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-rw-r--r--fs/quota/dquot.c2617
1 files changed, 2617 insertions, 0 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
new file mode 100644
index 000000000000..2ca967a5ef77
--- /dev/null
+++ b/fs/quota/dquot.c
@@ -0,0 +1,2617 @@
+/*
+ * Implementation of the diskquota system for the LINUX operating system. QUOTA
+ * is implemented using the BSD system call interface as the means of
+ * communication with the user level. This file contains the generic routines
+ * called by the different filesystems on allocation of an inode or block.
+ * These routines take care of the administration needed to have a consistent
+ * diskquota tracking system. The ideas of both user and group quotas are based
+ * on the Melbourne quota system as used on BSD derived systems. The internal
+ * implementation is based on one of the several variants of the LINUX
+ * inode-subsystem with added complexity of the diskquota system.
+ *
+ * Author: Marco van Wieringen <mvw@planets.elm.net>
+ *
+ * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
+ *
+ * Revised list management to avoid races
+ * -- Bill Hawes, <whawes@star.net>, 9/98
+ *
+ * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
+ * As the consequence the locking was moved from dquot_decr_...(),
+ * dquot_incr_...() to calling functions.
+ * invalidate_dquots() now writes modified dquots.
+ * Serialized quota_off() and quota_on() for mount point.
+ * Fixed a few bugs in grow_dquots().
+ * Fixed deadlock in write_dquot() - we no longer account quotas on
+ * quota files
+ * remove_dquot_ref() moved to inode.c - it now traverses through inodes
+ * add_dquot_ref() restarts after blocking
+ * Added check for bogus uid and fixed check for group in quotactl.
+ * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
+ *
+ * Used struct list_head instead of own list struct
+ * Invalidation of referenced dquots is no longer possible
+ * Improved free_dquots list management
+ * Quota and i_blocks are now updated in one place to avoid races
+ * Warnings are now delayed so we won't block in critical section
+ * Write updated not to require dquot lock
+ * Jan Kara, <jack@suse.cz>, 9/2000
+ *
+ * Added dynamic quota structure allocation
+ * Jan Kara <jack@suse.cz> 12/2000
+ *
+ * Rewritten quota interface. Implemented new quota format and
+ * formats registering.
+ * Jan Kara, <jack@suse.cz>, 2001,2002
+ *
+ * New SMP locking.
+ * Jan Kara, <jack@suse.cz>, 10/2002
+ *
+ * Added journalled quota support, fix lock inversion problems
+ * Jan Kara, <jack@suse.cz>, 2003,2004
+ *
+ * (C) Copyright 1994 - 1997 Marco van Wieringen
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/mm.h>
+#include <linux/time.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/tty.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/security.h>
+#include <linux/kmod.h>
+#include <linux/namei.h>
+#include <linux/buffer_head.h>
+#include <linux/capability.h>
+#include <linux/quotaops.h>
+#include <linux/writeback.h> /* for inode_lock, oddly enough.. */
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+#include <net/netlink.h>
+#include <net/genetlink.h>
+#endif
+
+#include <asm/uaccess.h>
+
+#define __DQUOT_PARANOIA
+
+/*
+ * There are three quota SMP locks. dq_list_lock protects all lists with quotas
+ * and quota formats, dqstats structure containing statistics about the lists
+ * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
+ * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
+ * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
+ * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
+ * modifications of quota state (on quotaon and quotaoff) and readers who care
+ * about latest values take it as well.
+ *
+ * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
+ * dq_list_lock > dq_state_lock
+ *
+ * Note that some things (eg. sb pointer, type, id) doesn't change during
+ * the life of the dquot structure and so needn't to be protected by a lock
+ *
+ * Any operation working on dquots via inode pointers must hold dqptr_sem. If
+ * operation is just reading pointers from inode (or not using them at all) the
+ * read lock is enough. If pointers are altered function must hold write lock
+ * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
+ * for altering the flag i_mutex is also needed).
+ *
+ * Each dquot has its dq_lock mutex. Locked dquots might not be referenced
+ * from inodes (dquot_alloc_space() and such don't check the dq_lock).
+ * Currently dquot is locked only when it is being read to memory (or space for
+ * it is being allocated) on the first dqget() and when it is being released on
+ * the last dqput(). The allocation and release oparations are serialized by
+ * the dq_lock and by checking the use count in dquot_release(). Write
+ * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
+ * spinlock to internal buffers before writing.
+ *
+ * Lock ordering (including related VFS locks) is the following:
+ * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
+ * dqio_mutex
+ * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem >
+ * dqptr_sem. But filesystem has to count with the fact that functions such as
+ * dquot_alloc_space() acquire dqptr_sem and they usually have to be called
+ * from inside a transaction to keep filesystem consistency after a crash. Also
+ * filesystems usually want to do some IO on dquot from ->mark_dirty which is
+ * called with dqptr_sem held.
+ * i_mutex on quota files is special (it's below dqio_mutex)
+ */
+
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
+__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
+EXPORT_SYMBOL(dq_data_lock);
+
+static char *quotatypes[] = INITQFNAMES;
+static struct quota_format_type *quota_formats; /* List of registered formats */
+static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
+
+/* SLAB cache for dquot structures */
+static struct kmem_cache *dquot_cachep;
+
+int register_quota_format(struct quota_format_type *fmt)
+{
+ spin_lock(&dq_list_lock);
+ fmt->qf_next = quota_formats;
+ quota_formats = fmt;
+ spin_unlock(&dq_list_lock);
+ return 0;
+}
+EXPORT_SYMBOL(register_quota_format);
+
+void unregister_quota_format(struct quota_format_type *fmt)
+{
+ struct quota_format_type **actqf;
+
+ spin_lock(&dq_list_lock);
+ for (actqf = &quota_formats; *actqf && *actqf != fmt;
+ actqf = &(*actqf)->qf_next)
+ ;
+ if (*actqf)
+ *actqf = (*actqf)->qf_next;
+ spin_unlock(&dq_list_lock);
+}
+EXPORT_SYMBOL(unregister_quota_format);
+
+static struct quota_format_type *find_quota_format(int id)
+{
+ struct quota_format_type *actqf;
+
+ spin_lock(&dq_list_lock);
+ for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
+ actqf = actqf->qf_next)
+ ;
+ if (!actqf || !try_module_get(actqf->qf_owner)) {
+ int qm;
+
+ spin_unlock(&dq_list_lock);
+
+ for (qm = 0; module_names[qm].qm_fmt_id &&
+ module_names[qm].qm_fmt_id != id; qm++)
+ ;
+ if (!module_names[qm].qm_fmt_id ||
+ request_module(module_names[qm].qm_mod_name))
+ return NULL;
+
+ spin_lock(&dq_list_lock);
+ for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
+ actqf = actqf->qf_next)
+ ;
+ if (actqf && !try_module_get(actqf->qf_owner))
+ actqf = NULL;
+ }
+ spin_unlock(&dq_list_lock);
+ return actqf;
+}
+
+static void put_quota_format(struct quota_format_type *fmt)
+{
+ module_put(fmt->qf_owner);
+}
+
+/*
+ * Dquot List Management:
+ * The quota code uses three lists for dquot management: the inuse_list,
+ * free_dquots, and dquot_hash[] array. A single dquot structure may be
+ * on all three lists, depending on its current state.
+ *
+ * All dquots are placed to the end of inuse_list when first created, and this
+ * list is used for invalidate operation, which must look at every dquot.
+ *
+ * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
+ * and this list is searched whenever we need an available dquot. Dquots are
+ * removed from the list as soon as they are used again, and
+ * dqstats.free_dquots gives the number of dquots on the list. When
+ * dquot is invalidated it's completely released from memory.
+ *
+ * Dquots with a specific identity (device, type and id) are placed on
+ * one of the dquot_hash[] hash chains. The provides an efficient search
+ * mechanism to locate a specific dquot.
+ */
+
+static LIST_HEAD(inuse_list);
+static LIST_HEAD(free_dquots);
+static unsigned int dq_hash_bits, dq_hash_mask;
+static struct hlist_head *dquot_hash;
+
+struct dqstats dqstats;
+EXPORT_SYMBOL(dqstats);
+
+static inline unsigned int
+hashfn(const struct super_block *sb, unsigned int id, int type)
+{
+ unsigned long tmp;
+
+ tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
+ return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
+}
+
+/*
+ * Following list functions expect dq_list_lock to be held
+ */
+static inline void insert_dquot_hash(struct dquot *dquot)
+{
+ struct hlist_head *head;
+ head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
+ hlist_add_head(&dquot->dq_hash, head);
+}
+
+static inline void remove_dquot_hash(struct dquot *dquot)
+{
+ hlist_del_init(&dquot->dq_hash);
+}
+
+static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
+ unsigned int id, int type)
+{
+ struct hlist_node *node;
+ struct dquot *dquot;
+
+ hlist_for_each (node, dquot_hash+hashent) {
+ dquot = hlist_entry(node, struct dquot, dq_hash);
+ if (dquot->dq_sb == sb && dquot->dq_id == id &&
+ dquot->dq_type == type)
+ return dquot;
+ }
+ return NULL;
+}
+
+/* Add a dquot to the tail of the free list */
+static inline void put_dquot_last(struct dquot *dquot)
+{
+ list_add_tail(&dquot->dq_free, &free_dquots);
+ dqstats.free_dquots++;
+}
+
+static inline void remove_free_dquot(struct dquot *dquot)
+{
+ if (list_empty(&dquot->dq_free))
+ return;
+ list_del_init(&dquot->dq_free);
+ dqstats.free_dquots--;
+}
+
+static inline void put_inuse(struct dquot *dquot)
+{
+ /* We add to the back of inuse list so we don't have to restart
+ * when traversing this list and we block */
+ list_add_tail(&dquot->dq_inuse, &inuse_list);
+ dqstats.allocated_dquots++;
+}
+
+static inline void remove_inuse(struct dquot *dquot)
+{
+ dqstats.allocated_dquots--;
+ list_del(&dquot->dq_inuse);
+}
+/*
+ * End of list functions needing dq_list_lock
+ */
+
+static void wait_on_dquot(struct dquot *dquot)
+{
+ mutex_lock(&dquot->dq_lock);
+ mutex_unlock(&dquot->dq_lock);
+}
+
+static inline int dquot_dirty(struct dquot *dquot)
+{
+ return test_bit(DQ_MOD_B, &dquot->dq_flags);
+}
+
+static inline int mark_dquot_dirty(struct dquot *dquot)
+{
+ return dquot->dq_sb->dq_op->mark_dirty(dquot);
+}
+
+int dquot_mark_dquot_dirty(struct dquot *dquot)
+{
+ spin_lock(&dq_list_lock);
+ if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
+ list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
+ info[dquot->dq_type].dqi_dirty_list);
+ spin_unlock(&dq_list_lock);
+ return 0;
+}
+EXPORT_SYMBOL(dquot_mark_dquot_dirty);
+
+/* This function needs dq_list_lock */
+static inline int clear_dquot_dirty(struct dquot *dquot)
+{
+ if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
+ return 0;
+ list_del_init(&dquot->dq_dirty);
+ return 1;
+}
+
+void mark_info_dirty(struct super_block *sb, int type)
+{
+ set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
+}
+EXPORT_SYMBOL(mark_info_dirty);
+
+/*
+ * Read dquot from disk and alloc space for it
+ */
+
+int dquot_acquire(struct dquot *dquot)
+{
+ int ret = 0, ret2 = 0;
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+ mutex_lock(&dquot->dq_lock);
+ mutex_lock(&dqopt->dqio_mutex);
+ if (!test_bit(DQ_READ_B, &dquot->dq_flags))
+ ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
+ if (ret < 0)
+ goto out_iolock;
+ set_bit(DQ_READ_B, &dquot->dq_flags);
+ /* Instantiate dquot if needed */
+ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
+ ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
+ /* Write the info if needed */
+ if (info_dirty(&dqopt->info[dquot->dq_type])) {
+ ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
+ dquot->dq_sb, dquot->dq_type);
+ }
+ if (ret < 0)
+ goto out_iolock;
+ if (ret2 < 0) {
+ ret = ret2;
+ goto out_iolock;
+ }
+ }
+ set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
+out_iolock:
+ mutex_unlock(&dqopt->dqio_mutex);
+ mutex_unlock(&dquot->dq_lock);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_acquire);
+
+/*
+ * Write dquot to disk
+ */
+int dquot_commit(struct dquot *dquot)
+{
+ int ret = 0, ret2 = 0;
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+ mutex_lock(&dqopt->dqio_mutex);
+ spin_lock(&dq_list_lock);
+ if (!clear_dquot_dirty(dquot)) {
+ spin_unlock(&dq_list_lock);
+ goto out_sem;
+ }
+ spin_unlock(&dq_list_lock);
+ /* Inactive dquot can be only if there was error during read/init
+ * => we have better not writing it */
+ if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+ ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
+ if (info_dirty(&dqopt->info[dquot->dq_type])) {
+ ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
+ dquot->dq_sb, dquot->dq_type);
+ }
+ if (ret >= 0)
+ ret = ret2;
+ }
+out_sem:
+ mutex_unlock(&dqopt->dqio_mutex);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_commit);
+
+/*
+ * Release dquot
+ */
+int dquot_release(struct dquot *dquot)
+{
+ int ret = 0, ret2 = 0;
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+ mutex_lock(&dquot->dq_lock);
+ /* Check whether we are not racing with some other dqget() */
+ if (atomic_read(&dquot->dq_count) > 1)
+ goto out_dqlock;
+ mutex_lock(&dqopt->dqio_mutex);
+ if (dqopt->ops[dquot->dq_type]->release_dqblk) {
+ ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
+ /* Write the info */
+ if (info_dirty(&dqopt->info[dquot->dq_type])) {
+ ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
+ dquot->dq_sb, dquot->dq_type);
+ }
+ if (ret >= 0)
+ ret = ret2;
+ }
+ clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
+ mutex_unlock(&dqopt->dqio_mutex);
+out_dqlock:
+ mutex_unlock(&dquot->dq_lock);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_release);
+
+void dquot_destroy(struct dquot *dquot)
+{
+ kmem_cache_free(dquot_cachep, dquot);
+}
+EXPORT_SYMBOL(dquot_destroy);
+
+static inline void do_destroy_dquot(struct dquot *dquot)
+{
+ dquot->dq_sb->dq_op->destroy_dquot(dquot);
+}
+
+/* Invalidate all dquots on the list. Note that this function is called after
+ * quota is disabled and pointers from inodes removed so there cannot be new
+ * quota users. There can still be some users of quotas due to inodes being
+ * just deleted or pruned by prune_icache() (those are not attached to any
+ * list) or parallel quotactl call. We have to wait for such users.
+ */
+static void invalidate_dquots(struct super_block *sb, int type)
+{
+ struct dquot *dquot, *tmp;
+
+restart:
+ spin_lock(&dq_list_lock);
+ list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
+ if (dquot->dq_sb != sb)
+ continue;
+ if (dquot->dq_type != type)
+ continue;
+ /* Wait for dquot users */
+ if (atomic_read(&dquot->dq_count)) {
+ DEFINE_WAIT(wait);
+
+ atomic_inc(&dquot->dq_count);
+ prepare_to_wait(&dquot->dq_wait_unused, &wait,
+ TASK_UNINTERRUPTIBLE);
+ spin_unlock(&dq_list_lock);
+ /* Once dqput() wakes us up, we know it's time to free
+ * the dquot.
+ * IMPORTANT: we rely on the fact that there is always
+ * at most one process waiting for dquot to free.
+ * Otherwise dq_count would be > 1 and we would never
+ * wake up.
+ */
+ if (atomic_read(&dquot->dq_count) > 1)
+ schedule();
+ finish_wait(&dquot->dq_wait_unused, &wait);
+ dqput(dquot);
+ /* At this moment dquot() need not exist (it could be
+ * reclaimed by prune_dqcache(). Hence we must
+ * restart. */
+ goto restart;
+ }
+ /*
+ * Quota now has no users and it has been written on last
+ * dqput()
+ */
+ remove_dquot_hash(dquot);
+ remove_free_dquot(dquot);
+ remove_inuse(dquot);
+ do_destroy_dquot(dquot);
+ }
+ spin_unlock(&dq_list_lock);
+}
+
+/* Call callback for every active dquot on given filesystem */
+int dquot_scan_active(struct super_block *sb,
+ int (*fn)(struct dquot *dquot, unsigned long priv),
+ unsigned long priv)
+{
+ struct dquot *dquot, *old_dquot = NULL;
+ int ret = 0;
+
+ mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+ spin_lock(&dq_list_lock);
+ list_for_each_entry(dquot, &inuse_list, dq_inuse) {
+ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
+ continue;
+ if (dquot->dq_sb != sb)
+ continue;
+ /* Now we have active dquot so we can just increase use count */
+ atomic_inc(&dquot->dq_count);
+ dqstats.lookups++;
+ spin_unlock(&dq_list_lock);
+ dqput(old_dquot);
+ old_dquot = dquot;
+ ret = fn(dquot, priv);
+ if (ret < 0)
+ goto out;
+ spin_lock(&dq_list_lock);
+ /* We are safe to continue now because our dquot could not
+ * be moved out of the inuse list while we hold the reference */
+ }
+ spin_unlock(&dq_list_lock);
+out:
+ dqput(old_dquot);
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_scan_active);
+
+int vfs_quota_sync(struct super_block *sb, int type)
+{
+ struct list_head *dirty;
+ struct dquot *dquot;
+ struct quota_info *dqopt = sb_dqopt(sb);
+ int cnt;
+
+ mutex_lock(&dqopt->dqonoff_mutex);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (type != -1 && cnt != type)
+ continue;
+ if (!sb_has_quota_active(sb, cnt))
+ continue;
+ spin_lock(&dq_list_lock);
+ dirty = &dqopt->info[cnt].dqi_dirty_list;
+ while (!list_empty(dirty)) {
+ dquot = list_first_entry(dirty, struct dquot,
+ dq_dirty);
+ /* Dirty and inactive can be only bad dquot... */
+ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+ clear_dquot_dirty(dquot);
+ continue;
+ }
+ /* Now we have active dquot from which someone is
+ * holding reference so we can safely just increase
+ * use count */
+ atomic_inc(&dquot->dq_count);
+ dqstats.lookups++;
+ spin_unlock(&dq_list_lock);
+ sb->dq_op->write_dquot(dquot);
+ dqput(dquot);
+ spin_lock(&dq_list_lock);
+ }
+ spin_unlock(&dq_list_lock);
+ }
+
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
+ && info_dirty(&dqopt->info[cnt]))
+ sb->dq_op->write_info(sb, cnt);
+ spin_lock(&dq_list_lock);
+ dqstats.syncs++;
+ spin_unlock(&dq_list_lock);
+ mutex_unlock(&dqopt->dqonoff_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL(vfs_quota_sync);
+
+/* Free unused dquots from cache */
+static void prune_dqcache(int count)
+{
+ struct list_head *head;
+ struct dquot *dquot;
+
+ head = free_dquots.prev;
+ while (head != &free_dquots && count) {
+ dquot = list_entry(head, struct dquot, dq_free);
+ remove_dquot_hash(dquot);
+ remove_free_dquot(dquot);
+ remove_inuse(dquot);
+ do_destroy_dquot(dquot);
+ count--;
+ head = free_dquots.prev;
+ }
+}
+
+/*
+ * This is called from kswapd when we think we need some
+ * more memory
+ */
+
+static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
+{
+ if (nr) {
+ spin_lock(&dq_list_lock);
+ prune_dqcache(nr);
+ spin_unlock(&dq_list_lock);
+ }
+ return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
+}
+
+static struct shrinker dqcache_shrinker = {
+ .shrink = shrink_dqcache_memory,
+ .seeks = DEFAULT_SEEKS,
+};
+
+/*
+ * Put reference to dquot
+ * NOTE: If you change this function please check whether dqput_blocks() works right...
+ */
+void dqput(struct dquot *dquot)
+{
+ int ret;
+
+ if (!dquot)
+ return;
+#ifdef __DQUOT_PARANOIA
+ if (!atomic_read(&dquot->dq_count)) {
+ printk("VFS: dqput: trying to free free dquot\n");
+ printk("VFS: device %s, dquot of %s %d\n",
+ dquot->dq_sb->s_id,
+ quotatypes[dquot->dq_type],
+ dquot->dq_id);
+ BUG();
+ }
+#endif
+
+ spin_lock(&dq_list_lock);
+ dqstats.drops++;
+ spin_unlock(&dq_list_lock);
+we_slept:
+ spin_lock(&dq_list_lock);
+ if (atomic_read(&dquot->dq_count) > 1) {
+ /* We have more than one user... nothing to do */
+ atomic_dec(&dquot->dq_count);
+ /* Releasing dquot during quotaoff phase? */
+ if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) &&
+ atomic_read(&dquot->dq_count) == 1)
+ wake_up(&dquot->dq_wait_unused);
+ spin_unlock(&dq_list_lock);
+ return;
+ }
+ /* Need to release dquot? */
+ if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
+ spin_unlock(&dq_list_lock);
+ /* Commit dquot before releasing */
+ ret = dquot->dq_sb->dq_op->write_dquot(dquot);
+ if (ret < 0) {
+ printk(KERN_ERR "VFS: cannot write quota structure on "
+ "device %s (error %d). Quota may get out of "
+ "sync!\n", dquot->dq_sb->s_id, ret);
+ /*
+ * We clear dirty bit anyway, so that we avoid
+ * infinite loop here
+ */
+ spin_lock(&dq_list_lock);
+ clear_dquot_dirty(dquot);
+ spin_unlock(&dq_list_lock);
+ }
+ goto we_slept;
+ }
+ /* Clear flag in case dquot was inactive (something bad happened) */
+ clear_dquot_dirty(dquot);
+ if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+ spin_unlock(&dq_list_lock);
+ dquot->dq_sb->dq_op->release_dquot(dquot);
+ goto we_slept;
+ }
+ atomic_dec(&dquot->dq_count);
+#ifdef __DQUOT_PARANOIA
+ /* sanity check */
+ BUG_ON(!list_empty(&dquot->dq_free));
+#endif
+ put_dquot_last(dquot);
+ spin_unlock(&dq_list_lock);
+}
+EXPORT_SYMBOL(dqput);
+
+struct dquot *dquot_alloc(struct super_block *sb, int type)
+{
+ return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
+}
+EXPORT_SYMBOL(dquot_alloc);
+
+static struct dquot *get_empty_dquot(struct super_block *sb, int type)
+{
+ struct dquot *dquot;
+
+ dquot = sb->dq_op->alloc_dquot(sb, type);
+ if(!dquot)
+ return NULL;
+
+ mutex_init(&dquot->dq_lock);
+ INIT_LIST_HEAD(&dquot->dq_free);
+ INIT_LIST_HEAD(&dquot->dq_inuse);
+ INIT_HLIST_NODE(&dquot->dq_hash);
+ INIT_LIST_HEAD(&dquot->dq_dirty);
+ init_waitqueue_head(&dquot->dq_wait_unused);
+ dquot->dq_sb = sb;
+ dquot->dq_type = type;
+ atomic_set(&dquot->dq_count, 1);
+
+ return dquot;
+}
+
+/*
+ * Get reference to dquot
+ *
+ * Locking is slightly tricky here. We are guarded from parallel quotaoff()
+ * destroying our dquot by:
+ * a) checking for quota flags under dq_list_lock and
+ * b) getting a reference to dquot before we release dq_list_lock
+ */
+struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
+{
+ unsigned int hashent = hashfn(sb, id, type);
+ struct dquot *dquot = NULL, *empty = NULL;
+
+ if (!sb_has_quota_active(sb, type))
+ return NULL;
+we_slept:
+ spin_lock(&dq_list_lock);
+ spin_lock(&dq_state_lock);
+ if (!sb_has_quota_active(sb, type)) {
+ spin_unlock(&dq_state_lock);
+ spin_unlock(&dq_list_lock);
+ goto out;
+ }
+ spin_unlock(&dq_state_lock);
+
+ dquot = find_dquot(hashent, sb, id, type);
+ if (!dquot) {
+ if (!empty) {
+ spin_unlock(&dq_list_lock);
+ empty = get_empty_dquot(sb, type);
+ if (!empty)
+ schedule(); /* Try to wait for a moment... */
+ goto we_slept;
+ }
+ dquot = empty;
+ empty = NULL;
+ dquot->dq_id = id;
+ /* all dquots go on the inuse_list */
+ put_inuse(dquot);
+ /* hash it first so it can be found */
+ insert_dquot_hash(dquot);
+ dqstats.lookups++;
+ spin_unlock(&dq_list_lock);
+ } else {
+ if (!atomic_read(&dquot->dq_count))
+ remove_free_dquot(dquot);
+ atomic_inc(&dquot->dq_count);
+ dqstats.cache_hits++;
+ dqstats.lookups++;
+ spin_unlock(&dq_list_lock);
+ }
+ /* Wait for dq_lock - after this we know that either dquot_release() is
+ * already finished or it will be canceled due to dq_count > 1 test */
+ wait_on_dquot(dquot);
+ /* Read the dquot / allocate space in quota file */
+ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) &&
+ sb->dq_op->acquire_dquot(dquot) < 0) {
+ dqput(dquot);
+ dquot = NULL;
+ goto out;
+ }
+#ifdef __DQUOT_PARANOIA
+ BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
+#endif
+out:
+ if (empty)
+ do_destroy_dquot(empty);
+
+ return dquot;
+}
+EXPORT_SYMBOL(dqget);
+
+static int dqinit_needed(struct inode *inode, int type)
+{
+ int cnt;
+
+ if (IS_NOQUOTA(inode))
+ return 0;
+ if (type != -1)
+ return !inode->i_dquot[type];
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (!inode->i_dquot[cnt])
+ return 1;
+ return 0;
+}
+
+/* This routine is guarded by dqonoff_mutex mutex */
+static void add_dquot_ref(struct super_block *sb, int type)
+{
+ struct inode *inode, *old_inode = NULL;
+
+ spin_lock(&inode_lock);
+ list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW))
+ continue;
+ if (!atomic_read(&inode->i_writecount))
+ continue;
+ if (!dqinit_needed(inode, type))
+ continue;
+
+ __iget(inode);
+ spin_unlock(&inode_lock);
+
+ iput(old_inode);
+ sb->dq_op->initialize(inode, type);
+ /* We hold a reference to 'inode' so it couldn't have been
+ * removed from s_inodes list while we dropped the inode_lock.
+ * We cannot iput the inode now as we can be holding the last
+ * reference and we cannot iput it under inode_lock. So we
+ * keep the reference and iput it later. */
+ old_inode = inode;
+ spin_lock(&inode_lock);
+ }
+ spin_unlock(&inode_lock);
+ iput(old_inode);
+}
+
+/*
+ * Return 0 if dqput() won't block.
+ * (note that 1 doesn't necessarily mean blocking)
+ */
+static inline int dqput_blocks(struct dquot *dquot)
+{
+ if (atomic_read(&dquot->dq_count) <= 1)
+ return 1;
+ return 0;
+}
+
+/*
+ * Remove references to dquots from inode and add dquot to list for freeing
+ * if we have the last referece to dquot
+ * We can't race with anybody because we hold dqptr_sem for writing...
+ */
+static int remove_inode_dquot_ref(struct inode *inode, int type,
+ struct list_head *tofree_head)
+{
+ struct dquot *dquot = inode->i_dquot[type];
+
+ inode->i_dquot[type] = NULL;
+ if (dquot) {
+ if (dqput_blocks(dquot)) {
+#ifdef __DQUOT_PARANOIA
+ if (atomic_read(&dquot->dq_count) != 1)
+ printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
+#endif
+ spin_lock(&dq_list_lock);
+ /* As dquot must have currently users it can't be on
+ * the free list... */
+ list_add(&dquot->dq_free, tofree_head);
+ spin_unlock(&dq_list_lock);
+ return 1;
+ }
+ else
+ dqput(dquot); /* We have guaranteed we won't block */
+ }
+ return 0;
+}
+
+/*
+ * Free list of dquots
+ * Dquots are removed from inodes and no new references can be got so we are
+ * the only ones holding reference
+ */
+static void put_dquot_list(struct list_head *tofree_head)
+{
+ struct list_head *act_head;
+ struct dquot *dquot;
+
+ act_head = tofree_head->next;
+ while (act_head != tofree_head) {
+ dquot = list_entry(act_head, struct dquot, dq_free);
+ act_head = act_head->next;
+ /* Remove dquot from the list so we won't have problems... */
+ list_del_init(&dquot->dq_free);
+ dqput(dquot);
+ }
+}
+
+static void remove_dquot_ref(struct super_block *sb, int type,
+ struct list_head *tofree_head)
+{
+ struct inode *inode;
+
+ spin_lock(&inode_lock);
+ list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
+ /*
+ * We have to scan also I_NEW inodes because they can already
+ * have quota pointer initialized. Luckily, we need to touch
+ * only quota pointers and these have separate locking
+ * (dqptr_sem).
+ */
+ if (!IS_NOQUOTA(inode))
+ remove_inode_dquot_ref(inode, type, tofree_head);
+ }
+ spin_unlock(&inode_lock);
+}
+
+/* Gather all references from inodes and drop them */
+static void drop_dquot_ref(struct super_block *sb, int type)
+{
+ LIST_HEAD(tofree_head);
+
+ if (sb->dq_op) {
+ down_write(&sb_dqopt(sb)->dqptr_sem);
+ remove_dquot_ref(sb, type, &tofree_head);
+ up_write(&sb_dqopt(sb)->dqptr_sem);
+ put_dquot_list(&tofree_head);
+ }
+}
+
+static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
+{
+ dquot->dq_dqb.dqb_curinodes += number;
+}
+
+static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
+{
+ dquot->dq_dqb.dqb_curspace += number;
+}
+
+static inline void dquot_resv_space(struct dquot *dquot, qsize_t number)
+{
+ dquot->dq_dqb.dqb_rsvspace += number;
+}
+
+/*
+ * Claim reserved quota space
+ */
+static void dquot_claim_reserved_space(struct dquot *dquot,
+ qsize_t number)
+{
+ WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);
+ dquot->dq_dqb.dqb_curspace += number;
+ dquot->dq_dqb.dqb_rsvspace -= number;
+}
+
+static inline
+void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
+{
+ dquot->dq_dqb.dqb_rsvspace -= number;
+}
+
+static void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
+{
+ if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
+ dquot->dq_dqb.dqb_curinodes >= number)
+ dquot->dq_dqb.dqb_curinodes -= number;
+ else
+ dquot->dq_dqb.dqb_curinodes = 0;
+ if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
+ dquot->dq_dqb.dqb_itime = (time_t) 0;
+ clear_bit(DQ_INODES_B, &dquot->dq_flags);
+}
+
+static void dquot_decr_space(struct dquot *dquot, qsize_t number)
+{
+ if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
+ dquot->dq_dqb.dqb_curspace >= number)
+ dquot->dq_dqb.dqb_curspace -= number;
+ else
+ dquot->dq_dqb.dqb_curspace = 0;
+ if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
+ dquot->dq_dqb.dqb_btime = (time_t) 0;
+ clear_bit(DQ_BLKS_B, &dquot->dq_flags);
+}
+
+static int warning_issued(struct dquot *dquot, const int warntype)
+{
+ int flag = (warntype == QUOTA_NL_BHARDWARN ||
+ warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
+ ((warntype == QUOTA_NL_IHARDWARN ||
+ warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
+
+ if (!flag)
+ return 0;
+ return test_and_set_bit(flag, &dquot->dq_flags);
+}
+
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+static int flag_print_warnings = 1;
+
+static int need_print_warning(struct dquot *dquot)
+{
+ if (!flag_print_warnings)
+ return 0;
+
+ switch (dquot->dq_type) {
+ case USRQUOTA:
+ return current_fsuid() == dquot->dq_id;
+ case GRPQUOTA:
+ return in_group_p(dquot->dq_id);
+ }
+ return 0;
+}
+
+/* Print warning to user which exceeded quota */
+static void print_warning(struct dquot *dquot, const int warntype)
+{
+ char *msg = NULL;
+ struct tty_struct *tty;
+
+ if (warntype == QUOTA_NL_IHARDBELOW ||
+ warntype == QUOTA_NL_ISOFTBELOW ||
+ warntype == QUOTA_NL_BHARDBELOW ||
+ warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot))
+ return;
+
+ tty = get_current_tty();
+ if (!tty)
+ return;
+ tty_write_message(tty, dquot->dq_sb->s_id);
+ if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
+ tty_write_message(tty, ": warning, ");
+ else
+ tty_write_message(tty, ": write failed, ");
+ tty_write_message(tty, quotatypes[dquot->dq_type]);
+ switch (warntype) {
+ case QUOTA_NL_IHARDWARN:
+ msg = " file limit reached.\r\n";
+ break;
+ case QUOTA_NL_ISOFTLONGWARN:
+ msg = " file quota exceeded too long.\r\n";
+ break;
+ case QUOTA_NL_ISOFTWARN:
+ msg = " file quota exceeded.\r\n";
+ break;
+ case QUOTA_NL_BHARDWARN:
+ msg = " block limit reached.\r\n";
+ break;
+ case QUOTA_NL_BSOFTLONGWARN:
+ msg = " block quota exceeded too long.\r\n";
+ break;
+ case QUOTA_NL_BSOFTWARN:
+ msg = " block quota exceeded.\r\n";
+ break;
+ }
+ tty_write_message(tty, msg);
+ tty_kref_put(tty);
+}
+#endif
+
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+
+/* Netlink family structure for quota */
+static struct genl_family quota_genl_family = {
+ .id = GENL_ID_GENERATE,
+ .hdrsize = 0,
+ .name = "VFS_DQUOT",
+ .version = 1,
+ .maxattr = QUOTA_NL_A_MAX,
+};
+
+/* Send warning to userspace about user which exceeded quota */
+static void send_warning(const struct dquot *dquot, const char warntype)
+{
+ static atomic_t seq;
+ struct sk_buff *skb;
+ void *msg_head;
+ int ret;
+ int msg_size = 4 * nla_total_size(sizeof(u32)) +
+ 2 * nla_total_size(sizeof(u64));
+
+ /* We have to allocate using GFP_NOFS as we are called from a
+ * filesystem performing write and thus further recursion into
+ * the fs to free some data could cause deadlocks. */
+ skb = genlmsg_new(msg_size, GFP_NOFS);
+ if (!skb) {
+ printk(KERN_ERR
+ "VFS: Not enough memory to send quota warning.\n");
+ return;
+ }
+ msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
+ &quota_genl_family, 0, QUOTA_NL_C_WARNING);
+ if (!msg_head) {
+ printk(KERN_ERR
+ "VFS: Cannot store netlink header in quota warning.\n");
+ goto err_out;
+ }
+ ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
+ if (ret)
+ goto attr_err_out;
+ ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
+ if (ret)
+ goto attr_err_out;
+ ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
+ if (ret)
+ goto attr_err_out;
+ ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
+ MAJOR(dquot->dq_sb->s_dev));
+ if (ret)
+ goto attr_err_out;
+ ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
+ MINOR(dquot->dq_sb->s_dev));
+ if (ret)
+ goto attr_err_out;
+ ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
+ if (ret)
+ goto attr_err_out;
+ genlmsg_end(skb, msg_head);
+
+ genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
+ return;
+attr_err_out:
+ printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
+err_out:
+ kfree_skb(skb);
+}
+#endif
+/*
+ * Write warnings to the console and send warning messages over netlink.
+ *
+ * Note that this function can sleep.
+ */
+static void flush_warnings(struct dquot *const *dquots, char *warntype)
+{
+ int i;
+
+ for (i = 0; i < MAXQUOTAS; i++)
+ if (dquots[i] && warntype[i] != QUOTA_NL_NOWARN &&
+ !warning_issued(dquots[i], warntype[i])) {
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+ print_warning(dquots[i], warntype[i]);
+#endif
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+ send_warning(dquots[i], warntype[i]);
+#endif
+ }
+}
+
+static int ignore_hardlimit(struct dquot *dquot)
+{
+ struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
+
+ return capable(CAP_SYS_RESOURCE) &&
+ (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||
+ !(info->dqi_flags & V1_DQF_RSQUASH));
+}
+
+/* needs dq_data_lock */
+static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype)
+{
+ qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes;
+
+ *warntype = QUOTA_NL_NOWARN;
+ if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) ||
+ test_bit(DQ_FAKE_B, &dquot->dq_flags))
+ return QUOTA_OK;
+
+ if (dquot->dq_dqb.dqb_ihardlimit &&
+ newinodes > dquot->dq_dqb.dqb_ihardlimit &&
+ !ignore_hardlimit(dquot)) {
+ *warntype = QUOTA_NL_IHARDWARN;
+ return NO_QUOTA;
+ }
+
+ if (dquot->dq_dqb.dqb_isoftlimit &&
+ newinodes > dquot->dq_dqb.dqb_isoftlimit &&
+ dquot->dq_dqb.dqb_itime &&
+ get_seconds() >= dquot->dq_dqb.dqb_itime &&
+ !ignore_hardlimit(dquot)) {
+ *warntype = QUOTA_NL_ISOFTLONGWARN;
+ return NO_QUOTA;
+ }
+
+ if (dquot->dq_dqb.dqb_isoftlimit &&
+ newinodes > dquot->dq_dqb.dqb_isoftlimit &&
+ dquot->dq_dqb.dqb_itime == 0) {
+ *warntype = QUOTA_NL_ISOFTWARN;
+ dquot->dq_dqb.dqb_itime = get_seconds() +
+ sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
+ }
+
+ return QUOTA_OK;
+}
+
+/* needs dq_data_lock */
+static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
+{
+ qsize_t tspace;
+ struct super_block *sb = dquot->dq_sb;
+
+ *warntype = QUOTA_NL_NOWARN;
+ if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) ||
+ test_bit(DQ_FAKE_B, &dquot->dq_flags))
+ return QUOTA_OK;
+
+ tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
+ + space;
+
+ if (dquot->dq_dqb.dqb_bhardlimit &&
+ tspace > dquot->dq_dqb.dqb_bhardlimit &&
+ !ignore_hardlimit(dquot)) {
+ if (!prealloc)
+ *warntype = QUOTA_NL_BHARDWARN;
+ return NO_QUOTA;
+ }
+
+ if (dquot->dq_dqb.dqb_bsoftlimit &&
+ tspace > dquot->dq_dqb.dqb_bsoftlimit &&
+ dquot->dq_dqb.dqb_btime &&
+ get_seconds() >= dquot->dq_dqb.dqb_btime &&
+ !ignore_hardlimit(dquot)) {
+ if (!prealloc)
+ *warntype = QUOTA_NL_BSOFTLONGWARN;
+ return NO_QUOTA;
+ }
+
+ if (dquot->dq_dqb.dqb_bsoftlimit &&
+ tspace > dquot->dq_dqb.dqb_bsoftlimit &&
+ dquot->dq_dqb.dqb_btime == 0) {
+ if (!prealloc) {
+ *warntype = QUOTA_NL_BSOFTWARN;
+ dquot->dq_dqb.dqb_btime = get_seconds() +
+ sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace;
+ }
+ else
+ /*
+ * We don't allow preallocation to exceed softlimit so exceeding will
+ * be always printed
+ */
+ return NO_QUOTA;
+ }
+
+ return QUOTA_OK;
+}
+
+static int info_idq_free(struct dquot *dquot, qsize_t inodes)
+{
+ qsize_t newinodes;
+
+ if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
+ dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
+ !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type))
+ return QUOTA_NL_NOWARN;
+
+ newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
+ if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)
+ return QUOTA_NL_ISOFTBELOW;
+ if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
+ newinodes < dquot->dq_dqb.dqb_ihardlimit)
+ return QUOTA_NL_IHARDBELOW;
+ return QUOTA_NL_NOWARN;
+}
+
+static int info_bdq_free(struct dquot *dquot, qsize_t space)
+{
+ if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
+ dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
+ return QUOTA_NL_NOWARN;
+
+ if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
+ return QUOTA_NL_BSOFTBELOW;
+ if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
+ dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
+ return QUOTA_NL_BHARDBELOW;
+ return QUOTA_NL_NOWARN;
+}
+/*
+ * Initialize quota pointers in inode
+ * We do things in a bit complicated way but by that we avoid calling
+ * dqget() and thus filesystem callbacks under dqptr_sem.
+ */
+int dquot_initialize(struct inode *inode, int type)
+{
+ unsigned int id = 0;
+ int cnt, ret = 0;
+ struct dquot *got[MAXQUOTAS] = { NULL, NULL };
+ struct super_block *sb = inode->i_sb;
+
+ /* First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex */
+ if (IS_NOQUOTA(inode))
+ return 0;
+
+ /* First get references to structures we might need. */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (type != -1 && cnt != type)
+ continue;
+ switch (cnt) {
+ case USRQUOTA:
+ id = inode->i_uid;
+ break;
+ case GRPQUOTA:
+ id = inode->i_gid;
+ break;
+ }
+ got[cnt] = dqget(sb, id, cnt);
+ }
+
+ down_write(&sb_dqopt(sb)->dqptr_sem);
+ /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
+ if (IS_NOQUOTA(inode))
+ goto out_err;
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (type != -1 && cnt != type)
+ continue;
+ /* Avoid races with quotaoff() */
+ if (!sb_has_quota_active(sb, cnt))
+ continue;
+ if (!inode->i_dquot[cnt]) {
+ inode->i_dquot[cnt] = got[cnt];
+ got[cnt] = NULL;
+ }
+ }
+out_err:
+ up_write(&sb_dqopt(sb)->dqptr_sem);
+ /* Drop unused references */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ dqput(got[cnt]);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_initialize);
+
+/*
+ * Release all quotas referenced by inode
+ */
+int dquot_drop(struct inode *inode)
+{
+ int cnt;
+ struct dquot *put[MAXQUOTAS];
+
+ down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ put[cnt] = inode->i_dquot[cnt];
+ inode->i_dquot[cnt] = NULL;
+ }
+ up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ dqput(put[cnt]);
+ return 0;
+}
+EXPORT_SYMBOL(dquot_drop);
+
+/* Wrapper to remove references to quota structures from inode */
+void vfs_dq_drop(struct inode *inode)
+{
+ /* Here we can get arbitrary inode from clear_inode() so we have
+ * to be careful. OTOH we don't need locking as quota operations
+ * are allowed to change only at mount time */
+ if (!IS_NOQUOTA(inode) && inode->i_sb && inode->i_sb->dq_op
+ && inode->i_sb->dq_op->drop) {
+ int cnt;
+ /* Test before calling to rule out calls from proc and such
+ * where we are not allowed to block. Note that this is
+ * actually reliable test even without the lock - the caller
+ * must assure that nobody can come after the DQUOT_DROP and
+ * add quota pointers back anyway */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ break;
+ if (cnt < MAXQUOTAS)
+ inode->i_sb->dq_op->drop(inode);
+ }
+}
+EXPORT_SYMBOL(vfs_dq_drop);
+
+/*
+ * Following four functions update i_blocks+i_bytes fields and
+ * quota information (together with appropriate checks)
+ * NOTE: We absolutely rely on the fact that caller dirties
+ * the inode (usually macros in quotaops.h care about this) and
+ * holds a handle for the current transaction so that dquot write and
+ * inode write go into the same transaction.
+ */
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int __dquot_alloc_space(struct inode *inode, qsize_t number,
+ int warn, int reserve)
+{
+ int cnt, ret = QUOTA_OK;
+ char warntype[MAXQUOTAS];
+
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ warntype[cnt] = QUOTA_NL_NOWARN;
+
+ spin_lock(&dq_data_lock);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt)
+ == NO_QUOTA) {
+ ret = NO_QUOTA;
+ goto out_unlock;
+ }
+ }
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ if (reserve)
+ dquot_resv_space(inode->i_dquot[cnt], number);
+ else
+ dquot_incr_space(inode->i_dquot[cnt], number);
+ }
+ if (!reserve)
+ inode_add_bytes(inode, number);
+out_unlock:
+ spin_unlock(&dq_data_lock);
+ flush_warnings(inode->i_dquot, warntype);
+ return ret;
+}
+
+int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
+{
+ int cnt, ret = QUOTA_OK;
+
+ /*
+ * First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex
+ */
+ if (IS_NOQUOTA(inode)) {
+ inode_add_bytes(inode, number);
+ goto out;
+ }
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode)) {
+ inode_add_bytes(inode, number);
+ goto out_unlock;
+ }
+
+ ret = __dquot_alloc_space(inode, number, warn, 0);
+ if (ret == NO_QUOTA)
+ goto out_unlock;
+
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+out_unlock:
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+ return ret;
+}
+EXPORT_SYMBOL(dquot_alloc_space);
+
+int dquot_reserve_space(struct inode *inode, qsize_t number, int warn)
+{
+ int ret = QUOTA_OK;
+
+ if (IS_NOQUOTA(inode))
+ goto out;
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode))
+ goto out_unlock;
+
+ ret = __dquot_alloc_space(inode, number, warn, 1);
+out_unlock:
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+ return ret;
+}
+EXPORT_SYMBOL(dquot_reserve_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_alloc_inode(const struct inode *inode, qsize_t number)
+{
+ int cnt, ret = NO_QUOTA;
+ char warntype[MAXQUOTAS];
+
+ /* First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex */
+ if (IS_NOQUOTA(inode))
+ return QUOTA_OK;
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ warntype[cnt] = QUOTA_NL_NOWARN;
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return QUOTA_OK;
+ }
+ spin_lock(&dq_data_lock);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ if (check_idq(inode->i_dquot[cnt], number, warntype+cnt)
+ == NO_QUOTA)
+ goto warn_put_all;
+ }
+
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ dquot_incr_inodes(inode->i_dquot[cnt], number);
+ }
+ ret = QUOTA_OK;
+warn_put_all:
+ spin_unlock(&dq_data_lock);
+ if (ret == QUOTA_OK)
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+ flush_warnings(inode->i_dquot, warntype);
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_alloc_inode);
+
+int dquot_claim_space(struct inode *inode, qsize_t number)
+{
+ int cnt;
+ int ret = QUOTA_OK;
+
+ if (IS_NOQUOTA(inode)) {
+ inode_add_bytes(inode, number);
+ goto out;
+ }
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ inode_add_bytes(inode, number);
+ goto out;
+ }
+
+ spin_lock(&dq_data_lock);
+ /* Claim reserved quotas to allocated quotas */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (inode->i_dquot[cnt])
+ dquot_claim_reserved_space(inode->i_dquot[cnt],
+ number);
+ }
+ /* Update inode bytes */
+ inode_add_bytes(inode, number);
+ spin_unlock(&dq_data_lock);
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+ return ret;
+}
+EXPORT_SYMBOL(dquot_claim_space);
+
+/*
+ * Release reserved quota space
+ */
+void dquot_release_reserved_space(struct inode *inode, qsize_t number)
+{
+ int cnt;
+
+ if (IS_NOQUOTA(inode))
+ goto out;
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode))
+ goto out_unlock;
+
+ spin_lock(&dq_data_lock);
+ /* Release reserved dquots */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (inode->i_dquot[cnt])
+ dquot_free_reserved_space(inode->i_dquot[cnt], number);
+ }
+ spin_unlock(&dq_data_lock);
+
+out_unlock:
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+ return;
+}
+EXPORT_SYMBOL(dquot_release_reserved_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_free_space(struct inode *inode, qsize_t number)
+{
+ unsigned int cnt;
+ char warntype[MAXQUOTAS];
+
+ /* First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex */
+ if (IS_NOQUOTA(inode)) {
+out_sub:
+ inode_sub_bytes(inode, number);
+ return QUOTA_OK;
+ }
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ /* Now recheck reliably when holding dqptr_sem */
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ goto out_sub;
+ }
+ spin_lock(&dq_data_lock);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number);
+ dquot_decr_space(inode->i_dquot[cnt], number);
+ }
+ inode_sub_bytes(inode, number);
+ spin_unlock(&dq_data_lock);
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+ flush_warnings(inode->i_dquot, warntype);
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return QUOTA_OK;
+}
+EXPORT_SYMBOL(dquot_free_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_free_inode(const struct inode *inode, qsize_t number)
+{
+ unsigned int cnt;
+ char warntype[MAXQUOTAS];
+
+ /* First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex */
+ if (IS_NOQUOTA(inode))
+ return QUOTA_OK;
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ /* Now recheck reliably when holding dqptr_sem */
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return QUOTA_OK;
+ }
+ spin_lock(&dq_data_lock);
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!inode->i_dquot[cnt])
+ continue;
+ warntype[cnt] = info_idq_free(inode->i_dquot[cnt], number);
+ dquot_decr_inodes(inode->i_dquot[cnt], number);
+ }
+ spin_unlock(&dq_data_lock);
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+ flush_warnings(inode->i_dquot, warntype);
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return QUOTA_OK;
+}
+EXPORT_SYMBOL(dquot_free_inode);
+
+/*
+ * call back function, get reserved quota space from underlying fs
+ */
+qsize_t dquot_get_reserved_space(struct inode *inode)
+{
+ qsize_t reserved_space = 0;
+
+ if (sb_any_quota_active(inode->i_sb) &&
+ inode->i_sb->dq_op->get_reserved_space)
+ reserved_space = inode->i_sb->dq_op->get_reserved_space(inode);
+ return reserved_space;
+}
+
+/*
+ * Transfer the number of inode and blocks from one diskquota to an other.
+ *
+ * This operation can block, but only after everything is updated
+ * A transaction must be started when entering this function.
+ */
+int dquot_transfer(struct inode *inode, struct iattr *iattr)
+{
+ qsize_t space, cur_space;
+ qsize_t rsv_space = 0;
+ struct dquot *transfer_from[MAXQUOTAS];
+ struct dquot *transfer_to[MAXQUOTAS];
+ int cnt, ret = QUOTA_OK;
+ int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid,
+ chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid;
+ char warntype_to[MAXQUOTAS];
+ char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
+
+ /* First test before acquiring mutex - solves deadlocks when we
+ * re-enter the quota code and are already holding the mutex */
+ if (IS_NOQUOTA(inode))
+ return QUOTA_OK;
+ /* Initialize the arrays */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ transfer_from[cnt] = NULL;
+ transfer_to[cnt] = NULL;
+ warntype_to[cnt] = QUOTA_NL_NOWARN;
+ }
+ if (chuid)
+ transfer_to[USRQUOTA] = dqget(inode->i_sb, iattr->ia_uid,
+ USRQUOTA);
+ if (chgid)
+ transfer_to[GRPQUOTA] = dqget(inode->i_sb, iattr->ia_gid,
+ GRPQUOTA);
+
+ down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ /* Now recheck reliably when holding dqptr_sem */
+ if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
+ up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ goto put_all;
+ }
+ spin_lock(&dq_data_lock);
+ cur_space = inode_get_bytes(inode);
+ rsv_space = dquot_get_reserved_space(inode);
+ space = cur_space + rsv_space;
+ /* Build the transfer_from list and check the limits */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (!transfer_to[cnt])
+ continue;
+ transfer_from[cnt] = inode->i_dquot[cnt];
+ if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
+ NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
+ warntype_to + cnt) == NO_QUOTA)
+ goto over_quota;
+ }
+
+ /*
+ * Finally perform the needed transfer from transfer_from to transfer_to
+ */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ /*
+ * Skip changes for same uid or gid or for turned off quota-type.
+ */
+ if (!transfer_to[cnt])
+ continue;
+
+ /* Due to IO error we might not have transfer_from[] structure */
+ if (transfer_from[cnt]) {
+ warntype_from_inodes[cnt] =
+ info_idq_free(transfer_from[cnt], 1);
+ warntype_from_space[cnt] =
+ info_bdq_free(transfer_from[cnt], space);
+ dquot_decr_inodes(transfer_from[cnt], 1);
+ dquot_decr_space(transfer_from[cnt], cur_space);
+ dquot_free_reserved_space(transfer_from[cnt],
+ rsv_space);
+ }
+
+ dquot_incr_inodes(transfer_to[cnt], 1);
+ dquot_incr_space(transfer_to[cnt], cur_space);
+ dquot_resv_space(transfer_to[cnt], rsv_space);
+
+ inode->i_dquot[cnt] = transfer_to[cnt];
+ }
+ spin_unlock(&dq_data_lock);
+ up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (transfer_from[cnt])
+ mark_dquot_dirty(transfer_from[cnt]);
+ if (transfer_to[cnt]) {
+ mark_dquot_dirty(transfer_to[cnt]);
+ /* The reference we got is transferred to the inode */
+ transfer_to[cnt] = NULL;
+ }
+ }
+warn_put_all:
+ flush_warnings(transfer_to, warntype_to);
+ flush_warnings(transfer_from, warntype_from_inodes);
+ flush_warnings(transfer_from, warntype_from_space);
+put_all:
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ dqput(transfer_from[cnt]);
+ dqput(transfer_to[cnt]);
+ }
+ return ret;
+over_quota:
+ spin_unlock(&dq_data_lock);
+ 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] = NULL;
+ ret = NO_QUOTA;
+ goto warn_put_all;
+}
+EXPORT_SYMBOL(dquot_transfer);
+
+/* Wrapper for transferring ownership of an inode */
+int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
+{
+ if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
+ vfs_dq_init(inode);
+ if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA)
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(vfs_dq_transfer);
+
+/*
+ * Write info of quota file to disk
+ */
+int dquot_commit_info(struct super_block *sb, int type)
+{
+ int ret;
+ struct quota_info *dqopt = sb_dqopt(sb);
+
+ mutex_lock(&dqopt->dqio_mutex);
+ ret = dqopt->ops[type]->write_file_info(sb, type);
+ mutex_unlock(&dqopt->dqio_mutex);
+ return ret;
+}
+EXPORT_SYMBOL(dquot_commit_info);
+
+/*
+ * Definitions of diskquota operations.
+ */
+struct dquot_operations dquot_operations = {
+ .initialize = dquot_initialize,
+ .drop = dquot_drop,
+ .alloc_space = dquot_alloc_space,
+ .alloc_inode = dquot_alloc_inode,
+ .free_space = dquot_free_space,
+ .free_inode = dquot_free_inode,
+ .transfer = dquot_transfer,
+ .write_dquot = dquot_commit,
+ .acquire_dquot = dquot_acquire,
+ .release_dquot = dquot_release,
+ .mark_dirty = dquot_mark_dquot_dirty,
+ .write_info = dquot_commit_info,
+ .alloc_dquot = dquot_alloc,
+ .destroy_dquot = dquot_destroy,
+};
+
+/*
+ * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
+ */
+int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags)
+{
+ int cnt, ret = 0;
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct inode *toputinode[MAXQUOTAS];
+
+ /* Cannot turn off usage accounting without turning off limits, or
+ * suspend quotas and simultaneously turn quotas off. */
+ if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
+ || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
+ DQUOT_USAGE_ENABLED)))
+ return -EINVAL;
+
+ /* We need to serialize quota_off() for device */
+ mutex_lock(&dqopt->dqonoff_mutex);
+
+ /*
+ * Skip everything if there's nothing to do. We have to do this because
+ * sometimes we are called when fill_super() failed and calling
+ * sync_fs() in such cases does no good.
+ */
+ if (!sb_any_quota_loaded(sb)) {
+ mutex_unlock(&dqopt->dqonoff_mutex);
+ return 0;
+ }
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ toputinode[cnt] = NULL;
+ if (type != -1 && cnt != type)
+ continue;
+ if (!sb_has_quota_loaded(sb, cnt))
+ 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? */
+ if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
+ continue;
+
+ /* Note: these are blocking operations */
+ drop_dquot_ref(sb, cnt);
+ invalidate_dquots(sb, cnt);
+ /*
+ * Now all dquots should be invalidated, all writes done so we
+ * should be only users of the info. No locks needed.
+ */
+ if (info_dirty(&dqopt->info[cnt]))
+ sb->dq_op->write_info(sb, cnt);
+ if (dqopt->ops[cnt]->free_file_info)
+ dqopt->ops[cnt]->free_file_info(sb, cnt);
+ put_quota_format(dqopt->info[cnt].dqi_format);
+
+ toputinode[cnt] = dqopt->files[cnt];
+ if (!sb_has_quota_loaded(sb, cnt))
+ dqopt->files[cnt] = NULL;
+ dqopt->info[cnt].dqi_flags = 0;
+ dqopt->info[cnt].dqi_igrace = 0;
+ dqopt->info[cnt].dqi_bgrace = 0;
+ dqopt->ops[cnt] = NULL;
+ }
+ mutex_unlock(&dqopt->dqonoff_mutex);
+
+ /* Skip syncing and setting flags if quota files are hidden */
+ if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
+ goto put_inodes;
+
+ /* Sync the superblock so that buffers with quota data are written to
+ * disk (and so userspace sees correct data afterwards). */
+ if (sb->s_op->sync_fs)
+ sb->s_op->sync_fs(sb, 1);
+ sync_blockdev(sb->s_bdev);
+ /* Now the quota files are just ordinary files and we can set the
+ * inode flags back. Moreover we discard the pagecache so that
+ * userspace sees the writes we did bypassing the pagecache. We
+ * must also discard the blockdev buffers so that we see the
+ * changes done by userspace on the next quotaon() */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (toputinode[cnt]) {
+ mutex_lock(&dqopt->dqonoff_mutex);
+ /* If quota was reenabled in the meantime, we have
+ * nothing to do */
+ if (!sb_has_quota_loaded(sb, cnt)) {
+ mutex_lock_nested(&toputinode[cnt]->i_mutex,
+ I_MUTEX_QUOTA);
+ toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
+ S_NOATIME | S_NOQUOTA);
+ truncate_inode_pages(&toputinode[cnt]->i_data,
+ 0);
+ mutex_unlock(&toputinode[cnt]->i_mutex);
+ mark_inode_dirty(toputinode[cnt]);
+ }
+ mutex_unlock(&dqopt->dqonoff_mutex);
+ }
+ if (sb->s_bdev)
+ invalidate_bdev(sb->s_bdev);
+put_inodes:
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (toputinode[cnt]) {
+ /* On remount RO, we keep the inode pointer so that we
+ * can reenable quota on the subsequent remount RW. We
+ * have to check 'flags' variable and not use sb_has_
+ * function because another quotaon / quotaoff could
+ * change global state before we got here. We refuse
+ * to suspend quotas when there is pending delete on
+ * the quota file... */
+ if (!(flags & DQUOT_SUSPENDED))
+ iput(toputinode[cnt]);
+ else if (!toputinode[cnt]->i_nlink)
+ ret = -EBUSY;
+ }
+ return ret;
+}
+EXPORT_SYMBOL(vfs_quota_disable);
+
+int vfs_quota_off(struct super_block *sb, int type, int remount)
+{
+ return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED :
+ (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED));
+}
+EXPORT_SYMBOL(vfs_quota_off);
+/*
+ * Turn quotas on on a device
+ */
+
+/*
+ * Helper function to turn quotas on when we already have the inode of
+ * quota file and no quota information is loaded.
+ */
+static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
+ unsigned int flags)
+{
+ struct quota_format_type *fmt = find_quota_format(format_id);
+ struct super_block *sb = inode->i_sb;
+ struct quota_info *dqopt = sb_dqopt(sb);
+ int error;
+ int oldflags = -1;
+
+ if (!fmt)
+ return -ESRCH;
+ if (!S_ISREG(inode->i_mode)) {
+ error = -EACCES;
+ goto out_fmt;
+ }
+ if (IS_RDONLY(inode)) {
+ error = -EROFS;
+ goto out_fmt;
+ }
+ if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
+ error = -EINVAL;
+ goto out_fmt;
+ }
+ /* Usage always has to be set... */
+ if (!(flags & DQUOT_USAGE_ENABLED)) {
+ error = -EINVAL;
+ goto out_fmt;
+ }
+
+ if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
+ /* As we bypass the pagecache we must now flush the inode so
+ * that we see all the changes from userspace... */
+ write_inode_now(inode, 1);
+ /* And now flush the block cache so that kernel sees the
+ * changes */
+ invalidate_bdev(sb->s_bdev);
+ }
+ mutex_lock(&inode->i_mutex);
+ mutex_lock(&dqopt->dqonoff_mutex);
+ if (sb_has_quota_loaded(sb, type)) {
+ error = -EBUSY;
+ goto out_lock;
+ }
+
+ if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
+ /* We don't want quota and atime on quota files (deadlocks
+ * possible) Also nobody should write to the file - we use
+ * special IO operations which ignore the immutable bit. */
+ down_write(&dqopt->dqptr_sem);
+ oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE |
+ S_NOQUOTA);
+ inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
+ up_write(&dqopt->dqptr_sem);
+ sb->dq_op->drop(inode);
+ }
+
+ error = -EIO;
+ dqopt->files[type] = igrab(inode);
+ if (!dqopt->files[type])
+ goto out_lock;
+ error = -EINVAL;
+ if (!fmt->qf_ops->check_quota_file(sb, type))
+ goto out_file_init;
+
+ dqopt->ops[type] = fmt->qf_ops;
+ dqopt->info[type].dqi_format = fmt;
+ dqopt->info[type].dqi_fmt_id = format_id;
+ INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
+ mutex_lock(&dqopt->dqio_mutex);
+ error = dqopt->ops[type]->read_file_info(sb, type);
+ if (error < 0) {
+ mutex_unlock(&dqopt->dqio_mutex);
+ goto out_file_init;
+ }
+ 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);
+
+ return 0;
+
+out_file_init:
+ dqopt->files[type] = NULL;
+ iput(inode);
+out_lock:
+ mutex_unlock(&dqopt->dqonoff_mutex);
+ if (oldflags != -1) {
+ down_write(&dqopt->dqptr_sem);
+ /* Set the flags back (in the case of accidental quotaon()
+ * on a wrong file we don't want to mess up the flags) */
+ inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
+ inode->i_flags |= oldflags;
+ up_write(&dqopt->dqptr_sem);
+ }
+ mutex_unlock(&inode->i_mutex);
+out_fmt:
+ put_quota_format(fmt);
+
+ return error;
+}
+
+/* Reenable quotas on remount RW */
+static int vfs_quota_on_remount(struct super_block *sb, int type)
+{
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct inode *inode;
+ int ret;
+ unsigned int flags;
+
+ mutex_lock(&dqopt->dqonoff_mutex);
+ if (!sb_has_quota_suspended(sb, type)) {
+ mutex_unlock(&dqopt->dqonoff_mutex);
+ return 0;
+ }
+ 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);
+ ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id,
+ flags);
+ iput(inode);
+
+ return ret;
+}
+
+int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
+ struct path *path)
+{
+ int error = security_quota_on(path->dentry);
+ if (error)
+ return error;
+ /* Quota file not on the same filesystem? */
+ if (path->mnt->mnt_sb != sb)
+ error = -EXDEV;
+ else
+ error = vfs_load_quota_inode(path->dentry->d_inode, type,
+ format_id, DQUOT_USAGE_ENABLED |
+ DQUOT_LIMITS_ENABLED);
+ return error;
+}
+EXPORT_SYMBOL(vfs_quota_on_path);
+
+int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name,
+ int remount)
+{
+ struct path path;
+ int error;
+
+ if (remount)
+ return vfs_quota_on_remount(sb, type);
+
+ error = kern_path(name, LOOKUP_FOLLOW, &path);
+ if (!error) {
+ error = vfs_quota_on_path(sb, type, format_id, &path);
+ path_put(&path);
+ }
+ return error;
+}
+EXPORT_SYMBOL(vfs_quota_on);
+
+/*
+ * More powerful function for turning on quotas allowing setting
+ * of individual quota flags
+ */
+int vfs_quota_enable(struct inode *inode, int type, int format_id,
+ unsigned int flags)
+{
+ int ret = 0;
+ struct super_block *sb = inode->i_sb;
+ struct quota_info *dqopt = sb_dqopt(sb);
+
+ /* Just unsuspend quotas? */
+ if (flags & DQUOT_SUSPENDED)
+ return vfs_quota_on_remount(sb, type);
+ if (!flags)
+ return 0;
+ /* Just updating flags needed? */
+ if (sb_has_quota_loaded(sb, type)) {
+ mutex_lock(&dqopt->dqonoff_mutex);
+ /* Now do a reliable test... */
+ if (!sb_has_quota_loaded(sb, type)) {
+ mutex_unlock(&dqopt->dqonoff_mutex);
+ goto load_quota;
+ }
+ if (flags & DQUOT_USAGE_ENABLED &&
+ sb_has_quota_usage_enabled(sb, type)) {
+ ret = -EBUSY;
+ goto out_lock;
+ }
+ if (flags & DQUOT_LIMITS_ENABLED &&
+ sb_has_quota_limits_enabled(sb, type)) {
+ 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;
+ }
+
+load_quota:
+ return vfs_load_quota_inode(inode, type, format_id, flags);
+}
+EXPORT_SYMBOL(vfs_quota_enable);
+
+/*
+ * This function is used when filesystem needs to initialize quotas
+ * during mount time.
+ */
+int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
+ int format_id, int type)
+{
+ struct dentry *dentry;
+ int error;
+
+ dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+
+ if (!dentry->d_inode) {
+ error = -ENOENT;
+ goto out;
+ }
+
+ error = security_quota_on(dentry);
+ if (!error)
+ error = vfs_load_quota_inode(dentry->d_inode, type, format_id,
+ DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
+
+out:
+ dput(dentry);
+ return error;
+}
+EXPORT_SYMBOL(vfs_quota_on_mount);
+
+/* Wrapper to turn on quotas when remounting rw */
+int vfs_dq_quota_on_remount(struct super_block *sb)
+{
+ int cnt;
+ int ret = 0, err;
+
+ if (!sb->s_qcop || !sb->s_qcop->quota_on)
+ return -ENOSYS;
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1);
+ if (err < 0 && !ret)
+ ret = err;
+ }
+ return ret;
+}
+EXPORT_SYMBOL(vfs_dq_quota_on_remount);
+
+static inline qsize_t qbtos(qsize_t blocks)
+{
+ return blocks << QIF_DQBLKSIZE_BITS;
+}
+
+static inline qsize_t stoqb(qsize_t space)
+{
+ return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
+}
+
+/* Generic routine for getting common part of quota structure */
+static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
+{
+ struct mem_dqblk *dm = &dquot->dq_dqb;
+
+ spin_lock(&dq_data_lock);
+ di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
+ di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
+ di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace;
+ di->dqb_ihardlimit = dm->dqb_ihardlimit;
+ di->dqb_isoftlimit = dm->dqb_isoftlimit;
+ di->dqb_curinodes = dm->dqb_curinodes;
+ di->dqb_btime = dm->dqb_btime;
+ di->dqb_itime = dm->dqb_itime;
+ di->dqb_valid = QIF_ALL;
+ spin_unlock(&dq_data_lock);
+}
+
+int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
+ struct if_dqblk *di)
+{
+ struct dquot *dquot;
+
+ dquot = dqget(sb, id, type);
+ if (!dquot)
+ return -ESRCH;
+ do_get_dqblk(dquot, di);
+ dqput(dquot);
+
+ return 0;
+}
+EXPORT_SYMBOL(vfs_get_dqblk);
+
+/* Generic routine for setting common part of quota structure */
+static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
+{
+ struct mem_dqblk *dm = &dquot->dq_dqb;
+ int check_blim = 0, check_ilim = 0;
+ struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
+
+ if ((di->dqb_valid & QIF_BLIMITS &&
+ (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
+ di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
+ (di->dqb_valid & QIF_ILIMITS &&
+ (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
+ di->dqb_isoftlimit > dqi->dqi_maxilimit)))
+ return -ERANGE;
+
+ spin_lock(&dq_data_lock);
+ if (di->dqb_valid & QIF_SPACE) {
+ dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace;
+ check_blim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
+ }
+ if (di->dqb_valid & QIF_BLIMITS) {
+ dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
+ dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
+ check_blim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
+ }
+ if (di->dqb_valid & QIF_INODES) {
+ dm->dqb_curinodes = di->dqb_curinodes;
+ check_ilim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
+ }
+ if (di->dqb_valid & QIF_ILIMITS) {
+ dm->dqb_isoftlimit = di->dqb_isoftlimit;
+ dm->dqb_ihardlimit = di->dqb_ihardlimit;
+ check_ilim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
+ }
+ if (di->dqb_valid & QIF_BTIME) {
+ dm->dqb_btime = di->dqb_btime;
+ check_blim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
+ }
+ if (di->dqb_valid & QIF_ITIME) {
+ dm->dqb_itime = di->dqb_itime;
+ check_ilim = 1;
+ __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
+ }
+
+ if (check_blim) {
+ if (!dm->dqb_bsoftlimit ||
+ dm->dqb_curspace < dm->dqb_bsoftlimit) {
+ dm->dqb_btime = 0;
+ clear_bit(DQ_BLKS_B, &dquot->dq_flags);
+ } else if (!(di->dqb_valid & QIF_BTIME))
+ /* Set grace only if user hasn't provided his own... */
+ dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
+ }
+ if (check_ilim) {
+ if (!dm->dqb_isoftlimit ||
+ dm->dqb_curinodes < dm->dqb_isoftlimit) {
+ dm->dqb_itime = 0;
+ clear_bit(DQ_INODES_B, &dquot->dq_flags);
+ } else if (!(di->dqb_valid & QIF_ITIME))
+ /* Set grace only if user hasn't provided his own... */
+ dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
+ }
+ if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit ||
+ dm->dqb_isoftlimit)
+ clear_bit(DQ_FAKE_B, &dquot->dq_flags);
+ else
+ set_bit(DQ_FAKE_B, &dquot->dq_flags);
+ spin_unlock(&dq_data_lock);
+ mark_dquot_dirty(dquot);
+
+ return 0;
+}
+
+int vfs_set_dqblk(struct super_block *sb, int type, qid_t id,
+ struct if_dqblk *di)
+{
+ struct dquot *dquot;
+ int rc;
+
+ dquot = dqget(sb, id, type);
+ if (!dquot) {
+ rc = -ESRCH;
+ goto out;
+ }
+ rc = do_set_dqblk(dquot, di);
+ dqput(dquot);
+out:
+ return rc;
+}
+EXPORT_SYMBOL(vfs_set_dqblk);
+
+/* Generic routine for getting common part of quota file information */
+int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
+{
+ struct mem_dqinfo *mi;
+
+ mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+ if (!sb_has_quota_active(sb, type)) {
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+ return -ESRCH;
+ }
+ mi = sb_dqopt(sb)->info + type;
+ spin_lock(&dq_data_lock);
+ ii->dqi_bgrace = mi->dqi_bgrace;
+ ii->dqi_igrace = mi->dqi_igrace;
+ ii->dqi_flags = mi->dqi_flags & DQF_MASK;
+ ii->dqi_valid = IIF_ALL;
+ spin_unlock(&dq_data_lock);
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+ return 0;
+}
+EXPORT_SYMBOL(vfs_get_dqinfo);
+
+/* Generic routine for setting common part of quota file information */
+int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
+{
+ struct mem_dqinfo *mi;
+ int err = 0;
+
+ mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+ if (!sb_has_quota_active(sb, type)) {
+ err = -ESRCH;
+ goto out;
+ }
+ mi = sb_dqopt(sb)->info + type;
+ spin_lock(&dq_data_lock);
+ if (ii->dqi_valid & IIF_BGRACE)
+ mi->dqi_bgrace = ii->dqi_bgrace;
+ if (ii->dqi_valid & IIF_IGRACE)
+ mi->dqi_igrace = ii->dqi_igrace;
+ if (ii->dqi_valid & IIF_FLAGS)
+ mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) |
+ (ii->dqi_flags & DQF_MASK);
+ spin_unlock(&dq_data_lock);
+ mark_info_dirty(sb, type);
+ /* Force write to disk */
+ sb->dq_op->write_info(sb, type);
+out:
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+ return err;
+}
+EXPORT_SYMBOL(vfs_set_dqinfo);
+
+struct quotactl_ops vfs_quotactl_ops = {
+ .quota_on = vfs_quota_on,
+ .quota_off = vfs_quota_off,
+ .quota_sync = vfs_quota_sync,
+ .get_info = vfs_get_dqinfo,
+ .set_info = vfs_set_dqinfo,
+ .get_dqblk = vfs_get_dqblk,
+ .set_dqblk = vfs_set_dqblk
+};
+
+static ctl_table fs_dqstats_table[] = {
+ {
+ .ctl_name = FS_DQ_LOOKUPS,
+ .procname = "lookups",
+ .data = &dqstats.lookups,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_DROPS,
+ .procname = "drops",
+ .data = &dqstats.drops,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_READS,
+ .procname = "reads",
+ .data = &dqstats.reads,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_WRITES,
+ .procname = "writes",
+ .data = &dqstats.writes,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_CACHE_HITS,
+ .procname = "cache_hits",
+ .data = &dqstats.cache_hits,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_ALLOCATED,
+ .procname = "allocated_dquots",
+ .data = &dqstats.allocated_dquots,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_FREE,
+ .procname = "free_dquots",
+ .data = &dqstats.free_dquots,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = FS_DQ_SYNCS,
+ .procname = "syncs",
+ .data = &dqstats.syncs,
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+ {
+ .ctl_name = FS_DQ_WARNINGS,
+ .procname = "warnings",
+ .data = &flag_print_warnings,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+#endif
+ { .ctl_name = 0 },
+};
+
+static ctl_table fs_table[] = {
+ {
+ .ctl_name = FS_DQSTATS,
+ .procname = "quota",
+ .mode = 0555,
+ .child = fs_dqstats_table,
+ },
+ { .ctl_name = 0 },
+};
+
+static ctl_table sys_table[] = {
+ {
+ .ctl_name = CTL_FS,
+ .procname = "fs",
+ .mode = 0555,
+ .child = fs_table,
+ },
+ { .ctl_name = 0 },
+};
+
+static int __init dquot_init(void)
+{
+ int i;
+ unsigned long nr_hash, order;
+
+ printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
+
+ register_sysctl_table(sys_table);
+
+ dquot_cachep = kmem_cache_create("dquot",
+ sizeof(struct dquot), sizeof(unsigned long) * 4,
+ (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD|SLAB_PANIC),
+ NULL);
+
+ order = 0;
+ dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
+ if (!dquot_hash)
+ panic("Cannot create dquot hash table");
+
+ /* Find power-of-two hlist_heads which can fit into allocation */
+ nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
+ dq_hash_bits = 0;
+ do {
+ dq_hash_bits++;
+ } while (nr_hash >> dq_hash_bits);
+ dq_hash_bits--;
+
+ nr_hash = 1UL << dq_hash_bits;
+ dq_hash_mask = nr_hash - 1;
+ for (i = 0; i < nr_hash; i++)
+ INIT_HLIST_HEAD(dquot_hash + i);
+
+ printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
+ nr_hash, order, (PAGE_SIZE << order));
+
+ register_shrinker(&dqcache_shrinker);
+
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+ if (genl_register_family(&quota_genl_family) != 0)
+ printk(KERN_ERR
+ "VFS: Failed to create quota netlink interface.\n");
+#endif
+
+ return 0;
+}
+module_init(dquot_init);