From 27174203f570b923e5c02c618a5557295bab8755 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 30 Mar 2009 10:21:31 +0200 Subject: xfs: cleanup uuid handling The uuid table handling should not be part of a semi-generic uuid library but in the XFS code using it, so move those bits to xfs_mount.c and refactor the whole glob to make it a proper abstraction. Signed-off-by: Christoph Hellwig Reviewed-by: Felix Blyakher --- fs/xfs/support/uuid.c | 71 ----------------------------- fs/xfs/support/uuid.h | 4 -- fs/xfs/xfs_mount.c | 124 +++++++++++++++++++++++++++++++++----------------- 3 files changed, 83 insertions(+), 116 deletions(-) diff --git a/fs/xfs/support/uuid.c b/fs/xfs/support/uuid.c index 5830c040ea7e..b83f76b6d410 100644 --- a/fs/xfs/support/uuid.c +++ b/fs/xfs/support/uuid.c @@ -17,10 +17,6 @@ */ #include -static DEFINE_MUTEX(uuid_monitor); -static int uuid_table_size; -static uuid_t *uuid_table; - /* IRIX interpretation of an uuid_t */ typedef struct { __be32 uu_timelow; @@ -46,12 +42,6 @@ uuid_getnodeuniq(uuid_t *uuid, int fsid [2]) fsid[1] = be32_to_cpu(uup->uu_timelow); } -void -uuid_create_nil(uuid_t *uuid) -{ - memset(uuid, 0, sizeof(*uuid)); -} - int uuid_is_nil(uuid_t *uuid) { @@ -71,64 +61,3 @@ uuid_equal(uuid_t *uuid1, uuid_t *uuid2) { return memcmp(uuid1, uuid2, sizeof(uuid_t)) ? 0 : 1; } - -/* - * Given a 128-bit uuid, return a 64-bit value by adding the top and bottom - * 64-bit words. NOTE: This function can not be changed EVER. Although - * brain-dead, some applications depend on this 64-bit value remaining - * persistent. Specifically, DMI vendors store the value as a persistent - * filehandle. - */ -__uint64_t -uuid_hash64(uuid_t *uuid) -{ - __uint64_t *sp = (__uint64_t *)uuid; - - return sp[0] + sp[1]; -} - -int -uuid_table_insert(uuid_t *uuid) -{ - int i, hole; - - mutex_lock(&uuid_monitor); - for (i = 0, hole = -1; i < uuid_table_size; i++) { - if (uuid_is_nil(&uuid_table[i])) { - hole = i; - continue; - } - if (uuid_equal(uuid, &uuid_table[i])) { - mutex_unlock(&uuid_monitor); - return 0; - } - } - if (hole < 0) { - uuid_table = kmem_realloc(uuid_table, - (uuid_table_size + 1) * sizeof(*uuid_table), - uuid_table_size * sizeof(*uuid_table), - KM_SLEEP); - hole = uuid_table_size++; - } - uuid_table[hole] = *uuid; - mutex_unlock(&uuid_monitor); - return 1; -} - -void -uuid_table_remove(uuid_t *uuid) -{ - int i; - - mutex_lock(&uuid_monitor); - for (i = 0; i < uuid_table_size; i++) { - if (uuid_is_nil(&uuid_table[i])) - continue; - if (!uuid_equal(uuid, &uuid_table[i])) - continue; - uuid_create_nil(&uuid_table[i]); - break; - } - ASSERT(i < uuid_table_size); - mutex_unlock(&uuid_monitor); -} diff --git a/fs/xfs/support/uuid.h b/fs/xfs/support/uuid.h index cff5b607d445..4732d71262cc 100644 --- a/fs/xfs/support/uuid.h +++ b/fs/xfs/support/uuid.h @@ -22,12 +22,8 @@ typedef struct { unsigned char __u_bits[16]; } uuid_t; -extern void uuid_create_nil(uuid_t *uuid); extern int uuid_is_nil(uuid_t *uuid); extern int uuid_equal(uuid_t *uuid1, uuid_t *uuid2); extern void uuid_getnodeuniq(uuid_t *uuid, int fsid [2]); -extern __uint64_t uuid_hash64(uuid_t *uuid); -extern int uuid_table_insert(uuid_t *uuid); -extern void uuid_table_remove(uuid_t *uuid); #endif /* __XFS_SUPPORT_UUID_H__ */ diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 92fedfcc879a..b101990df027 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -45,7 +45,6 @@ #include "xfs_fsops.h" #include "xfs_utils.h" -STATIC int xfs_uuid_mount(xfs_mount_t *); STATIC void xfs_unmountfs_wait(xfs_mount_t *); @@ -121,6 +120,84 @@ static const struct { { sizeof(xfs_sb_t), 0 } }; +static DEFINE_MUTEX(xfs_uuid_table_mutex); +static int xfs_uuid_table_size; +static uuid_t *xfs_uuid_table; + +/* + * See if the UUID is unique among mounted XFS filesystems. + * Mount fails if UUID is nil or a FS with the same UUID is already mounted. + */ +STATIC int +xfs_uuid_mount( + struct xfs_mount *mp) +{ + uuid_t *uuid = &mp->m_sb.sb_uuid; + int hole, i; + + if (mp->m_flags & XFS_MOUNT_NOUUID) + return 0; + + if (uuid_is_nil(uuid)) { + cmn_err(CE_WARN, + "XFS: Filesystem %s has nil UUID - can't mount", + mp->m_fsname); + return XFS_ERROR(EINVAL); + } + + mutex_lock(&xfs_uuid_table_mutex); + for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) { + if (uuid_is_nil(&xfs_uuid_table[i])) { + hole = i; + continue; + } + if (uuid_equal(uuid, &xfs_uuid_table[i])) + goto out_duplicate; + } + + if (hole < 0) { + xfs_uuid_table = kmem_realloc(xfs_uuid_table, + (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table), + xfs_uuid_table_size * sizeof(*xfs_uuid_table), + KM_SLEEP); + hole = xfs_uuid_table_size++; + } + xfs_uuid_table[hole] = *uuid; + mutex_unlock(&xfs_uuid_table_mutex); + + return 0; + + out_duplicate: + mutex_unlock(&xfs_uuid_table_mutex); + cmn_err(CE_WARN, "XFS: Filesystem %s has duplicate UUID - can't mount", + mp->m_fsname); + return XFS_ERROR(EINVAL); +} + +STATIC void +xfs_uuid_unmount( + struct xfs_mount *mp) +{ + uuid_t *uuid = &mp->m_sb.sb_uuid; + int i; + + if (mp->m_flags & XFS_MOUNT_NOUUID) + return; + + mutex_lock(&xfs_uuid_table_mutex); + for (i = 0; i < xfs_uuid_table_size; i++) { + if (uuid_is_nil(&xfs_uuid_table[i])) + continue; + if (!uuid_equal(uuid, &xfs_uuid_table[i])) + continue; + memset(&xfs_uuid_table[i], 0, sizeof(uuid_t)); + break; + } + ASSERT(i < xfs_uuid_table_size); + mutex_unlock(&xfs_uuid_table_mutex); +} + + /* * Free up the resources associated with a mount structure. Assume that * the structure was initially zeroed, so we can tell which fields got @@ -962,18 +1039,9 @@ xfs_mountfs( mp->m_maxioffset = xfs_max_file_offset(sbp->sb_blocklog); - /* - * XFS uses the uuid from the superblock as the unique - * identifier for fsid. We can not use the uuid from the volume - * since a single partition filesystem is identical to a single - * partition volume/filesystem. - */ - if (!(mp->m_flags & XFS_MOUNT_NOUUID)) { - if (xfs_uuid_mount(mp)) { - error = XFS_ERROR(EINVAL); - goto out; - } - } + error = xfs_uuid_mount(mp); + if (error) + goto out; /* * Set the minimum read and write sizes @@ -1192,8 +1260,7 @@ xfs_mountfs( out_free_perag: xfs_free_perag(mp); out_remove_uuid: - if (!(mp->m_flags & XFS_MOUNT_NOUUID)) - uuid_table_remove(&mp->m_sb.sb_uuid); + xfs_uuid_unmount(mp); out: return error; } @@ -1276,9 +1343,7 @@ xfs_unmountfs( xfs_unmountfs_wait(mp); /* wait for async bufs */ xfs_log_unmount_write(mp); xfs_log_unmount(mp); - - if ((mp->m_flags & XFS_MOUNT_NOUUID) == 0) - uuid_table_remove(&mp->m_sb.sb_uuid); + xfs_uuid_unmount(mp); #if defined(DEBUG) xfs_errortag_clearall(mp, 0); @@ -1779,29 +1844,6 @@ xfs_freesb( mp->m_sb_bp = NULL; } -/* - * See if the UUID is unique among mounted XFS filesystems. - * Mount fails if UUID is nil or a FS with the same UUID is already mounted. - */ -STATIC int -xfs_uuid_mount( - xfs_mount_t *mp) -{ - if (uuid_is_nil(&mp->m_sb.sb_uuid)) { - cmn_err(CE_WARN, - "XFS: Filesystem %s has nil UUID - can't mount", - mp->m_fsname); - return -1; - } - if (!uuid_table_insert(&mp->m_sb.sb_uuid)) { - cmn_err(CE_WARN, - "XFS: Filesystem %s has duplicate UUID - can't mount", - mp->m_fsname); - return -1; - } - return 0; -} - /* * Used to log changes to the superblock unit and width fields which could * be altered by the mount options, as well as any potential sb_features2 -- cgit v1.2.2