xfs: Convert to new freezing code

Generic code now blocks all writers from standard write paths. So we add
blocking of all writers coming from ioctl (we get a protection of ioctl against
racing remount read-only as a bonus) and convert xfs_file_aio_write() to a
non-racy freeze protection. We also keep freeze protection on transaction
start to block internal filesystem writes such as removal of preallocated
blocks.

CC: Ben Myers <bpm@sgi.com>
CC: Alex Elder <elder@kernel.org>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Jan Kara 2012-06-12 16:20:39 +02:00 committed by Al Viro
parent 8e8ad8a57c
commit d9457dc056
10 changed files with 109 additions and 16 deletions

View File

@ -123,6 +123,12 @@ xfs_setfilesize_trans_alloc(
ioend->io_append_trans = tp;
/*
* We will pass freeze protection with a transaction. So tell lockdep
* we released it.
*/
rwsem_release(&ioend->io_inode->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
1, _THIS_IP_);
/*
* We hand off the transaction to the completion thread now, so
* clear the flag here.
@ -199,6 +205,15 @@ xfs_end_io(
struct xfs_inode *ip = XFS_I(ioend->io_inode);
int error = 0;
if (ioend->io_append_trans) {
/*
* We've got freeze protection passed with the transaction.
* Tell lockdep about it.
*/
rwsem_acquire_read(
&ioend->io_inode->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
0, 1, _THIS_IP_);
}
if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
ioend->io_error = -EIO;
goto done;
@ -1410,6 +1425,9 @@ xfs_vm_direct_IO(
if (ioend->io_append_trans) {
current_set_flags_nested(&ioend->io_append_trans->t_pflags,
PF_FSTRANS);
rwsem_acquire_read(
&inode->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
0, 1, _THIS_IP_);
xfs_trans_cancel(ioend->io_append_trans, 0);
}
out_destroy_ioend:

View File

@ -781,10 +781,12 @@ xfs_file_aio_write(
if (ocount == 0)
return 0;
xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE);
sb_start_write(inode->i_sb);
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
return -EIO;
if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
ret = -EIO;
goto out;
}
if (unlikely(file->f_flags & O_DIRECT))
ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, ocount);
@ -803,6 +805,8 @@ xfs_file_aio_write(
ret = err;
}
out:
sb_end_write(inode->i_sb);
return ret;
}

View File

@ -364,9 +364,15 @@ xfs_fssetdm_by_handle(
if (copy_from_user(&dmhreq, arg, sizeof(xfs_fsop_setdm_handlereq_t)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(parfilp);
if (error)
return error;
dentry = xfs_handlereq_to_dentry(parfilp, &dmhreq.hreq);
if (IS_ERR(dentry))
if (IS_ERR(dentry)) {
mnt_drop_write_file(parfilp);
return PTR_ERR(dentry);
}
if (IS_IMMUTABLE(dentry->d_inode) || IS_APPEND(dentry->d_inode)) {
error = -XFS_ERROR(EPERM);
@ -382,6 +388,7 @@ xfs_fssetdm_by_handle(
fsd.fsd_dmstate);
out:
mnt_drop_write_file(parfilp);
dput(dentry);
return error;
}
@ -634,7 +641,11 @@ xfs_ioc_space(
if (ioflags & IO_INVIS)
attr_flags |= XFS_ATTR_DMI;
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_change_file_space(ip, cmd, bf, filp->f_pos, attr_flags);
mnt_drop_write_file(filp);
return -error;
}
@ -1163,6 +1174,7 @@ xfs_ioc_fssetxattr(
{
struct fsxattr fa;
unsigned int mask;
int error;
if (copy_from_user(&fa, arg, sizeof(fa)))
return -EFAULT;
@ -1171,7 +1183,12 @@ xfs_ioc_fssetxattr(
if (filp->f_flags & (O_NDELAY|O_NONBLOCK))
mask |= FSX_NONBLOCK;
return -xfs_ioctl_setattr(ip, &fa, mask);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_ioctl_setattr(ip, &fa, mask);
mnt_drop_write_file(filp);
return -error;
}
STATIC int
@ -1196,6 +1213,7 @@ xfs_ioc_setxflags(
struct fsxattr fa;
unsigned int flags;
unsigned int mask;
int error;
if (copy_from_user(&flags, arg, sizeof(flags)))
return -EFAULT;
@ -1210,7 +1228,12 @@ xfs_ioc_setxflags(
mask |= FSX_NONBLOCK;
fa.fsx_xflags = xfs_merge_ioc_xflags(flags, xfs_ip2xflags(ip));
return -xfs_ioctl_setattr(ip, &fa, mask);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_ioctl_setattr(ip, &fa, mask);
mnt_drop_write_file(filp);
return -error;
}
STATIC int
@ -1385,8 +1408,13 @@ xfs_file_ioctl(
if (copy_from_user(&dmi, arg, sizeof(dmi)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_set_dmattrs(ip, dmi.fsd_dmevmask,
dmi.fsd_dmstate);
mnt_drop_write_file(filp);
return -error;
}
@ -1434,7 +1462,11 @@ xfs_file_ioctl(
if (copy_from_user(&sxp, arg, sizeof(xfs_swapext_t)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_swapext(&sxp);
mnt_drop_write_file(filp);
return -error;
}
@ -1463,9 +1495,14 @@ xfs_file_ioctl(
if (copy_from_user(&inout, arg, sizeof(inout)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
/* input parameter is passed in resblks field of structure */
in = inout.resblks;
error = xfs_reserve_blocks(mp, &in, &inout);
mnt_drop_write_file(filp);
if (error)
return -error;
@ -1496,7 +1533,11 @@ xfs_file_ioctl(
if (copy_from_user(&in, arg, sizeof(in)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_growfs_data(mp, &in);
mnt_drop_write_file(filp);
return -error;
}
@ -1506,7 +1547,11 @@ xfs_file_ioctl(
if (copy_from_user(&in, arg, sizeof(in)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_growfs_log(mp, &in);
mnt_drop_write_file(filp);
return -error;
}
@ -1516,7 +1561,11 @@ xfs_file_ioctl(
if (copy_from_user(&in, arg, sizeof(in)))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_growfs_rt(mp, &in);
mnt_drop_write_file(filp);
return -error;
}

View File

@ -600,7 +600,11 @@ xfs_file_compat_ioctl(
if (xfs_compat_growfs_data_copyin(&in, arg))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_growfs_data(mp, &in);
mnt_drop_write_file(filp);
return -error;
}
case XFS_IOC_FSGROWFSRT_32: {
@ -608,7 +612,11 @@ xfs_file_compat_ioctl(
if (xfs_compat_growfs_rt_copyin(&in, arg))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_growfs_rt(mp, &in);
mnt_drop_write_file(filp);
return -error;
}
#endif
@ -627,7 +635,11 @@ xfs_file_compat_ioctl(
offsetof(struct xfs_swapext, sx_stat)) ||
xfs_ioctl32_bstat_copyin(&sxp.sx_stat, &sxu->sx_stat))
return -XFS_ERROR(EFAULT);
error = mnt_want_write_file(filp);
if (error)
return error;
error = xfs_swapext(&sxp);
mnt_drop_write_file(filp);
return -error;
}
case XFS_IOC_FSBULKSTAT_32:

View File

@ -680,9 +680,9 @@ xfs_iomap_write_unwritten(
* the same inode that we complete here and might deadlock
* on the iolock.
*/
xfs_wait_for_freeze(mp, SB_FREEZE_TRANS);
sb_start_intwrite(mp->m_super);
tp = _xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE, KM_NOFS);
tp->t_flags |= XFS_TRANS_RESERVE;
tp->t_flags |= XFS_TRANS_RESERVE | XFS_TRANS_FREEZE_PROT;
error = xfs_trans_reserve(tp, resblks,
XFS_WRITE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES,

View File

@ -1544,7 +1544,7 @@ xfs_unmountfs(
int
xfs_fs_writable(xfs_mount_t *mp)
{
return !(xfs_test_for_freeze(mp) || XFS_FORCED_SHUTDOWN(mp) ||
return !(mp->m_super->s_writers.frozen || XFS_FORCED_SHUTDOWN(mp) ||
(mp->m_flags & XFS_MOUNT_RDONLY));
}

View File

@ -314,9 +314,6 @@ void xfs_do_force_shutdown(struct xfs_mount *mp, int flags, char *fname,
#define SHUTDOWN_REMOTE_REQ 0x0010 /* shutdown came from remote cell */
#define SHUTDOWN_DEVICE_REQ 0x0020 /* failed all paths to the device */
#define xfs_test_for_freeze(mp) ((mp)->m_super->s_frozen)
#define xfs_wait_for_freeze(mp,l) vfs_check_frozen((mp)->m_super, (l))
/*
* Flags for xfs_mountfs
*/

View File

@ -394,7 +394,7 @@ xfs_sync_worker(
if (!(mp->m_super->s_flags & MS_ACTIVE) &&
!(mp->m_flags & XFS_MOUNT_RDONLY)) {
/* dgc: errors ignored here */
if (mp->m_super->s_frozen == SB_UNFROZEN &&
if (mp->m_super->s_writers.frozen == SB_UNFROZEN &&
xfs_log_need_covered(mp))
error = xfs_fs_log_dummy(mp);
else

View File

@ -576,8 +576,12 @@ xfs_trans_alloc(
xfs_mount_t *mp,
uint type)
{
xfs_wait_for_freeze(mp, SB_FREEZE_TRANS);
return _xfs_trans_alloc(mp, type, KM_SLEEP);
xfs_trans_t *tp;
sb_start_intwrite(mp->m_super);
tp = _xfs_trans_alloc(mp, type, KM_SLEEP);
tp->t_flags |= XFS_TRANS_FREEZE_PROT;
return tp;
}
xfs_trans_t *
@ -588,6 +592,7 @@ _xfs_trans_alloc(
{
xfs_trans_t *tp;
WARN_ON(mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
atomic_inc(&mp->m_active_trans);
tp = kmem_zone_zalloc(xfs_trans_zone, memflags);
@ -611,6 +616,8 @@ xfs_trans_free(
xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
atomic_dec(&tp->t_mountp->m_active_trans);
if (tp->t_flags & XFS_TRANS_FREEZE_PROT)
sb_end_intwrite(tp->t_mountp->m_super);
xfs_trans_free_dqinfo(tp);
kmem_zone_free(xfs_trans_zone, tp);
}
@ -643,7 +650,11 @@ xfs_trans_dup(
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(tp->t_ticket != NULL);
ntp->t_flags = XFS_TRANS_PERM_LOG_RES | (tp->t_flags & XFS_TRANS_RESERVE);
ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
(tp->t_flags & XFS_TRANS_RESERVE) |
(tp->t_flags & XFS_TRANS_FREEZE_PROT);
/* We gave our writer reference to the new transaction */
tp->t_flags &= ~XFS_TRANS_FREEZE_PROT;
ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
tp->t_blk_res = tp->t_blk_res_used;

View File

@ -179,6 +179,8 @@ struct xfs_log_item_desc {
#define XFS_TRANS_SYNC 0x08 /* make commit synchronous */
#define XFS_TRANS_DQ_DIRTY 0x10 /* at least one dquot in trx dirty */
#define XFS_TRANS_RESERVE 0x20 /* OK to use reserved data blocks */
#define XFS_TRANS_FREEZE_PROT 0x40 /* Transaction has elevated writer
count in superblock */
/*
* Values for call flags parameter.