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Message-Id: <1330963277-26336-12-git-send-email-jack@suse.cz>
Date: Mon, 5 Mar 2012 17:01:09 +0100
From: Jan Kara <jack@...e.cz>
To: LKML <linux-kernel@...r.kernel.org>
Cc: linux-fsdevel@...r.kernel.org, Al Viro <viro@...IV.linux.org.uk>,
Christoph Hellwig <hch@...radead.org>, dchinner@...hat.com,
sandeen@...hat.com, Kamal Mostafa <kamal@...onical.com>,
Jan Kara <jack@...e.cz>, Ben Myers <bpm@....com>,
Alex Elder <elder@...nel.org>, xfs@....sgi.com
Subject: [PATCH 11/19] xfs: Convert to new freezing code
Generic code now blocks all writers from standard write paths. So we block all
writers coming from ioctl and replace blocking of transactions on frozen
filesystem with a debugging check. As a bonus, we get a protection of ioctl
against racing remount read-only. We also convert xfs_file_aio_write() to a
non-racy freeze protection.
CC: Ben Myers <bpm@....com>
CC: Alex Elder <elder@...nel.org>
CC: xfs@....sgi.com
Signed-off-by: Jan Kara <jack@...e.cz>
---
fs/xfs/xfs_file.c | 10 ++++++--
fs/xfs/xfs_ioctl.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++--
fs/xfs/xfs_ioctl32.c | 12 ++++++++++
fs/xfs/xfs_iomap.c | 1 -
fs/xfs/xfs_mount.c | 2 +-
fs/xfs/xfs_mount.h | 3 --
fs/xfs/xfs_sync.c | 2 +-
fs/xfs/xfs_trans.c | 2 +-
8 files changed, 74 insertions(+), 13 deletions(-)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 7e5bc87..57dd20e 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -874,10 +874,12 @@ 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);
@@ -896,6 +898,8 @@ xfs_file_aio_write(
ret = err;
}
+out:
+ sb_end_write(inode->i_sb);
return ret;
}
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 76f3ca5..7890105 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -367,9 +367,15 @@ 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);
@@ -385,6 +391,7 @@ xfs_fssetdm_by_handle(
fsd.fsd_dmstate);
out:
+ mnt_drop_write_file(parfilp);
dput(dentry);
return error;
}
@@ -631,7 +638,11 @@ 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;
}
@@ -1160,6 +1171,7 @@ xfs_ioc_fssetxattr(
{
struct fsxattr fa;
unsigned int mask;
+ int error;
if (copy_from_user(&fa, arg, sizeof(fa)))
return -EFAULT;
@@ -1168,7 +1180,12 @@ 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
@@ -1193,6 +1210,7 @@ xfs_ioc_setxflags(
struct fsxattr fa;
unsigned int flags;
unsigned int mask;
+ int error;
if (copy_from_user(&flags, arg, sizeof(flags)))
return -EFAULT;
@@ -1207,7 +1225,12 @@ 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
@@ -1382,8 +1405,13 @@ 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;
}
@@ -1431,7 +1459,11 @@ 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;
}
@@ -1460,9 +1492,14 @@ 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;
@@ -1493,7 +1530,11 @@ 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;
}
@@ -1503,7 +1544,11 @@ 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;
}
@@ -1513,7 +1558,11 @@ 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;
}
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index f9ccb7b..2012369 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -602,7 +602,11 @@ 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: {
@@ -610,7 +614,11 @@ 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
@@ -629,7 +637,11 @@ 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:
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 246c7d5..7ab98d9 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -679,7 +679,6 @@ 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);
tp = _xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE, KM_NOFS);
tp->t_flags |= XFS_TRANS_RESERVE;
error = xfs_trans_reserve(tp, resblks,
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index d06afbc..bead529 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -1541,7 +1541,7 @@ 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));
}
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 19f69e2..f0afeb9 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -310,9 +310,6 @@ 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
*/
diff --git a/fs/xfs/xfs_sync.c b/fs/xfs/xfs_sync.c
index 40b75ee..c44d687 100644
--- a/fs/xfs/xfs_sync.c
+++ b/fs/xfs/xfs_sync.c
@@ -498,7 +498,7 @@ xfs_sync_worker(
if (!(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
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 329b06a..6468a2a 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -577,7 +577,6 @@ 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);
}
@@ -589,6 +588,7 @@ _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);
--
1.7.1
--
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