xfs: fallback to vmalloc for large buffers in xfs_attrmulti_attr_get

xfsdump uses for a large buffer for extended attributes, which has a
kmalloc'd shadow buffer in the kernel. This can fail after the
system has been running for some time as it is a high order
allocation. Add a fallback to vmalloc so that it doesn't require
contiguous memory and so won't randomly fail while xfsdump is
running.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
This commit is contained in:
Dave Chinner 2012-03-07 04:50:21 +00:00 committed by Ben Myers
parent 6eb2466036
commit ad650f5b27

View File

@ -450,9 +450,12 @@ xfs_attrmulti_attr_get(
if (*len > XATTR_SIZE_MAX)
return EINVAL;
kbuf = kmalloc(*len, GFP_KERNEL);
if (!kbuf)
return ENOMEM;
kbuf = kmem_zalloc(*len, KM_SLEEP | KM_MAYFAIL);
if (!kbuf) {
kbuf = kmem_zalloc_large(*len);
if (!kbuf)
return ENOMEM;
}
error = xfs_attr_get(XFS_I(inode), name, kbuf, (int *)len, flags);
if (error)
@ -462,7 +465,10 @@ xfs_attrmulti_attr_get(
error = EFAULT;
out_kfree:
kfree(kbuf);
if (is_vmalloc_addr(kbuf))
kmem_free_large(kbuf);
else
kmem_free(kbuf);
return error;
}