diff options
| -rw-r--r-- | fs/fuse/dir.c | 216 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 10 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 3 |
3 files changed, 208 insertions, 21 deletions
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index ecaec0fea3a1..77982fdbcf27 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -27,6 +27,67 @@ module_param(allow_sys_admin_access, bool, 0644); MODULE_PARM_DESC(allow_sys_admin_access, "Allow users with CAP_SYS_ADMIN in initial userns to bypass allow_other access check"); +struct dentry_bucket { + struct rb_root tree; + spinlock_t lock; +}; + +#define HASH_BITS 5 +#define HASH_SIZE (1 << HASH_BITS) +static struct dentry_bucket dentry_hash[HASH_SIZE]; +struct delayed_work dentry_tree_work; + +/* Minimum invalidation work queue frequency */ +#define FUSE_DENTRY_INVAL_FREQ_MIN 5 + +unsigned __read_mostly inval_wq; +static int inval_wq_set(const char *val, const struct kernel_param *kp) +{ + unsigned int num; + unsigned int old = inval_wq; + int ret; + + if (!val) + return -EINVAL; + + ret = kstrtouint(val, 0, &num); + if (ret) + return ret; + + if ((num < FUSE_DENTRY_INVAL_FREQ_MIN) && (num != 0)) + return -EINVAL; + + /* This should prevent overflow in secs_to_jiffies() */ + if (num > USHRT_MAX) + return -EINVAL; + + *((unsigned int *)kp->arg) = num; + + if (num && !old) + schedule_delayed_work(&dentry_tree_work, + secs_to_jiffies(num)); + else if (!num && old) + cancel_delayed_work_sync(&dentry_tree_work); + + return 0; +} +static const struct kernel_param_ops inval_wq_ops = { + .set = inval_wq_set, + .get = param_get_uint, +}; +module_param_cb(inval_wq, &inval_wq_ops, &inval_wq, 0644); +__MODULE_PARM_TYPE(inval_wq, "uint"); +MODULE_PARM_DESC(inval_wq, + "Dentries invalidation work queue period in secs (>= " + __stringify(FUSE_DENTRY_INVAL_FREQ_MIN) ")."); + +static inline struct dentry_bucket *get_dentry_bucket(struct dentry *dentry) +{ + int i = hash_ptr(dentry, HASH_BITS); + + return &dentry_hash[i]; +} + static void fuse_advise_use_readdirplus(struct inode *dir) { struct fuse_inode *fi = get_fuse_inode(dir); @@ -34,33 +95,131 @@ static void fuse_advise_use_readdirplus(struct inode *dir) set_bit(FUSE_I_ADVISE_RDPLUS, &fi->state); } -#if BITS_PER_LONG >= 64 -static inline void __fuse_dentry_settime(struct dentry *entry, u64 time) +struct fuse_dentry { + u64 time; + union { + struct rcu_head rcu; + struct rb_node node; + }; + struct dentry *dentry; +}; + +static void __fuse_dentry_tree_del_node(struct fuse_dentry *fd, + struct dentry_bucket *bucket) { - entry->d_fsdata = (void *) time; + if (!RB_EMPTY_NODE(&fd->node)) { + rb_erase(&fd->node, &bucket->tree); + RB_CLEAR_NODE(&fd->node); + } } -static inline u64 fuse_dentry_time(const struct dentry *entry) +static void fuse_dentry_tree_del_node(struct dentry *dentry) { - return (u64)entry->d_fsdata; + struct fuse_dentry *fd = dentry->d_fsdata; + struct dentry_bucket *bucket = get_dentry_bucket(dentry); + + spin_lock(&bucket->lock); + __fuse_dentry_tree_del_node(fd, bucket); + spin_unlock(&bucket->lock); } -#else -union fuse_dentry { - u64 time; - struct rcu_head rcu; -}; +static void fuse_dentry_tree_add_node(struct dentry *dentry) +{ + struct fuse_dentry *fd = dentry->d_fsdata; + struct dentry_bucket *bucket; + struct fuse_dentry *cur; + struct rb_node **p, *parent = NULL; + + if (!inval_wq) + return; + + bucket = get_dentry_bucket(dentry); + + spin_lock(&bucket->lock); + + __fuse_dentry_tree_del_node(fd, bucket); + + p = &bucket->tree.rb_node; + while (*p) { + parent = *p; + cur = rb_entry(*p, struct fuse_dentry, node); + if (fd->time < cur->time) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + rb_link_node(&fd->node, parent, p); + rb_insert_color(&fd->node, &bucket->tree); + spin_unlock(&bucket->lock); +} + +/* + * work queue which, when enabled, will periodically check for expired dentries + * in the dentries tree. + */ +static void fuse_dentry_tree_work(struct work_struct *work) +{ + LIST_HEAD(dispose); + struct fuse_dentry *fd; + struct rb_node *node; + int i; + + for (i = 0; i < HASH_SIZE; i++) { + spin_lock(&dentry_hash[i].lock); + node = rb_first(&dentry_hash[i].tree); + while (node) { + fd = rb_entry(node, struct fuse_dentry, node); + if (time_after64(get_jiffies_64(), fd->time)) { + rb_erase(&fd->node, &dentry_hash[i].tree); + RB_CLEAR_NODE(&fd->node); + spin_unlock(&dentry_hash[i].lock); + d_dispose_if_unused(fd->dentry, &dispose); + cond_resched(); + spin_lock(&dentry_hash[i].lock); + } else + break; + node = rb_first(&dentry_hash[i].tree); + } + spin_unlock(&dentry_hash[i].lock); + shrink_dentry_list(&dispose); + } + + if (inval_wq) + schedule_delayed_work(&dentry_tree_work, + secs_to_jiffies(inval_wq)); +} + +void fuse_dentry_tree_init(void) +{ + int i; + + for (i = 0; i < HASH_SIZE; i++) { + spin_lock_init(&dentry_hash[i].lock); + dentry_hash[i].tree = RB_ROOT; + } + INIT_DELAYED_WORK(&dentry_tree_work, fuse_dentry_tree_work); +} + +void fuse_dentry_tree_cleanup(void) +{ + int i; + + inval_wq = 0; + cancel_delayed_work_sync(&dentry_tree_work); + + for (i = 0; i < HASH_SIZE; i++) + WARN_ON_ONCE(!RB_EMPTY_ROOT(&dentry_hash[i].tree)); +} static inline void __fuse_dentry_settime(struct dentry *dentry, u64 time) { - ((union fuse_dentry *) dentry->d_fsdata)->time = time; + ((struct fuse_dentry *) dentry->d_fsdata)->time = time; } static inline u64 fuse_dentry_time(const struct dentry *entry) { - return ((union fuse_dentry *) entry->d_fsdata)->time; + return ((struct fuse_dentry *) entry->d_fsdata)->time; } -#endif static void fuse_dentry_settime(struct dentry *dentry, u64 time) { @@ -81,6 +240,7 @@ static void fuse_dentry_settime(struct dentry *dentry, u64 time) } __fuse_dentry_settime(dentry, time); + fuse_dentry_tree_add_node(dentry); } /* @@ -283,21 +443,36 @@ invalid: goto out; } -#if BITS_PER_LONG < 64 static int fuse_dentry_init(struct dentry *dentry) { - dentry->d_fsdata = kzalloc(sizeof(union fuse_dentry), - GFP_KERNEL_ACCOUNT | __GFP_RECLAIMABLE); + struct fuse_dentry *fd; - return dentry->d_fsdata ? 0 : -ENOMEM; + fd = kzalloc(sizeof(struct fuse_dentry), + GFP_KERNEL_ACCOUNT | __GFP_RECLAIMABLE); + if (!fd) + return -ENOMEM; + + fd->dentry = dentry; + RB_CLEAR_NODE(&fd->node); + dentry->d_fsdata = fd; + + return 0; +} + +static void fuse_dentry_prune(struct dentry *dentry) +{ + struct fuse_dentry *fd = dentry->d_fsdata; + + if (!RB_EMPTY_NODE(&fd->node)) + fuse_dentry_tree_del_node(dentry); } + static void fuse_dentry_release(struct dentry *dentry) { - union fuse_dentry *fd = dentry->d_fsdata; + struct fuse_dentry *fd = dentry->d_fsdata; kfree_rcu(fd, rcu); } -#endif static int fuse_dentry_delete(const struct dentry *dentry) { @@ -331,10 +506,9 @@ static struct vfsmount *fuse_dentry_automount(struct path *path) const struct dentry_operations fuse_dentry_operations = { .d_revalidate = fuse_dentry_revalidate, .d_delete = fuse_dentry_delete, -#if BITS_PER_LONG < 64 .d_init = fuse_dentry_init, + .d_prune = fuse_dentry_prune, .d_release = fuse_dentry_release, -#endif .d_automount = fuse_dentry_automount, }; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index c2f2a48156d6..ac717b3b46a1 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -54,6 +54,13 @@ /** Frequency (in jiffies) of request timeout checks, if opted into */ extern const unsigned long fuse_timeout_timer_freq; +/* + * Dentries invalidation workqueue period, in seconds. The value of this + * parameter shall be >= FUSE_DENTRY_INVAL_FREQ_MIN seconds, or 0 (zero), in + * which case no workqueue will be created. + */ +extern unsigned inval_wq __read_mostly; + /** Maximum of max_pages received in init_out */ extern unsigned int fuse_max_pages_limit; /* @@ -1277,6 +1284,9 @@ void fuse_wait_aborted(struct fuse_conn *fc); /* Check if any requests timed out */ void fuse_check_timeout(struct work_struct *work); +void fuse_dentry_tree_init(void); +void fuse_dentry_tree_cleanup(void); + /** * Invalidate inode attributes */ diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index d1babf56f254..793f1766ae5a 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -2294,6 +2294,8 @@ static int __init fuse_init(void) if (res) goto err_sysfs_cleanup; + fuse_dentry_tree_init(); + sanitize_global_limit(&max_user_bgreq); sanitize_global_limit(&max_user_congthresh); @@ -2313,6 +2315,7 @@ static void __exit fuse_exit(void) { pr_debug("exit\n"); + fuse_dentry_tree_cleanup(); fuse_ctl_cleanup(); fuse_sysfs_cleanup(); fuse_fs_cleanup(); |