning VM_FAULT_SIGBUS. This is due to the DAX fault handler (see ext4_dax_huge_fault) attempting to write to the journal when FAULT_FLAG_WRITE is set. This is the wrong behavior for write faults which will lead to a COW page; in particular, this fails for readonly mounts. This change avoids journal writes for faults that are expected to COW. It might be the case that this could be better handled in ext4_iomap_begin / ext4_iomap_end (called via iomap_ops inside dax_iomap_fault). These is some overlap already (e.g. grabbing journal handles). Signed-off-by: Randy Dodgen <dodgen@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2017-08-24ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsetsDarrick J. Wong
In the ext4 implementations of SEEK_HOLE and SEEK_DATA, make sure we return -ENXIO for negative offsets instead of banging around inside the extent code and returning -EFSCORRUPTED. Reported-by: Mateusz S <muttdini@gmail.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org # 4.6
2017-08-05ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesizeJan Kara
ext4_find_unwritten_pgoff() does not properly handle a situation when starting index is in the middle of a page and blocksize < pagesize. The following command shows the bug on filesystem with 1k blocksize: xfs_io -f -c "falloc 0 4k" \ -c "pwrite 1k 1k" \ -c "pwrite 3k 1k" \ -c "seek -a -r 0" foo In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048, SEEK_DATA) will return the correct result. Fix the problem by neglecting buffers in a page before starting offset. Reported-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jan Kara <jack@suse.cz> CC: stable@vger.kernel.org # 3.8+
2017-07-17VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)David Howells
Firstly by applying the following with coccinelle's spatch: @@ expression SB; @@ -SB->s_flags & MS_RDONLY +sb_rdonly(SB) to effect the conversion to sb_rdonly(sb), then by applying: @@ expression A, SB; @@ ( -(!sb_rdonly(SB)) && A +!sb_rdonly(SB) && A | -A != (sb_rdonly(SB)) +A != sb_rdonly(SB) | -A == (sb_rdonly(SB)) +A == sb_rdonly(SB) | -!(sb_rdonly(SB)) +!sb_rdonly(SB) | -A && (sb_rdonly(SB)) +A && sb_rdonly(SB) | -A || (sb_rdonly(SB)) +A || sb_rdonly(SB) | -(sb_rdonly(SB)) != A +sb_rdonly(SB) != A | -(sb_rdonly(SB)) == A +sb_rdonly(SB) == A | -(sb_rdonly(SB)) && A +sb_rdonly(SB) && A | -(sb_rdonly(SB)) || A +sb_rdonly(SB) || A ) @@ expression A, B, SB; @@ ( -(sb_rdonly(SB)) ? 1 : 0 +sb_rdonly(SB) | -(sb_rdonly(SB)) ? A : B +sb_rdonly(SB) ? A : B ) to remove left over excess bracketage and finally by applying: @@ expression A, SB; @@ ( -(A & MS_RDONLY) != sb_rdonly(SB) +(bool)(A & MS_RDONLY) != sb_rdonly(SB) | -(A & MS_RDONLY) == sb_rdonly(SB) +(bool)(A & MS_RDONLY) == sb_rdonly(SB) ) to make comparisons against the result of sb_rdonly() (which is a bool) work correctly. Signed-off-by: David Howells <dhowells@redhat.com>
2017-07-09Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The first major feature for ext4 this merge window is the largedir feature, which allows ext4 directories to support over 2 billion directory entries (assuming ~64 byte file names; in practice, users will run into practical performance limits first.) This feature was originally written by the Lustre team, and credit goes to Artem Blagodarenko from Seagate for getting this feature upstream. The second major major feature allows ext4 to support extended attribute values up to 64k. This feature was also originally from Lustre, and has been enhanced by Tahsin Erdogan from Google with a deduplication feature so that if multiple files have the same xattr value (for example, Windows ACL's stored by Samba), only one copy will be stored on disk for encoding and caching efficiency. We also have the usual set of bug fixes, cleanups, and optimizations" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits) ext4: fix spelling mistake: "prellocated" -> "preallocated" ext4: fix __ext4_new_inode() journal credits calculation ext4: skip ext4_init_security() and encryption on ea_inodes fs: generic_block_bmap(): initialize all of the fields in the temp bh ext4: change fast symlink test to not rely on i_blocks ext4: require key for truncate(2) of encrypted file ext4: don't bother checking for encryption key in ->mmap() ext4: check return value of kstrtoull correctly in reserved_clusters_store ext4: fix off-by-one fsmap error on 1k block filesystems ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry() ext4: return EIO on read error in ext4_find_entry ext4: forbid encrypting root directory ext4: send parallel discards on commit completions ext4: avoid unnecessary stalls in ext4_evict_inode() ext4: add nombcache mount option ext4: strong binding of xattr inode references ext4: eliminate xattr entry e_hash recalculation for removes ext4: reserve space for xattr entries/names quota: add get_inode_usage callback to transfer multi-inode charges ext4: xattr inode deduplication ...
2017-06-23ext4: don't bother checking for encryption key in ->mmap()Eric Biggers
Since only an open file can be mmap'ed, and we only allow open()ing an encrypted file when its key is available, there is no need to check for the key again before permitting each mmap(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-20ext4: nowait aio supportGoldwyn Rodrigues
Return EAGAIN if any of the following checks fail for direct I/O: + i_rwsem is lockable + Writing beyond end of file (will trigger allocation) + Blocks are not allocated at the write location Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-05-24ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()Eryu Guan
ext4_find_unwritten_pgoff() is used to search for offset of hole or data in page range [index, end] (both inclusive), and the max number of pages to search should be at least one, if end == index. Otherwise the only page is missed and no hole or data is found, which is not correct. When block size is smaller than page size, this can be demonstrated by preallocating a file with size smaller than page size and writing data to the last block. E.g. run this xfs_io command on a 1k block size ext4 on x86_64 host. # xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \ -c "seek -d 0" /mnt/ext4/testfile wrote 1024/1024 bytes at offset 2048 1 KiB, 1 ops; 0.0000 sec (42.459 MiB/sec and 43478.2609 ops/sec) Whence Result DATA EOF Data at offset 2k was missed, and lseek(2) returned ENXIO. This is unconvered by generic/285 subtest 07 and 08 on ppc64 host, where pagesize is 64k. Because a recent change to generic/285 reduced the preallocated file size to smaller than 64k. Signed-off-by: Eryu Guan <eguan@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-21ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()Jan Kara
There is an off-by-one error in loop termination conditions in ext4_find_unwritten_pgoff() since 'end' may index a page beyond end of desired range if 'endoff' is page aligned. It doesn't have any visible effects but still it is good to fix it. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21ext4: fix SEEK_HOLEJan Kara
Currently, SEEK_HOLE implementation in ext4 may both return that there's a hole at some offset although that offset already has data and skip some holes during a search for the next hole. The first problem is demostrated by: xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "seek -h 0" file wrote 57344/57344 bytes at offset 0 56 KiB, 14 ops; 0.0000 sec (2.054 GiB/sec and 538461.5385 ops/sec) Whence Result HOLE 0 Where we can see that SEEK_HOLE wrongly returned offset 0 as containing a hole although we have written data there. The second problem can be demonstrated by: xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k" -c "seek -h 0" file wrote 57344/57344 bytes at offset 0 56 KiB, 14 ops; 0.0000 sec (1.978 GiB/sec and 518518.5185 ops/sec) wrote 8192/8192 bytes at offset 131072 8 KiB, 2 ops; 0.0000 sec (2 GiB/sec and 500000.0000 ops/sec) Whence Result HOLE 139264 Where we can see that hole at offsets 56k..128k has been ignored by the SEEK_HOLE call. The underlying problem is in the ext4_find_unwritten_pgoff() which is just buggy. In some cases it fails to update returned offset when it finds a hole (when no pages are found or when the first found page has higher index than expected), in some cases conditions for detecting hole are just missing (we fail to detect a situation where indices of returned pages are not contiguous). Fix ext4_find_unwritten_pgoff() to properly detect non-contiguous page indices and also handle all cases where we got less pages then expected in one place and handle it properly there. CC: stable@vger.kernel.org Fixes: c8c0df241cc2719b1262e627f999638411934f60 CC: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
generated by cgit (git 2.34.1) at 2024-06-07 04:00:11 +0000