PATCH V2] more reserved blocks fixups
Alex Elder
aelder at sgi.com
Fri Feb 5 19:41:15 CST 2010
On Fri, 2010-02-05 at 16:59 -0600, Eric Sandeen wrote:
> 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
Looks good. Thanks for updating it.
> Signed-off-by: Eric Sandeen <sandeen at sandeen.net>
Reviewed-by: Alex Elder <aelder at sgi.com>
> ---
>
> V2: changed field name to match Dave's changes
>
> diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
> index a034cf6..883929b 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 8884f26..97c0f5a 100644
> --- a/fs/xfs/linux-2.6/xfs_super.c
> +++ b/fs/xfs/linux-2.6/xfs_super.c
> @@ -1257,6 +1257,29 @@ 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,
> @@ -1319,8 +1342,6 @@ 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);
> @@ -1343,15 +1364,7 @@ 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 */
> @@ -1364,11 +1377,9 @@ 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;
> }
> @@ -1387,11 +1398,22 @@ 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,
> struct vfsmount *mnt)
> @@ -1613,6 +1635,7 @@ 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 eb403b4..48e1ee7 100644
> --- a/fs/xfs/xfs_mount.c
> +++ b/fs/xfs/xfs_mount.c
> @@ -1008,6 +1008,22 @@ 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
> @@ -1318,18 +1334,14 @@ 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 996273d..c8f880d 100644
> --- a/fs/xfs/xfs_mount.h
> +++ b/fs/xfs/xfs_mount.h
> @@ -429,6 +429,7 @@ 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 *);
>
> _______________________________________________
> xfs mailing list
> xfs at oss.sgi.com
> http://oss.sgi.com/mailman/listinfo/xfs
More information about the xfs
mailing list