diff options
| author | Mark Johnston <markjdb@gmail.com> | 2022-01-21 19:54:05 +0000 |
|---|---|---|
| committer | Mark Johnston <markj@FreeBSD.org> | 2022-03-15 18:09:52 +0000 |
| commit | 9dc74c5a4b3d10b20d14ada2db605d73af8a33f0 (patch) | |
| tree | 6e908a020e98d9dc4b5a9d8bc0cd8c6352c34df6 | |
| parent | 0d1db5c3257e7cd1708b21dc4c6b14c9b1a41ec4 (diff) | |
Fix handling of errors from dmu_write_uio_dbuf() on FreeBSD
FreeBSD's implementation of zfs_uio_fault_move() returns EFAULT when a
page fault occurs while copying data in or out of user buffers. The VFS
treats such errors specially and will retry the I/O operation (which may
have made some partial progress).
When the FreeBSD and Linux implementations of zfs_write() were merged,
the handling of errors from dmu_write_uio_dbuf() changed such that
EFAULT is not handled as a partial write. For example, when appending
to a file, the z_size field of the znode is not updated after a partial
write resulting in EFAULT.
Restore the old handling of errors from dmu_write_uio_dbuf() to fix
this. This should have no impact on Linux, which has special handling
for EFAULT already.
Reviewed-by: Andriy Gapon <avg@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Closes #12964
(cherry picked from commit 063daa8350d4a78f96d1ee6550910363fd3756fb)
(cherry picked from commit b55a7f3422d76a6765716b2b6e78967bd75199c9)
Approved by: so
Security: FreeBSD-EN-22:10.zfs
| -rw-r--r-- | sys/contrib/openzfs/module/zfs/zfs_vnops.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/sys/contrib/openzfs/module/zfs/zfs_vnops.c b/sys/contrib/openzfs/module/zfs/zfs_vnops.c index 2dcc231b30b6..79128ed4b89f 100644 --- a/sys/contrib/openzfs/module/zfs/zfs_vnops.c +++ b/sys/contrib/openzfs/module/zfs/zfs_vnops.c @@ -316,7 +316,7 @@ out: int zfs_write(znode_t *zp, uio_t *uio, int ioflag, cred_t *cr) { - int error = 0; + int error = 0, error1; ssize_t start_resid = uio->uio_resid; /* @@ -551,7 +551,11 @@ zfs_write(znode_t *zp, uio_t *uio, int ioflag, cred_t *cr) continue; } #endif - if (error != 0) { + /* + * On FreeBSD, EFAULT should be propagated back to the + * VFS, which will handle faulting and will retry. + */ + if (error != 0 && error != EFAULT) { dmu_tx_commit(tx); break; } @@ -635,7 +639,7 @@ zfs_write(znode_t *zp, uio_t *uio, int ioflag, cred_t *cr) while ((end_size = zp->z_size) < uio->uio_loffset) { (void) atomic_cas_64(&zp->z_size, end_size, uio->uio_loffset); - ASSERT(error == 0); + ASSERT(error == 0 || error == EFAULT); } /* * If we are replaying and eof is non zero then force @@ -645,7 +649,10 @@ zfs_write(znode_t *zp, uio_t *uio, int ioflag, cred_t *cr) if (zfsvfs->z_replay && zfsvfs->z_replay_eof != 0) zp->z_size = zfsvfs->z_replay_eof; - error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx); + error1 = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx); + if (error1 != 0) + /* Avoid clobbering EFAULT. */ + error = error1; zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag, NULL, NULL); |