Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'xfs-4.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"I've got one more bug fix for xfs for 4.17-rc4, which caps the amount
of data we try to handle in one dedupe request so that userspace can't
livelock the kernel.
This series has been run through a full xfstests run during the week
and through a quick xfstests run against this morning's master, with
no ajor failures reported.
Summary:
- Cap the maximum length of a deduplication request at MAX_RW_COUNT/2
to avoid kernel livelock due to excessively large IO requests"
* tag 'xfs-4.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: cap the length of deduplication requests
+10
+10
fs/xfs/xfs_file.c
+10
fs/xfs/xfs_file.c
···
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struct file *dst_file,
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u64 dst_loff)
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{
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+
struct inode *srci = file_inode(src_file);
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u64 max_dedupe;
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int error;
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+
/*
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* Since we have to read all these pages in to compare them, cut
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* it off at MAX_RW_COUNT/2 rounded down to the nearest block.
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* That means we won't do more than MAX_RW_COUNT IO per request.
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*/
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max_dedupe = (MAX_RW_COUNT >> 1) & ~(i_blocksize(srci) - 1);
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if (len > max_dedupe)
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len = max_dedupe;
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error = xfs_reflink_remap_range(src_file, loff, dst_file, dst_loff,
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len, true);
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if (error)