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| author | Christoph Hellwig <hch@lst.de> | 2017-11-01 18:36:47 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2017-11-03 16:26:26 +0300 |
| commit | a39e596baa07cb1dc19c2ead14c9fd2a30f22352 (patch) | |
| tree | fa9b99af09d60b9c6f85704c6e46bd9f9905c1a2 /fs/xfs/xfs_file.c | |
| parent | 7b565c9f965bac269cc6a1f25c819f77044abf9d (diff) | |
| download | linux-a39e596baa07cb1dc19c2ead14c9fd2a30f22352.tar.xz | |
xfs: support for synchronous DAX faults
Return IOMAP_F_DIRTY from xfs_file_iomap_begin() when asked to prepare
blocks for writing and the inode is pinned, and has dirty fields other
than the timestamps. In __xfs_filemap_fault() we then detect this case
and call dax_finish_sync_fault() to make sure all metadata is committed,
and to insert the 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.
[JK: Added VM_SYNC flag handling]
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'fs/xfs/xfs_file.c')
| -rw-r--r-- | fs/xfs/xfs_file.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 4496b45678de..4827e82d5d2c 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -44,6 +44,7 @@ #include <linux/falloc.h> #include <linux/pagevec.h> #include <linux/backing-dev.h> +#include <linux/mman.h> static const struct vm_operations_struct xfs_file_vm_ops; @@ -1040,7 +1041,11 @@ __xfs_filemap_fault( xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED); if (IS_DAX(inode)) { - ret = dax_iomap_fault(vmf, pe_size, NULL, &xfs_iomap_ops); + pfn_t pfn; + + ret = dax_iomap_fault(vmf, pe_size, &pfn, &xfs_iomap_ops); + if (ret & VM_FAULT_NEEDDSYNC) + ret = dax_finish_sync_fault(vmf, pe_size, pfn); } else { if (write_fault) ret = iomap_page_mkwrite(vmf, &xfs_iomap_ops); @@ -1110,6 +1115,13 @@ xfs_file_mmap( struct file *filp, struct vm_area_struct *vma) { + /* + * We don't support synchronous mappings for non-DAX files. At least + * until someone comes with a sensible use case. + */ + if (!IS_DAX(file_inode(filp)) && (vma->vm_flags & VM_SYNC)) + return -EOPNOTSUPP; + file_accessed(filp); vma->vm_ops = &xfs_file_vm_ops; if (IS_DAX(file_inode(filp))) @@ -1128,6 +1140,7 @@ const struct file_operations xfs_file_operations = { .compat_ioctl = xfs_file_compat_ioctl, #endif .mmap = xfs_file_mmap, + .mmap_supported_flags = MAP_SYNC, .open = xfs_file_open, .release = xfs_file_release, .fsync = xfs_file_fsync, |