From d9457dc056249913a7abe8b71dc09e427e590e35 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 12 Jun 2012 16:20:39 +0200 Subject: [PATCH] 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 CC: Alex Elder CC: xfs@oss.sgi.com Signed-off-by: Jan Kara Signed-off-by: Al Viro --- fs/xfs/xfs_aops.c | 18 +++++++++++++++ fs/xfs/xfs_file.c | 10 +++++--- fs/xfs/xfs_ioctl.c | 55 +++++++++++++++++++++++++++++++++++++++++--- fs/xfs/xfs_ioctl32.c | 12 ++++++++++ fs/xfs/xfs_iomap.c | 4 ++-- fs/xfs/xfs_mount.c | 2 +- fs/xfs/xfs_mount.h | 3 --- fs/xfs/xfs_sync.c | 2 +- fs/xfs/xfs_trans.c | 17 +++++++++++--- fs/xfs/xfs_trans.h | 2 ++ 10 files changed, 109 insertions(+), 16 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 8dad722c0041..daa42383ebd9 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -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 @@ out_trans_cancel: 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: diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 9f7ec15a6522..f0081f20e5c0 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -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; } diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 1f1535d25a9b..0e0232c3b6d9 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -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; } diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index c4f2da0d2bf5..1244274a5674 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -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: diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index aadfce6681ee..b3b9b26091a3 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -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, diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 536021fb3d4e..b09a4a7eb640 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -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)); } diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index 90c1fc9eaea4..c6bca0d92cb1 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -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 */ diff --git a/fs/xfs/xfs_sync.c b/fs/xfs/xfs_sync.c index 1e9ee064dbb2..0b9feacdcd1f 100644 --- a/fs/xfs/xfs_sync.c +++ b/fs/xfs/xfs_sync.c @@ -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 diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index fdf324508c5e..06ed520a767f 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -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; diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 7c37b533aa8e..19c174282878 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -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. -- 2.20.1