Commit 8da6fd08 authored by Lukas Herbolt's avatar Lukas Herbolt Committed by Carlos Maiolino
Browse files

xfs: Use xarray to track SB UUIDs instead of plain array. 



Removing the plain array to track the UUIDs and switch
to xarray makes it more readable.

Signed-off-by: default avatarLukas Herbolt <lukas@herbolt.com>
[cem: remove unneeded return from xfs_uuid_unmount]
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarCarlos Maiolino <cem@kernel.org>
parent c1f95543

fs/xfs/xfs_mount.c

+36 −39
Original line number Diff line number Diff line
@@ -44,17 +44,36 @@ 
#include "xfs_healthmon.h"



static DEFINE_MUTEX(xfs_uuid_table_mutex);

static int xfs_uuid_table_size;

static uuid_t *xfs_uuid_table;

static DEFINE_XARRAY_ALLOC(xfs_uuid_table);



static uuid_t *

xfs_uuid_search(

	uuid_t		*new_uuid)

{

	unsigned long	index = 0;

	uuid_t		*uuid;



	xa_for_each(&xfs_uuid_table, index, uuid) {

		if (uuid_equal(uuid, new_uuid))

			return uuid;

	}

	return NULL;

}



static void

xfs_uuid_delete(

	uuid_t		*uuid,

	unsigned int	index)

{

	ASSERT(uuid_equal(xa_load(&xfs_uuid_table, index), uuid));

	xa_erase(&xfs_uuid_table, index);

}



void

xfs_uuid_table_free(void)

{

	if (xfs_uuid_table_size == 0)

		return;

	kfree(xfs_uuid_table);

	xfs_uuid_table = NULL;

	xfs_uuid_table_size = 0;

	ASSERT(xa_empty(&xfs_uuid_table));

	xa_destroy(&xfs_uuid_table);

}



/*
@@ -66,7 +85,7 @@ xfs_uuid_mount( 
	struct xfs_mount	*mp)

{

	uuid_t			*uuid = &mp->m_sb.sb_uuid;

	int			hole, i;

	int			ret;



	/* Publish UUID in struct super_block */

	super_set_uuid(mp->m_super, uuid->b, sizeof(*uuid));
@@ -80,30 +99,17 @@ xfs_uuid_mount( 
	}



	mutex_lock(&xfs_uuid_table_mutex);

	for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {

		if (uuid_is_null(&xfs_uuid_table[i])) {

			hole = i;

			continue;

		}

		if (uuid_equal(uuid, &xfs_uuid_table[i]))

			goto out_duplicate;

	}



	if (hole < 0) {

		xfs_uuid_table = krealloc(xfs_uuid_table,

			(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),

			GFP_KERNEL | __GFP_NOFAIL);

		hole = xfs_uuid_table_size++;

	}

	xfs_uuid_table[hole] = *uuid;

	if (unlikely(xfs_uuid_search(uuid))) {

		xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount",

				uuid);

		mutex_unlock(&xfs_uuid_table_mutex);

		return -EINVAL;

	}



	return 0;



 out_duplicate:

	ret = xa_alloc(&xfs_uuid_table, &mp->m_uuid_table_index, uuid,

				xa_limit_32b, GFP_KERNEL);

	mutex_unlock(&xfs_uuid_table_mutex);

	xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);

	return -EINVAL;

	return ret;

}



STATIC void
@@ -111,21 +117,12 @@ xfs_uuid_unmount( 
	struct xfs_mount	*mp)

{

	uuid_t			*uuid = &mp->m_sb.sb_uuid;

	int			i;



	if (xfs_has_nouuid(mp))

		return;



	mutex_lock(&xfs_uuid_table_mutex);

	for (i = 0; i < xfs_uuid_table_size; i++) {

		if (uuid_is_null(&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);

	xfs_uuid_delete(uuid, mp->m_uuid_table_index);

	mutex_unlock(&xfs_uuid_table_mutex);

}

fs/xfs/xfs_mount.h

+3 −0
Original line number Diff line number Diff line
@@ -346,6 +346,9 @@ typedef struct xfs_mount { 


	/* Private data referring to a health monitor object. */

	struct xfs_healthmon __rcu	*m_healthmon;



	/* Index of uuid record in the uuid xarray. */

	unsigned int		m_uuid_table_index;

} xfs_mount_t;



#define M_IGEO(mp)		(&(mp)->m_ino_geo)