From: Ian Costello <ianc@sgi.com>
To: Eric Sandeen <sandeen@sandeen.net>
Cc: xfs-oss <xfs@oss.sgi.com>
Subject: Re: [PATCH, RFC] - remove mounpoint UUID code
Date: Sat, 08 Mar 2008 15:31:31 +1100 [thread overview]
Message-ID: <47D216A3.9040406@sgi.com> (raw)
In-Reply-To: <47D20F78.7000103@sandeen.net>
CXFS does use this to mount filesystems, i.e. on a client read the sb
get the uuid and use the uuid to lookup the MDS to request the mount...
Having said that if it is removed then it will force us to look at
another method to mount a cxfs filesystem, and also remove the necessity
for cxfs clients to not read the superblock (which is the only metadata
cxfs clients read off disk at this point)...
Regards,
--
Ian Costello Phone: +61 3 9963 1952
R&D Engineer Mobile: +61 417 508 522
CXFS MultiOS
Eric Sandeen wrote:
> It looks like all of the below is unused... and according
> to Nathan,
>
> "dont think it even got used/implemented anywhere, but i think it
> was meant to be an auto-mount kinda thing... such that when you look
> up at that point, it knows to mount the device with that uuid there,
> if its not already it was never really written anywhere ... just an
> idea in doug doucettes brain i think."
>
> Think it'll ever go anywhere, or should it get pruned?
>
> The below builds; not at all tested, until I get an idea if it's worth
> doing. Need to double check that some structures might not need padding
> out to keep things compatible/consistent...
>
> dmapi/xfs_dm.c | 2 --
> xfs_attr_leaf.c | 6 +-----
> xfs_bmap.c | 4 ----
> xfs_dinode.h | 2 --
> xfs_inode.c | 8 --------
> xfs_inode.h | 1 -
> xfs_inode_item.c | 53 +++++++++++------------------------------------------
> xfs_inode_item.h | 26 ++++++++------------------
> xfs_itable.c | 2 --
> xfs_log_recover.c | 10 ++--------
> xfsidbg.c | 2 +-
> 11 files changed, 23 insertions(+), 93 deletions(-)
>
>
> Index: linux-2.6-xfs/fs/xfs/dmapi/xfs_dm.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/dmapi/xfs_dm.c
> +++ linux-2.6-xfs/fs/xfs/dmapi/xfs_dm.c
> @@ -363,7 +363,6 @@ xfs_dip_to_stat(
> buf->dt_blocks = 0;
> break;
> case XFS_DINODE_FMT_LOCAL:
> - case XFS_DINODE_FMT_UUID:
> buf->dt_rdev = 0;
> buf->dt_blksize = mp->m_sb.sb_blocksize;
> buf->dt_blocks = 0;
> @@ -431,7 +430,6 @@ xfs_ip_to_stat(
> buf->dt_blocks = 0;
> break;
> case XFS_DINODE_FMT_LOCAL:
> - case XFS_DINODE_FMT_UUID:
> buf->dt_rdev = 0;
> buf->dt_blksize = mp->m_sb.sb_blocksize;
> buf->dt_blocks = 0;
> Index: linux-2.6-xfs/fs/xfs/xfs_attr_leaf.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_attr_leaf.c
> +++ linux-2.6-xfs/fs/xfs/xfs_attr_leaf.c
> @@ -155,13 +155,9 @@ xfs_attr_shortform_bytesfit(xfs_inode_t
>
> offset = (XFS_LITINO(mp) - bytes) >> 3; /* rounded down */
>
> - switch (dp->i_d.di_format) {
> - case XFS_DINODE_FMT_DEV:
> + if (dp->i_d.di_format == XFS_DINODE_FMT_DEV) {
> minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
> return (offset >= minforkoff) ? minforkoff : 0;
> - case XFS_DINODE_FMT_UUID:
> - minforkoff = roundup(sizeof(uuid_t), 8) >> 3;
> - return (offset >= minforkoff) ? minforkoff : 0;
> }
>
> if (!(mp->m_flags & XFS_MOUNT_ATTR2)) {
> Index: linux-2.6-xfs/fs/xfs/xfs_bmap.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_bmap.c
> +++ linux-2.6-xfs/fs/xfs/xfs_bmap.c
> @@ -3532,7 +3532,6 @@ xfs_bmap_forkoff_reset(
> {
> if (whichfork == XFS_ATTR_FORK &&
> (ip->i_d.di_format != XFS_DINODE_FMT_DEV) &&
> - (ip->i_d.di_format != XFS_DINODE_FMT_UUID) &&
> (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
> ((mp->m_attroffset >> 3) > ip->i_d.di_forkoff)) {
> ip->i_d.di_forkoff = mp->m_attroffset >> 3;
> @@ -4000,9 +3999,6 @@ xfs_bmap_add_attrfork(
> case XFS_DINODE_FMT_DEV:
> ip->i_d.di_forkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
> break;
> - case XFS_DINODE_FMT_UUID:
> - ip->i_d.di_forkoff = roundup(sizeof(uuid_t), 8) >> 3;
> - break;
> case XFS_DINODE_FMT_LOCAL:
> case XFS_DINODE_FMT_EXTENTS:
> case XFS_DINODE_FMT_BTREE:
> Index: linux-2.6-xfs/fs/xfs/xfs_dinode.h
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_dinode.h
> +++ linux-2.6-xfs/fs/xfs/xfs_dinode.h
> @@ -88,7 +88,6 @@ typedef struct xfs_dinode
> xfs_dir2_sf_t di_dir2sf; /* shortform directory v2 */
> char di_c[1]; /* local contents */
> __be32 di_dev; /* device for S_IFCHR/S_IFBLK */
> - uuid_t di_muuid; /* mount point value */
> char di_symlink[1]; /* local symbolic link */
> } di_u;
> union {
> @@ -150,7 +149,6 @@ typedef enum xfs_dinode_fmt
> /* LNK: di_symlink */
> XFS_DINODE_FMT_EXTENTS, /* DIR, REG, LNK: di_bmx */
> XFS_DINODE_FMT_BTREE, /* DIR, REG, LNK: di_bmbt */
> - XFS_DINODE_FMT_UUID /* MNT: di_uuid */
> } xfs_dinode_fmt_t;
>
> /*
> Index: linux-2.6-xfs/fs/xfs/xfs_inode.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_inode.c
> +++ linux-2.6-xfs/fs/xfs/xfs_inode.c
> @@ -2970,14 +2970,6 @@ xfs_iflush_fork(
> }
> break;
>
> - case XFS_DINODE_FMT_UUID:
> - if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
> - ASSERT(whichfork == XFS_DATA_FORK);
> - memcpy(&dip->di_u.di_muuid, &ip->i_df.if_u2.if_uuid,
> - sizeof(uuid_t));
> - }
> - break;
> -
> default:
> ASSERT(0);
> break;
> Index: linux-2.6-xfs/fs/xfs/xfs_inode_item.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_inode_item.c
> +++ linux-2.6-xfs/fs/xfs/xfs_inode_item.c
> @@ -70,8 +70,7 @@ xfs_inode_item_size(
> switch (ip->i_d.di_format) {
> case XFS_DINODE_FMT_EXTENTS:
> iip->ili_format.ilf_fields &=
> - ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID);
> + ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT | XFS_ILOG_DEV);
> if ((iip->ili_format.ilf_fields & XFS_ILOG_DEXT) &&
> (ip->i_d.di_nextents > 0) &&
> (ip->i_df.if_bytes > 0)) {
> @@ -86,8 +85,7 @@ xfs_inode_item_size(
> ASSERT(ip->i_df.if_ext_max ==
> XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t));
> iip->ili_format.ilf_fields &=
> - ~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID);
> + ~(XFS_ILOG_DDATA | XFS_ILOG_DEXT | XFS_ILOG_DEV);
> if ((iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) &&
> (ip->i_df.if_broot_bytes > 0)) {
> ASSERT(ip->i_df.if_broot != NULL);
> @@ -112,8 +110,7 @@ xfs_inode_item_size(
>
> case XFS_DINODE_FMT_LOCAL:
> iip->ili_format.ilf_fields &=
> - ~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID);
> + ~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT | XFS_ILOG_DEV);
> if ((iip->ili_format.ilf_fields & XFS_ILOG_DDATA) &&
> (ip->i_df.if_bytes > 0)) {
> ASSERT(ip->i_df.if_u1.if_data != NULL);
> @@ -126,14 +123,7 @@ xfs_inode_item_size(
>
> case XFS_DINODE_FMT_DEV:
> iip->ili_format.ilf_fields &=
> - ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
> - XFS_ILOG_DEXT | XFS_ILOG_UUID);
> - break;
> -
> - case XFS_DINODE_FMT_UUID:
> - iip->ili_format.ilf_fields &=
> - ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
> - XFS_ILOG_DEXT | XFS_ILOG_DEV);
> + ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT | XFS_ILOG_DEXT);
> break;
>
> default:
> @@ -319,8 +309,7 @@ xfs_inode_item_format(
> switch (ip->i_d.di_format) {
> case XFS_DINODE_FMT_EXTENTS:
> ASSERT(!(iip->ili_format.ilf_fields &
> - (XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID)));
> + (XFS_ILOG_DDATA | XFS_ILOG_DBROOT | XFS_ILOG_DEV)));
> if (iip->ili_format.ilf_fields & XFS_ILOG_DEXT) {
> ASSERT(ip->i_df.if_bytes > 0);
> ASSERT(ip->i_df.if_u1.if_extents != NULL);
> @@ -369,8 +358,7 @@ xfs_inode_item_format(
>
> case XFS_DINODE_FMT_BTREE:
> ASSERT(!(iip->ili_format.ilf_fields &
> - (XFS_ILOG_DDATA | XFS_ILOG_DEXT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID)));
> + (XFS_ILOG_DDATA | XFS_ILOG_DEXT | XFS_ILOG_DEV)));
> if (iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) {
> ASSERT(ip->i_df.if_broot_bytes > 0);
> ASSERT(ip->i_df.if_broot != NULL);
> @@ -385,8 +373,7 @@ xfs_inode_item_format(
>
> case XFS_DINODE_FMT_LOCAL:
> ASSERT(!(iip->ili_format.ilf_fields &
> - (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
> - XFS_ILOG_DEV | XFS_ILOG_UUID)));
> + (XFS_ILOG_DBROOT | XFS_ILOG_DEXT | XFS_ILOG_DEV)));
> if (iip->ili_format.ilf_fields & XFS_ILOG_DDATA) {
> ASSERT(ip->i_df.if_bytes > 0);
> ASSERT(ip->i_df.if_u1.if_data != NULL);
> @@ -411,21 +398,9 @@ xfs_inode_item_format(
>
> case XFS_DINODE_FMT_DEV:
> ASSERT(!(iip->ili_format.ilf_fields &
> - (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
> - XFS_ILOG_DDATA | XFS_ILOG_UUID)));
> + (XFS_ILOG_DBROOT | XFS_ILOG_DEXT | XFS_ILOG_DDATA)));
> if (iip->ili_format.ilf_fields & XFS_ILOG_DEV) {
> - iip->ili_format.ilf_u.ilfu_rdev =
> - ip->i_df.if_u2.if_rdev;
> - }
> - break;
> -
> - case XFS_DINODE_FMT_UUID:
> - ASSERT(!(iip->ili_format.ilf_fields &
> - (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
> - XFS_ILOG_DDATA | XFS_ILOG_DEV)));
> - if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
> - iip->ili_format.ilf_u.ilfu_uuid =
> - ip->i_df.if_u2.if_uuid;
> + iip->ili_format.ilf_rdev = ip->i_df.if_u2.if_rdev;
> }
> break;
>
> @@ -1088,10 +1063,7 @@ xfs_inode_item_format_convert(
> in_f->ilf_asize = in_f32->ilf_asize;
> in_f->ilf_dsize = in_f32->ilf_dsize;
> in_f->ilf_ino = in_f32->ilf_ino;
> - /* copy biggest field of ilf_u */
> - memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
> - in_f32->ilf_u.ilfu_uuid.__u_bits,
> - sizeof(uuid_t));
> + in_f->ilf_rdev = in_f32->ilf_rdev;
> in_f->ilf_blkno = in_f32->ilf_blkno;
> in_f->ilf_len = in_f32->ilf_len;
> in_f->ilf_boffset = in_f32->ilf_boffset;
> @@ -1106,10 +1078,7 @@ xfs_inode_item_format_convert(
> in_f->ilf_asize = in_f64->ilf_asize;
> in_f->ilf_dsize = in_f64->ilf_dsize;
> in_f->ilf_ino = in_f64->ilf_ino;
> - /* copy biggest field of ilf_u */
> - memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
> - in_f64->ilf_u.ilfu_uuid.__u_bits,
> - sizeof(uuid_t));
> + in_f->ilf_rdev = in_f64->ilf_rdev;
> in_f->ilf_blkno = in_f64->ilf_blkno;
> in_f->ilf_len = in_f64->ilf_len;
> in_f->ilf_boffset = in_f64->ilf_boffset;
> Index: linux-2.6-xfs/fs/xfs/xfs_itable.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_itable.c
> +++ linux-2.6-xfs/fs/xfs/xfs_itable.c
> @@ -111,7 +111,6 @@ xfs_bulkstat_one_iget(
> buf->bs_blocks = 0;
> break;
> case XFS_DINODE_FMT_LOCAL:
> - case XFS_DINODE_FMT_UUID:
> buf->bs_rdev = 0;
> buf->bs_blksize = mp->m_sb.sb_blocksize;
> buf->bs_blocks = 0;
> @@ -186,7 +185,6 @@ xfs_bulkstat_one_dinode(
> buf->bs_blocks = 0;
> break;
> case XFS_DINODE_FMT_LOCAL:
> - case XFS_DINODE_FMT_UUID:
> buf->bs_rdev = 0;
> buf->bs_blksize = mp->m_sb.sb_blocksize;
> buf->bs_blocks = 0;
> Index: linux-2.6-xfs/fs/xfs/xfs_inode_item.h
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_inode_item.h
> +++ linux-2.6-xfs/fs/xfs/xfs_inode_item.h
> @@ -31,10 +31,7 @@ typedef struct xfs_inode_log_format {
> __uint16_t ilf_asize; /* size of attr d/ext/root */
> __uint16_t ilf_dsize; /* size of data/ext/root */
> __uint64_t ilf_ino; /* inode number */
> - union {
> - __uint32_t ilfu_rdev; /* rdev value for dev inode*/
> - uuid_t ilfu_uuid; /* mount point value */
> - } ilf_u;
> + __uint32_t ilf_rdev; /* rdev value for dev inode*/
> __int64_t ilf_blkno; /* blkno of inode buffer */
> __int32_t ilf_len; /* len of inode buffer */
> __int32_t ilf_boffset; /* off of inode in buffer */
> @@ -48,10 +45,7 @@ typedef struct xfs_inode_log_format_32 {
> __uint16_t ilf_asize; /* size of attr d/ext/root */
> __uint16_t ilf_dsize; /* size of data/ext/root */
> __uint64_t ilf_ino; /* inode number */
> - union {
> - __uint32_t ilfu_rdev; /* rdev value for dev inode*/
> - uuid_t ilfu_uuid; /* mount point value */
> - } ilf_u;
> + __uint32_t ilf_rdev; /* rdev value for dev inode*/
> __int64_t ilf_blkno; /* blkno of inode buffer */
> __int32_t ilf_len; /* len of inode buffer */
> __int32_t ilf_boffset; /* off of inode in buffer */
> @@ -66,10 +60,7 @@ typedef struct xfs_inode_log_format_64 {
> __uint16_t ilf_dsize; /* size of data/ext/root */
> __uint32_t ilf_pad; /* pad for 64 bit boundary */
> __uint64_t ilf_ino; /* inode number */
> - union {
> - __uint32_t ilfu_rdev; /* rdev value for dev inode*/
> - uuid_t ilfu_uuid; /* mount point value */
> - } ilf_u;
> + __uint32_t ilf_rdev; /* rdev value for dev inode*/
> __int64_t ilf_blkno; /* blkno of inode buffer */
> __int32_t ilf_len; /* len of inode buffer */
> __int32_t ilf_boffset; /* off of inode in buffer */
> @@ -83,15 +74,15 @@ typedef struct xfs_inode_log_format_64 {
> #define XFS_ILOG_DEXT 0x004 /* log i_df.if_extents */
> #define XFS_ILOG_DBROOT 0x008 /* log i_df.i_broot */
> #define XFS_ILOG_DEV 0x010 /* log the dev field */
> -#define XFS_ILOG_UUID 0x020 /* log the uuid field */
> +/* 0x020*/ /* unused */
> #define XFS_ILOG_ADATA 0x040 /* log i_af.if_data */
> #define XFS_ILOG_AEXT 0x080 /* log i_af.if_extents */
> #define XFS_ILOG_ABROOT 0x100 /* log i_af.i_broot */
>
> #define XFS_ILOG_NONCORE (XFS_ILOG_DDATA | XFS_ILOG_DEXT | \
> XFS_ILOG_DBROOT | XFS_ILOG_DEV | \
> - XFS_ILOG_UUID | XFS_ILOG_ADATA | \
> - XFS_ILOG_AEXT | XFS_ILOG_ABROOT)
> + XFS_ILOG_ADATA | XFS_ILOG_AEXT | \
> + XFS_ILOG_ABROOT)
>
> #define XFS_ILOG_DFORK (XFS_ILOG_DDATA | XFS_ILOG_DEXT | \
> XFS_ILOG_DBROOT)
> @@ -101,9 +92,8 @@ typedef struct xfs_inode_log_format_64 {
>
> #define XFS_ILOG_ALL (XFS_ILOG_CORE | XFS_ILOG_DDATA | \
> XFS_ILOG_DEXT | XFS_ILOG_DBROOT | \
> - XFS_ILOG_DEV | XFS_ILOG_UUID | \
> - XFS_ILOG_ADATA | XFS_ILOG_AEXT | \
> - XFS_ILOG_ABROOT)
> + XFS_ILOG_DEV | XFS_ILOG_ADATA | \
> + XFS_ILOG_AEXT | XFS_ILOG_ABROOT)
>
> #define XFS_ILI_HOLD 0x1
> #define XFS_ILI_IOLOCKED_EXCL 0x2
> Index: linux-2.6-xfs/fs/xfs/xfs_log_recover.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_log_recover.c
> +++ linux-2.6-xfs/fs/xfs/xfs_log_recover.c
> @@ -2420,14 +2420,8 @@ xlog_recover_do_inode_trans(
> }
>
> fields = in_f->ilf_fields;
> - switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) {
> - case XFS_ILOG_DEV:
> - dip->di_u.di_dev = cpu_to_be32(in_f->ilf_u.ilfu_rdev);
> - break;
> - case XFS_ILOG_UUID:
> - dip->di_u.di_muuid = in_f->ilf_u.ilfu_uuid;
> - break;
> - }
> + if (fields & XFS_ILOG_DEV)
> + dip->di_u.di_dev = cpu_to_be32(in_f->ilf_rdev);
>
> if (in_f->ilf_size == 2)
> goto write_inode_buffer;
> Index: linux-2.6-xfs/fs/xfs/xfsidbg.c
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfsidbg.c
> +++ linux-2.6-xfs/fs/xfs/xfsidbg.c
> @@ -3424,7 +3424,7 @@ xfs_inode_item_print(xfs_inode_log_item_
> kdb_printf("dsize %d, asize %d, rdev 0x%x\n",
> ilip->ili_format.ilf_dsize,
> ilip->ili_format.ilf_asize,
> - ilip->ili_format.ilf_u.ilfu_rdev);
> + ilip->ili_format.ilf_rdev);
> kdb_printf("blkno 0x%Lx len 0x%x boffset 0x%x\n",
> ilip->ili_format.ilf_blkno,
> ilip->ili_format.ilf_len,
> Index: linux-2.6-xfs/fs/xfs/xfs_inode.h
> ===================================================================
> --- linux-2.6-xfs.orig/fs/xfs/xfs_inode.h
> +++ linux-2.6-xfs/fs/xfs/xfs_inode.h
> @@ -79,7 +79,6 @@ typedef struct xfs_ifork {
> char if_inline_data[XFS_INLINE_DATA];
> /* very small file data */
> xfs_dev_t if_rdev; /* dev number if special */
> - uuid_t if_uuid; /* mount point value */
> } if_u2;
> } xfs_ifork_t;
>
>
>
>
>
next prev parent reply other threads:[~2008-03-08 4:31 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-08 4:00 [PATCH, RFC] - remove mounpoint UUID code Eric Sandeen
2008-03-08 4:31 ` Ian Costello [this message]
2008-03-08 4:33 ` Eric Sandeen
2008-03-08 4:40 ` Ian Costello
2008-03-08 4:59 ` Eric Sandeen
2008-03-08 11:54 ` Christoph Hellwig
2008-03-11 0:44 ` Nathan Scott
2008-03-11 1:19 ` Eric Sandeen
2008-03-11 20:09 ` nscott
2008-03-12 7:22 ` Christoph Hellwig
2008-07-08 3:09 ` [PATCH, RFC] - remove mountpoint " Eric Sandeen
2008-07-25 2:22 ` [PATCH, RFC] - remove mounpoint " Niv Sardi
2008-07-25 3:11 ` Eric Sandeen
2008-07-25 5:12 ` Niv Sardi
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