forked from Minki/linux
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6: ocfs2: Remove ocfs2_dquot_initialize() and ocfs2_dquot_drop() quota: Improve locking
This commit is contained in:
Linus Torvalds
commit
cc597bc3d3
222
fs/dquot.c
222
fs/dquot.c
@ -87,14 +87,17 @@
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#define __DQUOT_PARANOIA
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/*
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* There are two quota SMP locks. dq_list_lock protects all lists with quotas
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* and quota formats and also dqstats structure containing statistics about the
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* lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures
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* and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
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* There are three quota SMP locks. dq_list_lock protects all lists with quotas
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* and quota formats, dqstats structure containing statistics about the lists
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* dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
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* also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
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* i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
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* in inode_add_bytes() and inode_sub_bytes().
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* in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
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* modifications of quota state (on quotaon and quotaoff) and readers who care
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* about latest values take it as well.
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*
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* The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock
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* The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
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* dq_list_lock > dq_state_lock
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*
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* Note that some things (eg. sb pointer, type, id) doesn't change during
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* the life of the dquot structure and so needn't to be protected by a lock
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@ -103,12 +106,7 @@
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* operation is just reading pointers from inode (or not using them at all) the
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* read lock is enough. If pointers are altered function must hold write lock
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* (these locking rules also apply for S_NOQUOTA flag in the inode - note that
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* for altering the flag i_mutex is also needed). If operation is holding
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* reference to dquot in other way (e.g. quotactl ops) it must be guarded by
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* dqonoff_mutex.
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* This locking assures that:
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* a) update/access to dquot pointers in inode is serialized
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* b) everyone is guarded against invalidate_dquots()
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* for altering the flag i_mutex is also needed).
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*
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* Each dquot has its dq_lock mutex. Locked dquots might not be referenced
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* from inodes (dquot_alloc_space() and such don't check the dq_lock).
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@ -122,10 +120,17 @@
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* Lock ordering (including related VFS locks) is the following:
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* i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
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* dqio_mutex
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* The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem >
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* dqptr_sem. But filesystem has to count with the fact that functions such as
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* dquot_alloc_space() acquire dqptr_sem and they usually have to be called
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* from inside a transaction to keep filesystem consistency after a crash. Also
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* filesystems usually want to do some IO on dquot from ->mark_dirty which is
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* called with dqptr_sem held.
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* i_mutex on quota files is special (it's below dqio_mutex)
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*/
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static DEFINE_SPINLOCK(dq_list_lock);
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static DEFINE_SPINLOCK(dq_state_lock);
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DEFINE_SPINLOCK(dq_data_lock);
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static char *quotatypes[] = INITQFNAMES;
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@ -428,7 +433,7 @@ static inline void do_destroy_dquot(struct dquot *dquot)
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* quota is disabled and pointers from inodes removed so there cannot be new
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* quota users. There can still be some users of quotas due to inodes being
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* just deleted or pruned by prune_icache() (those are not attached to any
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* list). We have to wait for such users.
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* list) or parallel quotactl call. We have to wait for such users.
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*/
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static void invalidate_dquots(struct super_block *sb, int type)
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{
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@ -600,7 +605,6 @@ static struct shrinker dqcache_shrinker = {
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/*
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* Put reference to dquot
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* NOTE: If you change this function please check whether dqput_blocks() works right...
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* MUST be called with either dqptr_sem or dqonoff_mutex held
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*/
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void dqput(struct dquot *dquot)
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{
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@ -696,37 +700,31 @@ static struct dquot *get_empty_dquot(struct super_block *sb, int type)
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return dquot;
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}
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/*
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* Check whether dquot is in memory.
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* MUST be called with either dqptr_sem or dqonoff_mutex held
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*/
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int dquot_is_cached(struct super_block *sb, unsigned int id, int type)
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{
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unsigned int hashent = hashfn(sb, id, type);
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int ret = 0;
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if (!sb_has_quota_active(sb, type))
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return 0;
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spin_lock(&dq_list_lock);
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if (find_dquot(hashent, sb, id, type) != NODQUOT)
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ret = 1;
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spin_unlock(&dq_list_lock);
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return ret;
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}
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/*
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* Get reference to dquot
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* MUST be called with either dqptr_sem or dqonoff_mutex held
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*
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* Locking is slightly tricky here. We are guarded from parallel quotaoff()
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* destroying our dquot by:
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* a) checking for quota flags under dq_list_lock and
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* b) getting a reference to dquot before we release dq_list_lock
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*/
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struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
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{
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unsigned int hashent = hashfn(sb, id, type);
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struct dquot *dquot, *empty = NODQUOT;
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struct dquot *dquot = NODQUOT, *empty = NODQUOT;
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if (!sb_has_quota_active(sb, type))
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return NODQUOT;
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we_slept:
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spin_lock(&dq_list_lock);
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spin_lock(&dq_state_lock);
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if (!sb_has_quota_active(sb, type)) {
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spin_unlock(&dq_state_lock);
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spin_unlock(&dq_list_lock);
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goto out;
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}
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spin_unlock(&dq_state_lock);
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if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) {
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if (empty == NODQUOT) {
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spin_unlock(&dq_list_lock);
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@ -735,6 +733,7 @@ we_slept:
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goto we_slept;
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}
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dquot = empty;
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empty = NODQUOT;
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dquot->dq_id = id;
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/* all dquots go on the inuse_list */
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put_inuse(dquot);
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@ -749,8 +748,6 @@ we_slept:
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dqstats.cache_hits++;
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dqstats.lookups++;
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spin_unlock(&dq_list_lock);
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if (empty)
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do_destroy_dquot(empty);
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}
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/* Wait for dq_lock - after this we know that either dquot_release() is already
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* finished or it will be canceled due to dq_count > 1 test */
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@ -758,11 +755,15 @@ we_slept:
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/* Read the dquot and instantiate it (everything done only if needed) */
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if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) {
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dqput(dquot);
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return NODQUOT;
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dquot = NODQUOT;
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goto out;
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}
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#ifdef __DQUOT_PARANOIA
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BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
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#endif
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out:
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if (empty)
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do_destroy_dquot(empty);
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return dquot;
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}
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@ -1198,63 +1199,76 @@ static int info_bdq_free(struct dquot *dquot, qsize_t space)
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}
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/*
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* Initialize quota pointers in inode
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* Transaction must be started at entry
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* We do things in a bit complicated way but by that we avoid calling
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* dqget() and thus filesystem callbacks under dqptr_sem.
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*/
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int dquot_initialize(struct inode *inode, int type)
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{
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unsigned int id = 0;
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int cnt, ret = 0;
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struct dquot *got[MAXQUOTAS] = { NODQUOT, NODQUOT };
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struct super_block *sb = inode->i_sb;
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/* First test before acquiring mutex - solves deadlocks when we
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* re-enter the quota code and are already holding the mutex */
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if (IS_NOQUOTA(inode))
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return 0;
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down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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/* First get references to structures we might need. */
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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if (type != -1 && cnt != type)
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continue;
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switch (cnt) {
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case USRQUOTA:
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id = inode->i_uid;
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break;
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case GRPQUOTA:
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id = inode->i_gid;
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break;
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}
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got[cnt] = dqget(sb, id, cnt);
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}
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down_write(&sb_dqopt(sb)->dqptr_sem);
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/* Having dqptr_sem we know NOQUOTA flags can't be altered... */
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if (IS_NOQUOTA(inode))
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goto out_err;
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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if (type != -1 && cnt != type)
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continue;
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/* Avoid races with quotaoff() */
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if (!sb_has_quota_active(sb, cnt))
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continue;
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if (inode->i_dquot[cnt] == NODQUOT) {
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switch (cnt) {
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case USRQUOTA:
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id = inode->i_uid;
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break;
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case GRPQUOTA:
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id = inode->i_gid;
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break;
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}
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inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt);
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inode->i_dquot[cnt] = got[cnt];
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got[cnt] = NODQUOT;
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}
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}
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out_err:
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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up_write(&sb_dqopt(sb)->dqptr_sem);
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/* Drop unused references */
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for (cnt = 0; cnt < MAXQUOTAS; cnt++)
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dqput(got[cnt]);
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return ret;
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}
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/*
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* Release all quotas referenced by inode
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* Transaction must be started at an entry
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*/
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int dquot_drop_locked(struct inode *inode)
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{
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int cnt;
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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if (inode->i_dquot[cnt] != NODQUOT) {
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dqput(inode->i_dquot[cnt]);
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inode->i_dquot[cnt] = NODQUOT;
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}
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}
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return 0;
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}
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int dquot_drop(struct inode *inode)
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{
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int cnt;
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struct dquot *put[MAXQUOTAS];
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down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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dquot_drop_locked(inode);
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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put[cnt] = inode->i_dquot[cnt];
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inode->i_dquot[cnt] = NODQUOT;
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}
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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for (cnt = 0; cnt < MAXQUOTAS; cnt++)
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dqput(put[cnt]);
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return 0;
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}
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@ -1470,8 +1484,9 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
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qsize_t space;
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struct dquot *transfer_from[MAXQUOTAS];
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struct dquot *transfer_to[MAXQUOTAS];
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int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid,
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chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid;
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int cnt, ret = QUOTA_OK;
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int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid,
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chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid;
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char warntype_to[MAXQUOTAS];
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char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
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@ -1479,21 +1494,11 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
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* re-enter the quota code and are already holding the mutex */
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if (IS_NOQUOTA(inode))
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return QUOTA_OK;
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/* Clear the arrays */
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/* Initialize the arrays */
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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transfer_to[cnt] = transfer_from[cnt] = NODQUOT;
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transfer_from[cnt] = NODQUOT;
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transfer_to[cnt] = NODQUOT;
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warntype_to[cnt] = QUOTA_NL_NOWARN;
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}
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down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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/* Now recheck reliably when holding dqptr_sem */
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if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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return QUOTA_OK;
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}
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/* First build the transfer_to list - here we can block on
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* reading/instantiating of dquots. We know that the transaction for
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* us was already started so we don't violate lock ranking here */
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
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switch (cnt) {
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case USRQUOTA:
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if (!chuid)
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@ -1507,6 +1512,13 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
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break;
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}
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}
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down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
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/* Now recheck reliably when holding dqptr_sem */
|
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if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
|
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goto put_all;
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}
|
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spin_lock(&dq_data_lock);
|
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space = inode_get_bytes(inode);
|
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/* Build the transfer_from list and check the limits */
|
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@ -1517,7 +1529,7 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
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if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
|
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NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
|
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warntype_to + cnt) == NO_QUOTA)
|
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goto warn_put_all;
|
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goto over_quota;
|
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}
|
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|
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/*
|
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@ -1545,28 +1557,37 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
|
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|
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inode->i_dquot[cnt] = transfer_to[cnt];
|
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}
|
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ret = QUOTA_OK;
|
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warn_put_all:
|
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spin_unlock(&dq_data_lock);
|
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
|
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|
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/* Dirtify all the dquots - this can block when journalling */
|
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
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if (transfer_from[cnt])
|
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mark_dquot_dirty(transfer_from[cnt]);
|
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if (transfer_to[cnt])
|
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if (transfer_to[cnt]) {
|
||||
mark_dquot_dirty(transfer_to[cnt]);
|
||||
/* The reference we got is transferred to the inode */
|
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transfer_to[cnt] = NODQUOT;
|
||||
}
|
||||
}
|
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warn_put_all:
|
||||
flush_warnings(transfer_to, warntype_to);
|
||||
flush_warnings(transfer_from, warntype_from_inodes);
|
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flush_warnings(transfer_from, warntype_from_space);
|
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|
||||
put_all:
|
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for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
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if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT)
|
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dqput(transfer_from[cnt]);
|
||||
if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT)
|
||||
dqput(transfer_to[cnt]);
|
||||
dqput(transfer_from[cnt]);
|
||||
dqput(transfer_to[cnt]);
|
||||
}
|
||||
up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
|
||||
return ret;
|
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over_quota:
|
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spin_unlock(&dq_data_lock);
|
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up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
|
||||
/* Clear dquot pointers we don't want to dqput() */
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++)
|
||||
transfer_from[cnt] = NODQUOT;
|
||||
ret = NO_QUOTA;
|
||||
goto warn_put_all;
|
||||
}
|
||||
|
||||
/* Wrapper for transferring ownership of an inode */
|
||||
@ -1651,19 +1672,24 @@ int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags)
|
||||
continue;
|
||||
|
||||
if (flags & DQUOT_SUSPENDED) {
|
||||
spin_lock(&dq_state_lock);
|
||||
dqopt->flags |=
|
||||
dquot_state_flag(DQUOT_SUSPENDED, cnt);
|
||||
spin_unlock(&dq_state_lock);
|
||||
} else {
|
||||
spin_lock(&dq_state_lock);
|
||||
dqopt->flags &= ~dquot_state_flag(flags, cnt);
|
||||
/* Turning off suspended quotas? */
|
||||
if (!sb_has_quota_loaded(sb, cnt) &&
|
||||
sb_has_quota_suspended(sb, cnt)) {
|
||||
dqopt->flags &= ~dquot_state_flag(
|
||||
DQUOT_SUSPENDED, cnt);
|
||||
spin_unlock(&dq_state_lock);
|
||||
iput(dqopt->files[cnt]);
|
||||
dqopt->files[cnt] = NULL;
|
||||
continue;
|
||||
}
|
||||
spin_unlock(&dq_state_lock);
|
||||
}
|
||||
|
||||
/* We still have to keep quota loaded? */
|
||||
@ -1830,7 +1856,9 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
|
||||
}
|
||||
mutex_unlock(&dqopt->dqio_mutex);
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
spin_lock(&dq_state_lock);
|
||||
dqopt->flags |= dquot_state_flag(flags, type);
|
||||
spin_unlock(&dq_state_lock);
|
||||
|
||||
add_dquot_ref(sb, type);
|
||||
mutex_unlock(&dqopt->dqonoff_mutex);
|
||||
@ -1872,9 +1900,11 @@ static int vfs_quota_on_remount(struct super_block *sb, int type)
|
||||
}
|
||||
inode = dqopt->files[type];
|
||||
dqopt->files[type] = NULL;
|
||||
spin_lock(&dq_state_lock);
|
||||
flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
|
||||
DQUOT_LIMITS_ENABLED, type);
|
||||
dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type);
|
||||
spin_unlock(&dq_state_lock);
|
||||
mutex_unlock(&dqopt->dqonoff_mutex);
|
||||
|
||||
flags = dquot_generic_flag(flags, type);
|
||||
@ -1952,7 +1982,9 @@ int vfs_quota_enable(struct inode *inode, int type, int format_id,
|
||||
ret = -EBUSY;
|
||||
goto out_lock;
|
||||
}
|
||||
spin_lock(&dq_state_lock);
|
||||
sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
|
||||
spin_unlock(&dq_state_lock);
|
||||
out_lock:
|
||||
mutex_unlock(&dqopt->dqonoff_mutex);
|
||||
return ret;
|
||||
@ -2039,14 +2071,12 @@ int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d
|
||||
{
|
||||
struct dquot *dquot;
|
||||
|
||||
mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
|
||||
if (!(dquot = dqget(sb, id, type))) {
|
||||
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
|
||||
dquot = dqget(sb, id, type);
|
||||
if (dquot == NODQUOT)
|
||||
return -ESRCH;
|
||||
}
|
||||
do_get_dqblk(dquot, di);
|
||||
dqput(dquot);
|
||||
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -2130,7 +2160,6 @@ int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d
|
||||
struct dquot *dquot;
|
||||
int rc;
|
||||
|
||||
mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
|
||||
dquot = dqget(sb, id, type);
|
||||
if (!dquot) {
|
||||
rc = -ESRCH;
|
||||
@ -2139,7 +2168,6 @@ int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d
|
||||
rc = do_set_dqblk(dquot, di);
|
||||
dqput(dquot);
|
||||
out:
|
||||
mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
|
||||
return rc;
|
||||
}
|
||||
|
||||
@ -2370,11 +2398,9 @@ EXPORT_SYMBOL(dquot_release);
|
||||
EXPORT_SYMBOL(dquot_mark_dquot_dirty);
|
||||
EXPORT_SYMBOL(dquot_initialize);
|
||||
EXPORT_SYMBOL(dquot_drop);
|
||||
EXPORT_SYMBOL(dquot_drop_locked);
|
||||
EXPORT_SYMBOL(vfs_dq_drop);
|
||||
EXPORT_SYMBOL(dqget);
|
||||
EXPORT_SYMBOL(dqput);
|
||||
EXPORT_SYMBOL(dquot_is_cached);
|
||||
EXPORT_SYMBOL(dquot_alloc_space);
|
||||
EXPORT_SYMBOL(dquot_alloc_inode);
|
||||
EXPORT_SYMBOL(dquot_free_space);
|
||||
|
||||
@ -810,171 +810,6 @@ out:
|
||||
return status;
|
||||
}
|
||||
|
||||
/* This is difficult. We have to lock quota inode and start transaction
|
||||
* in this function but we don't want to take the penalty of exlusive
|
||||
* quota file lock when we are just going to use cached structures. So
|
||||
* we just take read lock check whether we have dquot cached and if so,
|
||||
* we don't have to take the write lock... */
|
||||
static int ocfs2_dquot_initialize(struct inode *inode, int type)
|
||||
{
|
||||
handle_t *handle = NULL;
|
||||
int status = 0;
|
||||
struct super_block *sb = inode->i_sb;
|
||||
struct ocfs2_mem_dqinfo *oinfo;
|
||||
int exclusive = 0;
|
||||
int cnt;
|
||||
qid_t id;
|
||||
|
||||
mlog_entry_void();
|
||||
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
||||
if (type != -1 && cnt != type)
|
||||
continue;
|
||||
if (!sb_has_quota_active(sb, cnt))
|
||||
continue;
|
||||
oinfo = sb_dqinfo(sb, cnt)->dqi_priv;
|
||||
status = ocfs2_lock_global_qf(oinfo, 0);
|
||||
if (status < 0)
|
||||
goto out;
|
||||
/* This is just a performance optimization not a reliable test.
|
||||
* Since we hold an inode lock, noone can actually release
|
||||
* the structure until we are finished with initialization. */
|
||||
if (inode->i_dquot[cnt] != NODQUOT) {
|
||||
ocfs2_unlock_global_qf(oinfo, 0);
|
||||
continue;
|
||||
}
|
||||
/* When we have inode lock, we know that no dquot_release() can
|
||||
* run and thus we can safely check whether we need to
|
||||
* read+modify global file to get quota information or whether
|
||||
* our node already has it. */
|
||||
if (cnt == USRQUOTA)
|
||||
id = inode->i_uid;
|
||||
else if (cnt == GRPQUOTA)
|
||||
id = inode->i_gid;
|
||||
else
|
||||
BUG();
|
||||
/* Obtain exclusion from quota off... */
|
||||
down_write(&sb_dqopt(sb)->dqptr_sem);
|
||||
exclusive = !dquot_is_cached(sb, id, cnt);
|
||||
up_write(&sb_dqopt(sb)->dqptr_sem);
|
||||
if (exclusive) {
|
||||
status = ocfs2_lock_global_qf(oinfo, 1);
|
||||
if (status < 0) {
|
||||
exclusive = 0;
|
||||
mlog_errno(status);
|
||||
goto out_ilock;
|
||||
}
|
||||
handle = ocfs2_start_trans(OCFS2_SB(sb),
|
||||
ocfs2_calc_qinit_credits(sb, cnt));
|
||||
if (IS_ERR(handle)) {
|
||||
status = PTR_ERR(handle);
|
||||
mlog_errno(status);
|
||||
goto out_ilock;
|
||||
}
|
||||
}
|
||||
dquot_initialize(inode, cnt);
|
||||
if (exclusive) {
|
||||
ocfs2_commit_trans(OCFS2_SB(sb), handle);
|
||||
ocfs2_unlock_global_qf(oinfo, 1);
|
||||
}
|
||||
ocfs2_unlock_global_qf(oinfo, 0);
|
||||
}
|
||||
mlog_exit(0);
|
||||
return 0;
|
||||
out_ilock:
|
||||
if (exclusive)
|
||||
ocfs2_unlock_global_qf(oinfo, 1);
|
||||
ocfs2_unlock_global_qf(oinfo, 0);
|
||||
out:
|
||||
mlog_exit(status);
|
||||
return status;
|
||||
}
|
||||
|
||||
static int ocfs2_dquot_drop_slow(struct inode *inode)
|
||||
{
|
||||
int status = 0;
|
||||
int cnt;
|
||||
int got_lock[MAXQUOTAS] = {0, 0};
|
||||
handle_t *handle;
|
||||
struct super_block *sb = inode->i_sb;
|
||||
struct ocfs2_mem_dqinfo *oinfo;
|
||||
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
||||
if (!sb_has_quota_active(sb, cnt))
|
||||
continue;
|
||||
oinfo = sb_dqinfo(sb, cnt)->dqi_priv;
|
||||
status = ocfs2_lock_global_qf(oinfo, 1);
|
||||
if (status < 0)
|
||||
goto out;
|
||||
got_lock[cnt] = 1;
|
||||
}
|
||||
handle = ocfs2_start_trans(OCFS2_SB(sb),
|
||||
ocfs2_calc_qinit_credits(sb, USRQUOTA) +
|
||||
ocfs2_calc_qinit_credits(sb, GRPQUOTA));
|
||||
if (IS_ERR(handle)) {
|
||||
status = PTR_ERR(handle);
|
||||
mlog_errno(status);
|
||||
goto out;
|
||||
}
|
||||
dquot_drop(inode);
|
||||
ocfs2_commit_trans(OCFS2_SB(sb), handle);
|
||||
out:
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++)
|
||||
if (got_lock[cnt]) {
|
||||
oinfo = sb_dqinfo(sb, cnt)->dqi_priv;
|
||||
ocfs2_unlock_global_qf(oinfo, 1);
|
||||
}
|
||||
return status;
|
||||
}
|
||||
|
||||
/* See the comment before ocfs2_dquot_initialize. */
|
||||
static int ocfs2_dquot_drop(struct inode *inode)
|
||||
{
|
||||
int status = 0;
|
||||
struct super_block *sb = inode->i_sb;
|
||||
struct ocfs2_mem_dqinfo *oinfo;
|
||||
int exclusive = 0;
|
||||
int cnt;
|
||||
int got_lock[MAXQUOTAS] = {0, 0};
|
||||
|
||||
mlog_entry_void();
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
||||
if (!sb_has_quota_active(sb, cnt))
|
||||
continue;
|
||||
oinfo = sb_dqinfo(sb, cnt)->dqi_priv;
|
||||
status = ocfs2_lock_global_qf(oinfo, 0);
|
||||
if (status < 0)
|
||||
goto out;
|
||||
got_lock[cnt] = 1;
|
||||
}
|
||||
/* Lock against anyone releasing references so that when when we check
|
||||
* we know we are not going to be last ones to release dquot */
|
||||
down_write(&sb_dqopt(sb)->dqptr_sem);
|
||||
/* Urgh, this is a terrible hack :( */
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
|
||||
if (inode->i_dquot[cnt] != NODQUOT &&
|
||||
atomic_read(&inode->i_dquot[cnt]->dq_count) > 1) {
|
||||
exclusive = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!exclusive)
|
||||
dquot_drop_locked(inode);
|
||||
up_write(&sb_dqopt(sb)->dqptr_sem);
|
||||
out:
|
||||
for (cnt = 0; cnt < MAXQUOTAS; cnt++)
|
||||
if (got_lock[cnt]) {
|
||||
oinfo = sb_dqinfo(sb, cnt)->dqi_priv;
|
||||
ocfs2_unlock_global_qf(oinfo, 0);
|
||||
}
|
||||
/* In case we bailed out because we had to do expensive locking
|
||||
* do it now... */
|
||||
if (exclusive)
|
||||
status = ocfs2_dquot_drop_slow(inode);
|
||||
mlog_exit(status);
|
||||
return status;
|
||||
}
|
||||
|
||||
static struct dquot *ocfs2_alloc_dquot(struct super_block *sb, int type)
|
||||
{
|
||||
struct ocfs2_dquot *dquot =
|
||||
@ -991,8 +826,8 @@ static void ocfs2_destroy_dquot(struct dquot *dquot)
|
||||
}
|
||||
|
||||
struct dquot_operations ocfs2_quota_operations = {
|
||||
.initialize = ocfs2_dquot_initialize,
|
||||
.drop = ocfs2_dquot_drop,
|
||||
.initialize = dquot_initialize,
|
||||
.drop = dquot_drop,
|
||||
.alloc_space = dquot_alloc_space,
|
||||
.alloc_inode = dquot_alloc_inode,
|
||||
.free_space = dquot_free_space,
|
||||
|
||||
@ -24,10 +24,8 @@ void sync_dquots(struct super_block *sb, int type);
|
||||
|
||||
int dquot_initialize(struct inode *inode, int type);
|
||||
int dquot_drop(struct inode *inode);
|
||||
int dquot_drop_locked(struct inode *inode);
|
||||
struct dquot *dqget(struct super_block *sb, unsigned int id, int type);
|
||||
void dqput(struct dquot *dquot);
|
||||
int dquot_is_cached(struct super_block *sb, unsigned int id, int type);
|
||||
int dquot_scan_active(struct super_block *sb,
|
||||
int (*fn)(struct dquot *dquot, unsigned long priv),
|
||||
unsigned long priv);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user