alistair23-linux/include/linux/quotaops.h
Jan Kara cc33412fb1 quota: Improve locking
We implement dqget() and dqput() that need neither dqonoff_mutex nor dqptr_sem.
Then move dqget() and dqput() calls so that they are not called from under
dqptr_sem. This is important because filesystem callbacks aren't called from
under dqptr_sem which used to cause *lots* of problems with lock ranking
(and with OCFS2 they became close to unsolvable).

The patch also removes two functions which were introduced solely because OCFS2
needed them to cope with the old locking scheme. As time showed, they were not
enough for OCFS2 anyway and it would be unnecessary work to adapt them to the
new locking scheme in which they aren't needed.  As a result OCFS2 needs the
following patch to compile properly with quotas.  Sorry to any bisecters which
hit this in advance.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-01-16 18:02:10 +01:00

421 lines
11 KiB
C

/*
* Definitions for diskquota-operations. When diskquota is configured these
* macros expand to the right source-code.
*
* Author: Marco van Wieringen <mvw@planets.elm.net>
*/
#ifndef _LINUX_QUOTAOPS_
#define _LINUX_QUOTAOPS_
#include <linux/smp_lock.h>
#include <linux/fs.h>
static inline struct quota_info *sb_dqopt(struct super_block *sb)
{
return &sb->s_dquot;
}
#if defined(CONFIG_QUOTA)
/*
* declaration of quota_function calls in kernel.
*/
void sync_dquots(struct super_block *sb, int type);
int dquot_initialize(struct inode *inode, int type);
int dquot_drop(struct inode *inode);
struct dquot *dqget(struct super_block *sb, unsigned int id, int type);
void dqput(struct dquot *dquot);
int dquot_scan_active(struct super_block *sb,
int (*fn)(struct dquot *dquot, unsigned long priv),
unsigned long priv);
struct dquot *dquot_alloc(struct super_block *sb, int type);
void dquot_destroy(struct dquot *dquot);
int dquot_alloc_space(struct inode *inode, qsize_t number, int prealloc);
int dquot_alloc_inode(const struct inode *inode, qsize_t number);
int dquot_free_space(struct inode *inode, qsize_t number);
int dquot_free_inode(const struct inode *inode, qsize_t number);
int dquot_transfer(struct inode *inode, struct iattr *iattr);
int dquot_commit(struct dquot *dquot);
int dquot_acquire(struct dquot *dquot);
int dquot_release(struct dquot *dquot);
int dquot_commit_info(struct super_block *sb, int type);
int dquot_mark_dquot_dirty(struct dquot *dquot);
int vfs_quota_on(struct super_block *sb, int type, int format_id,
char *path, int remount);
int vfs_quota_enable(struct inode *inode, int type, int format_id,
unsigned int flags);
int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
struct path *path);
int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
int format_id, int type);
int vfs_quota_off(struct super_block *sb, int type, int remount);
int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags);
int vfs_quota_sync(struct super_block *sb, int type);
int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);
int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);
void vfs_dq_drop(struct inode *inode);
int vfs_dq_transfer(struct inode *inode, struct iattr *iattr);
int vfs_dq_quota_on_remount(struct super_block *sb);
static inline struct mem_dqinfo *sb_dqinfo(struct super_block *sb, int type)
{
return sb_dqopt(sb)->info + type;
}
/*
* Functions for checking status of quota
*/
static inline int sb_has_quota_usage_enabled(struct super_block *sb, int type)
{
return sb_dqopt(sb)->flags &
dquot_state_flag(DQUOT_USAGE_ENABLED, type);
}
static inline int sb_has_quota_limits_enabled(struct super_block *sb, int type)
{
return sb_dqopt(sb)->flags &
dquot_state_flag(DQUOT_LIMITS_ENABLED, type);
}
static inline int sb_has_quota_suspended(struct super_block *sb, int type)
{
return sb_dqopt(sb)->flags &
dquot_state_flag(DQUOT_SUSPENDED, type);
}
static inline int sb_any_quota_suspended(struct super_block *sb)
{
return sb_has_quota_suspended(sb, USRQUOTA) ||
sb_has_quota_suspended(sb, GRPQUOTA);
}
/* Does kernel know about any quota information for given sb + type? */
static inline int sb_has_quota_loaded(struct super_block *sb, int type)
{
/* Currently if anything is on, then quota usage is on as well */
return sb_has_quota_usage_enabled(sb, type);
}
static inline int sb_any_quota_loaded(struct super_block *sb)
{
return sb_has_quota_loaded(sb, USRQUOTA) ||
sb_has_quota_loaded(sb, GRPQUOTA);
}
static inline int sb_has_quota_active(struct super_block *sb, int type)
{
return sb_has_quota_loaded(sb, type) &&
!sb_has_quota_suspended(sb, type);
}
static inline int sb_any_quota_active(struct super_block *sb)
{
return sb_has_quota_active(sb, USRQUOTA) ||
sb_has_quota_active(sb, GRPQUOTA);
}
/*
* Operations supported for diskquotas.
*/
extern struct dquot_operations dquot_operations;
extern struct quotactl_ops vfs_quotactl_ops;
#define sb_dquot_ops (&dquot_operations)
#define sb_quotactl_ops (&vfs_quotactl_ops)
/* It is better to call this function outside of any transaction as it might
* need a lot of space in journal for dquot structure allocation. */
static inline void vfs_dq_init(struct inode *inode)
{
BUG_ON(!inode->i_sb);
if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode))
inode->i_sb->dq_op->initialize(inode, -1);
}
/* The following allocation/freeing/transfer functions *must* be called inside
* a transaction (deadlocks possible otherwise) */
static inline int vfs_dq_prealloc_space_nodirty(struct inode *inode, qsize_t nr)
{
if (sb_any_quota_active(inode->i_sb)) {
/* Used space is updated in alloc_space() */
if (inode->i_sb->dq_op->alloc_space(inode, nr, 1) == NO_QUOTA)
return 1;
}
else
inode_add_bytes(inode, nr);
return 0;
}
static inline int vfs_dq_prealloc_space(struct inode *inode, qsize_t nr)
{
int ret;
if (!(ret = vfs_dq_prealloc_space_nodirty(inode, nr)))
mark_inode_dirty(inode);
return ret;
}
static inline int vfs_dq_alloc_space_nodirty(struct inode *inode, qsize_t nr)
{
if (sb_any_quota_active(inode->i_sb)) {
/* Used space is updated in alloc_space() */
if (inode->i_sb->dq_op->alloc_space(inode, nr, 0) == NO_QUOTA)
return 1;
}
else
inode_add_bytes(inode, nr);
return 0;
}
static inline int vfs_dq_alloc_space(struct inode *inode, qsize_t nr)
{
int ret;
if (!(ret = vfs_dq_alloc_space_nodirty(inode, nr)))
mark_inode_dirty(inode);
return ret;
}
static inline int vfs_dq_alloc_inode(struct inode *inode)
{
if (sb_any_quota_active(inode->i_sb)) {
vfs_dq_init(inode);
if (inode->i_sb->dq_op->alloc_inode(inode, 1) == NO_QUOTA)
return 1;
}
return 0;
}
static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
if (sb_any_quota_active(inode->i_sb))
inode->i_sb->dq_op->free_space(inode, nr);
else
inode_sub_bytes(inode, nr);
}
static inline void vfs_dq_free_space(struct inode *inode, qsize_t nr)
{
vfs_dq_free_space_nodirty(inode, nr);
mark_inode_dirty(inode);
}
static inline void vfs_dq_free_inode(struct inode *inode)
{
if (sb_any_quota_active(inode->i_sb))
inode->i_sb->dq_op->free_inode(inode, 1);
}
/* The following two functions cannot be called inside a transaction */
static inline void vfs_dq_sync(struct super_block *sb)
{
sync_dquots(sb, -1);
}
static inline int vfs_dq_off(struct super_block *sb, int remount)
{
int ret = -ENOSYS;
if (sb->s_qcop && sb->s_qcop->quota_off)
ret = sb->s_qcop->quota_off(sb, -1, remount);
return ret;
}
#else
static inline int sb_has_quota_usage_enabled(struct super_block *sb, int type)
{
return 0;
}
static inline int sb_has_quota_limits_enabled(struct super_block *sb, int type)
{
return 0;
}
static inline int sb_has_quota_suspended(struct super_block *sb, int type)
{
return 0;
}
static inline int sb_any_quota_suspended(struct super_block *sb)
{
return 0;
}
/* Does kernel know about any quota information for given sb + type? */
static inline int sb_has_quota_loaded(struct super_block *sb, int type)
{
return 0;
}
static inline int sb_any_quota_loaded(struct super_block *sb)
{
return 0;
}
static inline int sb_has_quota_active(struct super_block *sb, int type)
{
return 0;
}
static inline int sb_any_quota_active(struct super_block *sb)
{
return 0;
}
/*
* NO-OP when quota not configured.
*/
#define sb_dquot_ops (NULL)
#define sb_quotactl_ops (NULL)
static inline void vfs_dq_init(struct inode *inode)
{
}
static inline void vfs_dq_drop(struct inode *inode)
{
}
static inline int vfs_dq_alloc_inode(struct inode *inode)
{
return 0;
}
static inline void vfs_dq_free_inode(struct inode *inode)
{
}
static inline void vfs_dq_sync(struct super_block *sb)
{
}
static inline int vfs_dq_off(struct super_block *sb, int remount)
{
return 0;
}
static inline int vfs_dq_quota_on_remount(struct super_block *sb)
{
return 0;
}
static inline int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
{
return 0;
}
static inline int vfs_dq_prealloc_space_nodirty(struct inode *inode, qsize_t nr)
{
inode_add_bytes(inode, nr);
return 0;
}
static inline int vfs_dq_prealloc_space(struct inode *inode, qsize_t nr)
{
vfs_dq_prealloc_space_nodirty(inode, nr);
mark_inode_dirty(inode);
return 0;
}
static inline int vfs_dq_alloc_space_nodirty(struct inode *inode, qsize_t nr)
{
inode_add_bytes(inode, nr);
return 0;
}
static inline int vfs_dq_alloc_space(struct inode *inode, qsize_t nr)
{
vfs_dq_alloc_space_nodirty(inode, nr);
mark_inode_dirty(inode);
return 0;
}
static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
inode_sub_bytes(inode, nr);
}
static inline void vfs_dq_free_space(struct inode *inode, qsize_t nr)
{
vfs_dq_free_space_nodirty(inode, nr);
mark_inode_dirty(inode);
}
#endif /* CONFIG_QUOTA */
static inline int vfs_dq_prealloc_block_nodirty(struct inode *inode, qsize_t nr)
{
return vfs_dq_prealloc_space_nodirty(inode,
nr << inode->i_sb->s_blocksize_bits);
}
static inline int vfs_dq_prealloc_block(struct inode *inode, qsize_t nr)
{
return vfs_dq_prealloc_space(inode,
nr << inode->i_sb->s_blocksize_bits);
}
static inline int vfs_dq_alloc_block_nodirty(struct inode *inode, qsize_t nr)
{
return vfs_dq_alloc_space_nodirty(inode,
nr << inode->i_sb->s_blocksize_bits);
}
static inline int vfs_dq_alloc_block(struct inode *inode, qsize_t nr)
{
return vfs_dq_alloc_space(inode,
nr << inode->i_sb->s_blocksize_bits);
}
static inline void vfs_dq_free_block_nodirty(struct inode *inode, qsize_t nr)
{
vfs_dq_free_space_nodirty(inode, nr << inode->i_sb->s_blocksize_bits);
}
static inline void vfs_dq_free_block(struct inode *inode, qsize_t nr)
{
vfs_dq_free_space(inode, nr << inode->i_sb->s_blocksize_bits);
}
/*
* Define uppercase equivalents for compatibility with old function names
* Can go away when we think all users have been converted (15/04/2008)
*/
#define DQUOT_INIT(inode) vfs_dq_init(inode)
#define DQUOT_DROP(inode) vfs_dq_drop(inode)
#define DQUOT_PREALLOC_SPACE_NODIRTY(inode, nr) \
vfs_dq_prealloc_space_nodirty(inode, nr)
#define DQUOT_PREALLOC_SPACE(inode, nr) vfs_dq_prealloc_space(inode, nr)
#define DQUOT_ALLOC_SPACE_NODIRTY(inode, nr) \
vfs_dq_alloc_space_nodirty(inode, nr)
#define DQUOT_ALLOC_SPACE(inode, nr) vfs_dq_alloc_space(inode, nr)
#define DQUOT_PREALLOC_BLOCK_NODIRTY(inode, nr) \
vfs_dq_prealloc_block_nodirty(inode, nr)
#define DQUOT_PREALLOC_BLOCK(inode, nr) vfs_dq_prealloc_block(inode, nr)
#define DQUOT_ALLOC_BLOCK_NODIRTY(inode, nr) \
vfs_dq_alloc_block_nodirty(inode, nr)
#define DQUOT_ALLOC_BLOCK(inode, nr) vfs_dq_alloc_block(inode, nr)
#define DQUOT_ALLOC_INODE(inode) vfs_dq_alloc_inode(inode)
#define DQUOT_FREE_SPACE_NODIRTY(inode, nr) \
vfs_dq_free_space_nodirty(inode, nr)
#define DQUOT_FREE_SPACE(inode, nr) vfs_dq_free_space(inode, nr)
#define DQUOT_FREE_BLOCK_NODIRTY(inode, nr) \
vfs_dq_free_block_nodirty(inode, nr)
#define DQUOT_FREE_BLOCK(inode, nr) vfs_dq_free_block(inode, nr)
#define DQUOT_FREE_INODE(inode) vfs_dq_free_inode(inode)
#define DQUOT_TRANSFER(inode, iattr) vfs_dq_transfer(inode, iattr)
#define DQUOT_SYNC(sb) vfs_dq_sync(sb)
#define DQUOT_OFF(sb, remount) vfs_dq_off(sb, remount)
#define DQUOT_ON_REMOUNT(sb) vfs_dq_quota_on_remount(sb)
#endif /* _LINUX_QUOTAOPS_ */