From d5db0f97fbbeff11c88dec1aaf1536a975afbaeb Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Fri, 5 Feb 2010 22:59:53 +0000 Subject: [PATCH] xfs: more reserved blocks fixups This mangles the reserved blocks counts a little more. 1) add a helper function for the default reserved count 2) add helper functions to save/restore counts on ro/rw 3) save/restore reserved blocks on freeze/thaw 4) disallow changing reserved count while readonly V2: changed field name to match Dave's changes Signed-off-by: Eric Sandeen Signed-off-by: Alex Elder --- fs/xfs/linux-2.6/xfs_ioctl.c | 3 +++ fs/xfs/linux-2.6/xfs_super.c | 51 ++++++++++++++++++++++++++---------- fs/xfs/xfs_mount.c | 34 ++++++++++++++++-------- fs/xfs/xfs_mount.h | 1 + 4 files changed, 64 insertions(+), 25 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c index 3906e85abfdc..4ea1ee18aded 100644 --- a/fs/xfs/linux-2.6/xfs_ioctl.c +++ b/fs/xfs/linux-2.6/xfs_ioctl.c @@ -1431,6 +1431,9 @@ xfs_file_ioctl( if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (mp->m_flags & XFS_MOUNT_RDONLY) + return -XFS_ERROR(EROFS); + if (copy_from_user(&inout, arg, sizeof(inout))) return -XFS_ERROR(EFAULT); diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index e9c21454b9e2..6ce828e0e17b 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -1256,6 +1256,29 @@ xfs_fs_statfs( return 0; } +STATIC void +xfs_save_resvblks(struct xfs_mount *mp) +{ + __uint64_t resblks = 0; + + mp->m_resblks_save = mp->m_resblks; + xfs_reserve_blocks(mp, &resblks, NULL); +} + +STATIC void +xfs_restore_resvblks(struct xfs_mount *mp) +{ + __uint64_t resblks; + + if (mp->m_resblks_save) { + resblks = mp->m_resblks_save; + mp->m_resblks_save = 0; + } else + resblks = xfs_default_resblks(mp); + + xfs_reserve_blocks(mp, &resblks, NULL); +} + STATIC int xfs_fs_remount( struct super_block *sb, @@ -1318,8 +1341,6 @@ xfs_fs_remount( /* ro -> rw */ if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(*flags & MS_RDONLY)) { - __uint64_t resblks; - mp->m_flags &= ~XFS_MOUNT_RDONLY; if (mp->m_flags & XFS_MOUNT_BARRIER) xfs_mountfs_check_barriers(mp); @@ -1342,15 +1363,7 @@ xfs_fs_remount( * Fill out the reserve pool if it is empty. Use the stashed * value if it is non-zero, otherwise go with the default. */ - if (mp->m_resblks_save) { - resblks = mp->m_resblks_save; - mp->m_resblks_save = 0; - } else { - resblks = mp->m_sb.sb_dblocks; - do_div(resblks, 20); - resblks = min_t(__uint64_t, resblks, 1024); - } - xfs_reserve_blocks(mp, &resblks, NULL); + xfs_restore_resvblks(mp); } /* rw -> ro */ @@ -1363,11 +1376,9 @@ xfs_fs_remount( * so that if we get remounted rw, we can return it to the same * size. */ - __uint64_t resblks = 0; xfs_quiesce_data(mp); - mp->m_resblks_save = mp->m_resblks; - xfs_reserve_blocks(mp, &resblks, NULL); + xfs_save_resvblks(mp); xfs_quiesce_attr(mp); mp->m_flags |= XFS_MOUNT_RDONLY; } @@ -1386,10 +1397,21 @@ xfs_fs_freeze( { struct xfs_mount *mp = XFS_M(sb); + xfs_save_resvblks(mp); xfs_quiesce_attr(mp); return -xfs_fs_log_dummy(mp); } +STATIC int +xfs_fs_unfreeze( + struct super_block *sb) +{ + struct xfs_mount *mp = XFS_M(sb); + + xfs_restore_resvblks(mp); + return 0; +} + STATIC int xfs_fs_show_options( struct seq_file *m, @@ -1612,6 +1634,7 @@ static const struct super_operations xfs_super_operations = { .put_super = xfs_fs_put_super, .sync_fs = xfs_fs_sync_fs, .freeze_fs = xfs_fs_freeze, + .unfreeze_fs = xfs_fs_unfreeze, .statfs = xfs_fs_statfs, .remount_fs = xfs_fs_remount, .show_options = xfs_fs_show_options, diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 7f81ed72c875..5061149b2cc4 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -1091,6 +1091,22 @@ xfs_mount_reset_sbqflags( return xfs_trans_commit(tp, 0); } +__uint64_t +xfs_default_resblks(xfs_mount_t *mp) +{ + __uint64_t resblks; + + /* + * We default to 5% or 1024 fsbs of space reserved, whichever is smaller. + * This may drive us straight to ENOSPC on mount, but that implies + * we were already there on the last unmount. Warn if this occurs. + */ + resblks = mp->m_sb.sb_dblocks; + do_div(resblks, 20); + resblks = min_t(__uint64_t, resblks, 1024); + return resblks; +} + /* * This function does the following on an initial mount of a file system: * - reads the superblock from disk and init the mount struct @@ -1401,18 +1417,14 @@ xfs_mountfs( * when at ENOSPC. This is needed for operations like create with * attr, unwritten extent conversion at ENOSPC, etc. Data allocations * are not allowed to use this reserved space. - * - * We default to 5% or 1024 fsbs of space reserved, whichever is smaller. - * This may drive us straight to ENOSPC on mount, but that implies - * we were already there on the last unmount. Warn if this occurs. */ - resblks = mp->m_sb.sb_dblocks; - do_div(resblks, 20); - resblks = min_t(__uint64_t, resblks, 1024); - error = xfs_reserve_blocks(mp, &resblks, NULL); - if (error) - cmn_err(CE_WARN, "XFS: Unable to allocate reserve blocks. " - "Continuing without a reserve pool."); + if (!(mp->m_flags & XFS_MOUNT_RDONLY)) { + resblks = xfs_default_resblks(mp); + error = xfs_reserve_blocks(mp, &resblks, NULL); + if (error) + cmn_err(CE_WARN, "XFS: Unable to allocate reserve " + "blocks. Continuing without a reserve pool."); + } return 0; diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index 02d45f213e58..70504fcf14cd 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -421,6 +421,7 @@ typedef struct xfs_mod_sb { } xfs_mod_sb_t; extern int xfs_log_sbcount(xfs_mount_t *, uint); +extern __uint64_t xfs_default_resblks(xfs_mount_t *mp); extern int xfs_mountfs(xfs_mount_t *mp); extern void xfs_unmountfs(xfs_mount_t *);