Commit 27174203 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Christoph Hellwig
Browse files

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: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarFelix Blyakher <felixb@sgi.com>
parent 1a5902c5

fs/xfs/support/uuid.c

+0 −71
Original line number Diff line number Diff line
@@ -17,10 +17,6 @@ 
 */

#include <xfs.h>



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);

}

fs/xfs/support/uuid.h

+0 −4
Original line number Diff line number Diff line
@@ -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__ */

fs/xfs/xfs_mount.c

+83 −41
Original line number Diff line number Diff line
@@ -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);

	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

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