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xfs: remove xfs_filemap_map_pages() wrapper

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Patch series "Prevent ->map_pages from sleeping", v2.

In preparation for a larger patch series which will handle (some, easy)
page faults protected only by RCU, change the two filesystems which have
sleeping locks to not take them and hold the RCU lock around calls to
->map_page to prevent other filesystems from adding sleeping locks.


This patch (of 3):

XFS doesn't actually need to be holding the XFS_MMAPLOCK_SHARED to do
this.  filemap_map_pages() cannot bring new folios into the page cache
and the folio lock is taken during filemap_map_pages() which provides
sufficient protection against a truncation or hole punch.

Link: https://lkml.kernel.org/r/20230327174515.1811532-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20230327174515.1811532-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-03-27 18:45:13 +01:00 committed by Andrew Morton
parent 02cd4eb81c
commit 945ea457b5
1 changed files with 1 additions and 16 deletions
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17
fs/xfs/xfs_file.c
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@ -1388,25 +1388,10 @@ xfs_filemap_pfn_mkwrite(
return __xfs_filemap_fault(vmf, PE_SIZE_PTE, true);
}
static vm_fault_t
xfs_filemap_map_pages(
struct vm_fault *vmf,
pgoff_t start_pgoff,
pgoff_t end_pgoff)
{
struct inode *inode = file_inode(vmf->vma->vm_file);
vm_fault_t ret;
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
ret = filemap_map_pages(vmf, start_pgoff, end_pgoff);
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
return ret;
}
static const struct vm_operations_struct xfs_file_vm_ops = {
.fault = xfs_filemap_fault,
.huge_fault = xfs_filemap_huge_fault,
.map_pages = xfs_filemap_map_pages,
.map_pages = filemap_map_pages,
.page_mkwrite = xfs_filemap_page_mkwrite,
.pfn_mkwrite = xfs_filemap_pfn_mkwrite,
};