diff options
Diffstat (limited to 'fs/fuse')
-rw-r--r-- | fs/fuse/dev.c | 279 | ||||
-rw-r--r-- | fs/fuse/dir.c | 118 | ||||
-rw-r--r-- | fs/fuse/file.c | 66 | ||||
-rw-r--r-- | fs/fuse/fuse_i.h | 64 | ||||
-rw-r--r-- | fs/fuse/inode.c | 138 |
5 files changed, 312 insertions, 353 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 23d1f52eb1b..104a62dadb9 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1,6 +1,6 @@ /* FUSE: Filesystem in Userspace - Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu> + Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu> This program can be distributed under the terms of the GNU GPL. See the file COPYING. @@ -23,13 +23,11 @@ static kmem_cache_t *fuse_req_cachep; static struct fuse_conn *fuse_get_conn(struct file *file) { - struct fuse_conn *fc; - spin_lock(&fuse_lock); - fc = file->private_data; - if (fc && !fc->connected) - fc = NULL; - spin_unlock(&fuse_lock); - return fc; + /* + * Lockless access is OK, because file->private data is set + * once during mount and is valid until the file is released. + */ + return file->private_data; } static void fuse_request_init(struct fuse_req *req) @@ -74,10 +72,8 @@ static void restore_sigs(sigset_t *oldset) */ void fuse_reset_request(struct fuse_req *req) { - int preallocated = req->preallocated; BUG_ON(atomic_read(&req->count) != 1); fuse_request_init(req); - req->preallocated = preallocated; } static void __fuse_get_request(struct fuse_req *req) @@ -92,80 +88,64 @@ static void __fuse_put_request(struct fuse_req *req) atomic_dec(&req->count); } -static struct fuse_req *do_get_request(struct fuse_conn *fc) +struct fuse_req *fuse_get_req(struct fuse_conn *fc) { struct fuse_req *req; - - spin_lock(&fuse_lock); - BUG_ON(list_empty(&fc->unused_list)); - req = list_entry(fc->unused_list.next, struct fuse_req, list); - list_del_init(&req->list); - spin_unlock(&fuse_lock); - fuse_request_init(req); - req->preallocated = 1; - req->in.h.uid = current->fsuid; - req->in.h.gid = current->fsgid; - req->in.h.pid = current->pid; - return req; -} - -/* This can return NULL, but only in case it's interrupted by a SIGKILL */ -struct fuse_req *fuse_get_request(struct fuse_conn *fc) -{ - int intr; sigset_t oldset; + int intr; + int err; atomic_inc(&fc->num_waiting); block_sigs(&oldset); - intr = down_interruptible(&fc->outstanding_sem); + intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked); restore_sigs(&oldset); - if (intr) { - atomic_dec(&fc->num_waiting); - return NULL; - } - return do_get_request(fc); -} + err = -EINTR; + if (intr) + goto out; -/* Must be called with fuse_lock held */ -static void fuse_putback_request(struct fuse_conn *fc, struct fuse_req *req) -{ - if (req->preallocated) { - atomic_dec(&fc->num_waiting); - list_add(&req->list, &fc->unused_list); - } else - fuse_request_free(req); + req = fuse_request_alloc(); + err = -ENOMEM; + if (!req) + goto out; - /* If we are in debt decrease that first */ - if (fc->outstanding_debt) - fc->outstanding_debt--; - else - up(&fc->outstanding_sem); + req->in.h.uid = current->fsuid; + req->in.h.gid = current->fsgid; + req->in.h.pid = current->pid; + req->waiting = 1; + return req; + + out: + atomic_dec(&fc->num_waiting); + return ERR_PTR(err); } void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) { if (atomic_dec_and_test(&req->count)) { - spin_lock(&fuse_lock); - fuse_putback_request(fc, req); - spin_unlock(&fuse_lock); + if (req->waiting) + atomic_dec(&fc->num_waiting); + fuse_request_free(req); } } -static void fuse_put_request_locked(struct fuse_conn *fc, struct fuse_req *req) -{ - if (atomic_dec_and_test(&req->count)) - fuse_putback_request(fc, req); -} - -void fuse_release_background(struct fuse_req *req) +/* + * Called with sbput_sem held for read (request_end) or write + * (fuse_put_super). By the time fuse_put_super() is finished, all + * inodes belonging to background requests must be released, so the + * iputs have to be done within the locked region. + */ +void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req) { iput(req->inode); iput(req->inode2); - if (req->file) - fput(req->file); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); list_del(&req->bg_entry); - spin_unlock(&fuse_lock); + if (fc->num_background == FUSE_MAX_BACKGROUND) { + fc->blocked = 0; + wake_up_all(&fc->blocked_waitq); + } + fc->num_background--; + spin_unlock(&fc->lock); } /* @@ -184,24 +164,29 @@ void fuse_release_background(struct fuse_req *req) * interrupted and put in the background, it will return with an error * and hence never be reset and reused. * - * Called with fuse_lock, unlocks it + * Called with fc->lock, unlocks it */ static void request_end(struct fuse_conn *fc, struct fuse_req *req) { list_del(&req->list); req->state = FUSE_REQ_FINISHED; if (!req->background) { + spin_unlock(&fc->lock); wake_up(&req->waitq); - fuse_put_request_locked(fc, req); - spin_unlock(&fuse_lock); + fuse_put_request(fc, req); } else { void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; req->end = NULL; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); down_read(&fc->sbput_sem); if (fc->mounted) - fuse_release_background(req); + fuse_release_background(fc, req); up_read(&fc->sbput_sem); + + /* fput must go outside sbput_sem, otherwise it can deadlock */ + if (req->file) + fput(req->file); + if (end) end(fc, req); else @@ -242,6 +227,9 @@ static void background_request(struct fuse_conn *fc, struct fuse_req *req) { req->background = 1; list_add(&req->bg_entry, &fc->background); + fc->num_background++; + if (fc->num_background == FUSE_MAX_BACKGROUND) + fc->blocked = 1; if (req->inode) req->inode = igrab(req->inode); if (req->inode2) @@ -250,16 +238,16 @@ static void background_request(struct fuse_conn *fc, struct fuse_req *req) get_file(req->file); } -/* Called with fuse_lock held. Releases, and then reacquires it. */ +/* Called with fc->lock held. Releases, and then reacquires it. */ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) { sigset_t oldset; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); block_sigs(&oldset); wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED); restore_sigs(&oldset); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); if (req->state == FUSE_REQ_FINISHED && !req->interrupted) return; @@ -273,9 +261,9 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) locked state, there mustn't be any filesystem operation (e.g. page fault), since that could lead to deadlock */ - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); wait_event(req->waitq, !req->locked); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); } if (req->state == FUSE_REQ_PENDING) { list_del(&req->list); @@ -304,19 +292,14 @@ static void queue_request(struct fuse_conn *fc, struct fuse_req *req) req->in.h.unique = fc->reqctr; req->in.h.len = sizeof(struct fuse_in_header) + len_args(req->in.numargs, (struct fuse_arg *) req->in.args); - if (!req->preallocated) { - /* If request is not preallocated (either FORGET or - RELEASE), then still decrease outstanding_sem, so - user can't open infinite number of files while not - processing the RELEASE requests. However for - efficiency do it without blocking, so if down() - would block, just increase the debt instead */ - if (down_trylock(&fc->outstanding_sem)) - fc->outstanding_debt++; - } list_add_tail(&req->list, &fc->pending); req->state = FUSE_REQ_PENDING; + if (!req->waiting) { + req->waiting = 1; + atomic_inc(&fc->num_waiting); + } wake_up(&fc->waitq); + kill_fasync(&fc->fasync, SIGIO, POLL_IN); } /* @@ -325,7 +308,7 @@ static void queue_request(struct fuse_conn *fc, struct fuse_req *req) void request_send(struct fuse_conn *fc, struct fuse_req *req) { req->isreply = 1; - spin_lock(&fuse_lock); + spin_lock(&fc->lock); if (!fc->connected) req->out.h.error = -ENOTCONN; else if (fc->conn_error) @@ -338,15 +321,16 @@ void request_send(struct fuse_conn *fc, struct fuse_req *req) request_wait_answer(fc, req); } - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req) { - spin_lock(&fuse_lock); + spin_lock(&fc->lock); + background_request(fc, req); if (fc->connected) { queue_request(fc, req); - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } else { req->out.h.error = -ENOTCONN; request_end(fc, req); @@ -362,9 +346,6 @@ void request_send_noreply(struct fuse_conn *fc, struct fuse_req *req) void request_send_background(struct fuse_conn *fc, struct fuse_req *req) { req->isreply = 1; - spin_lock(&fuse_lock); - background_request(fc, req); - spin_unlock(&fuse_lock); request_send_nowait(fc, req); } @@ -373,16 +354,16 @@ void request_send_background(struct fuse_conn *fc, struct fuse_req *req) * anything that could cause a page-fault. If the request was already * interrupted bail out. */ -static int lock_request(struct fuse_req *req) +static int lock_request(struct fuse_conn *fc, struct fuse_req *req) { int err = 0; if (req) { - spin_lock(&fuse_lock); + spin_lock(&fc->lock); if (req->interrupted) err = -ENOENT; else req->locked = 1; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } return err; } @@ -392,18 +373,19 @@ static int lock_request(struct fuse_req *req) * requester thread is currently waiting for it to be unlocked, so * wake it up. */ -static void unlock_request(struct fuse_req *req) +static void unlock_request(struct fuse_conn *fc, struct fuse_req *req) { if (req) { - spin_lock(&fuse_lock); + spin_lock(&fc->lock); req->locked = 0; if (req->interrupted) wake_up(&req->waitq); - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } } struct fuse_copy_state { + struct fuse_conn *fc; int write; struct fuse_req *req; const struct iovec *iov; @@ -416,11 +398,12 @@ struct fuse_copy_state { unsigned len; }; -static void fuse_copy_init(struct fuse_copy_state *cs, int write, - struct fuse_req *req, const struct iovec *iov, - unsigned long nr_segs) +static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc, + int write, struct fuse_req *req, + const struct iovec *iov, unsigned long nr_segs) { memset(cs, 0, sizeof(*cs)); + cs->fc = fc; cs->write = write; cs->req = req; cs->iov = iov; @@ -450,7 +433,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) unsigned long offset; int err; - unlock_request(cs->req); + unlock_request(cs->fc, cs->req); fuse_copy_finish(cs); if (!cs->seglen) { BUG_ON(!cs->nr_segs); @@ -473,7 +456,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) cs->seglen -= cs->len; cs->addr += cs->len; - return lock_request(cs->req); + return lock_request(cs->fc, cs->req); } /* Do as much copy to/from userspace buffer as we can */ @@ -585,9 +568,9 @@ static void request_wait(struct fuse_conn *fc) if (signal_pending(current)) break; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); schedule(); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); } set_current_state(TASK_RUNNING); remove_wait_queue(&fc->waitq, &wait); @@ -606,18 +589,21 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, unsigned long nr_segs, loff_t *off) { int err; - struct fuse_conn *fc; struct fuse_req *req; struct fuse_in *in; struct fuse_copy_state cs; unsigned reqsize; + struct fuse_conn *fc = fuse_get_conn(file); + if (!fc) + return -EPERM; restart: - spin_lock(&fuse_lock); - fc = file->private_data; - err = -EPERM; - if (!fc) + spin_lock(&fc->lock); + err = -EAGAIN; + if ((file->f_flags & O_NONBLOCK) && fc->connected && + list_empty(&fc->pending)) goto err_unlock; + request_wait(fc); err = -ENODEV; if (!fc->connected) @@ -641,14 +627,14 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, request_end(fc, req); goto restart; } - spin_unlock(&fuse_lock); - fuse_copy_init(&cs, 1, req, iov, nr_segs); + spin_unlock(&fc->lock); + fuse_copy_init(&cs, fc, 1, req, iov, nr_segs); err = fuse_copy_one(&cs, &in->h, sizeof(in->h)); if (!err) err = fuse_copy_args(&cs, in->numargs, in->argpages, (struct fuse_arg *) in->args, 0); fuse_copy_finish(&cs); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); req->locked = 0; if (!err && req->interrupted) err = -ENOENT; @@ -663,12 +649,12 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, else { req->state = FUSE_REQ_SENT; list_move_tail(&req->list, &fc->processing); - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } return reqsize; err_unlock: - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); return err; } @@ -735,9 +721,9 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, struct fuse_copy_state cs; struct fuse_conn *fc = fuse_get_conn(file); if (!fc) - return -ENODEV; + return -EPERM; - fuse_copy_init(&cs, 0, NULL, iov, nr_segs); + fuse_copy_init(&cs, fc, 0, NULL, iov, nr_segs); if (nbytes < sizeof(struct fuse_out_header)) return -EINVAL; @@ -749,7 +735,7 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, oh.len != nbytes) goto err_finish; - spin_lock(&fuse_lock); + spin_lock(&fc->lock); err = -ENOENT; if (!fc->connected) goto err_unlock; @@ -760,9 +746,9 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, goto err_unlock; if (req->interrupted) { - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); fuse_copy_finish(&cs); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); request_end(fc, req); return -ENOENT; } @@ -770,12 +756,12 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, req->out.h = oh; req->locked = 1; cs.req = req; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); err = copy_out_args(&cs, &req->out, nbytes); fuse_copy_finish(&cs); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); req->locked = 0; if (!err) { if (req->interrupted) @@ -787,7 +773,7 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, return err ? err : nbytes; err_unlock: - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); err_finish: fuse_copy_finish(&cs); return err; @@ -804,18 +790,19 @@ static ssize_t fuse_dev_write(struct file *file, const char __user *buf, static unsigned fuse_dev_poll(struct file *file, poll_table *wait) { - struct fuse_conn *fc = fuse_get_conn(file); unsigned mask = POLLOUT | POLLWRNORM; - + struct fuse_conn *fc = fuse_get_conn(file); if (!fc) - return -ENODEV; + return POLLERR; poll_wait(file, &fc->waitq, wait); - spin_lock(&fuse_lock); - if (!list_empty(&fc->pending)) - mask |= POLLIN | POLLRDNORM; - spin_unlock(&fuse_lock); + spin_lock(&fc->lock); + if (!fc->connected) + mask = POLLERR; + else if (!list_empty(&fc->pending)) + mask |= POLLIN | POLLRDNORM; + spin_unlock(&fc->lock); return mask; } @@ -823,7 +810,7 @@ static unsigned fuse_dev_poll(struct file *file, poll_table *wait) /* * Abort all requests on the given list (pending or processing) * - * This function releases and reacquires fuse_lock + * This function releases and reacquires fc->lock */ static void end_requests(struct fuse_conn *fc, struct list_head *head) { @@ -832,7 +819,7 @@ static void end_requests(struct fuse_conn *fc, struct list_head *head) req = list_entry(head->next, struct fuse_req, list); req->out.h.error = -ECONNABORTED; request_end(fc, req); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); } } @@ -863,10 +850,10 @@ static void end_io_requests(struct fuse_conn *fc) req->end = NULL; /* The end function will consume this reference */ __fuse_get_request(req); - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); wait_event(req->waitq, !req->locked); end(fc, req); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); } } } @@ -893,35 +880,44 @@ static void end_io_requests(struct fuse_conn *fc) */ void fuse_abort_conn(struct fuse_conn *fc) { - spin_lock(&fuse_lock); + spin_lock(&fc->lock); if (fc->connected) { fc->connected = 0; end_io_requests(fc); end_requests(fc, &fc->pending); end_requests(fc, &fc->processing); wake_up_all(&fc->waitq); + kill_fasync(&fc->fasync, SIGIO, POLL_IN); } - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); } static int fuse_dev_release(struct inode *inode, struct file *file) { - struct fuse_conn *fc; - - spin_lock(&fuse_lock); - fc = file->private_data; + struct fuse_conn *fc = fuse_get_conn(file); if (fc) { + spin_lock(&fc->lock); fc->connected = 0; end_requests(fc, &fc->pending); end_requests(fc, &fc->processing); - } - spin_unlock(&fuse_lock); - if (fc) + spin_unlock(&fc->lock); + fasync_helper(-1, file, 0, &fc->fasync); kobject_put(&fc->kobj); + } return 0; } +static int fuse_dev_fasync(int fd, struct file *file, int on) +{ + struct fuse_conn *fc = fuse_get_conn(file); + if (!fc) + return -EPERM; + + /* No locking - fasync_helper does its own locking */ + return fasync_helper(fd, file, on, &fc->fasync); +} + const struct file_operations fuse_dev_operations = { .owner = THIS_MODULE, .llseek = no_llseek, @@ -931,6 +927,7 @@ const struct file_operations fuse_dev_operations = { .writev = fuse_dev_writev, .poll = fuse_dev_poll, .release = fuse_dev_release, + .fasync = fuse_dev_fasync, }; static struct miscdevice fuse_miscdevice = { diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 256355b8025..8d7546e832e 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -117,8 +117,8 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) return 0; fc = get_fuse_conn(inode); - req = fuse_get_request(fc); - if (!req) + req = fuse_get_req(fc); + if (IS_ERR(req)) return 0; fuse_lookup_init(req, entry->d_parent->d_inode, entry, &outarg); @@ -188,9 +188,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, if (entry->d_name.len > FUSE_NAME_MAX) return ERR_PTR(-ENAMETOOLONG); - req = fuse_get_request(fc); - if (!req) - return ERR_PTR(-EINTR); + req = fuse_get_req(fc); + if (IS_ERR(req)) + return ERR_PTR(PTR_ERR(req)); fuse_lookup_init(req, dir, entry, &outarg); request_send(fc, req); @@ -244,15 +244,14 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, struct file *file; int flags = nd->intent.open.flags - 1; - err = -ENOSYS; if (fc->no_create) - goto out; + return -ENOSYS; - err = -EINTR; - req = fuse_get_request(fc); - if (!req) - goto out; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); + err = -ENOMEM; ff = fuse_file_alloc(); if (!ff) goto out_put_request; @@ -314,7 +313,6 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, fuse_file_free(ff); out_put_request: fuse_put_request(fc, req); - out: return err; } @@ -375,9 +373,9 @@ static int fuse_mknod(struct inode *dir, struct dentry *entry, int mode, { struct fuse_mknod_in inarg; struct fuse_conn *fc = get_fuse_conn(dir); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.mode = mode; @@ -407,9 +405,9 @@ static int fuse_mkdir(struct inode *dir, struct dentry *entry, int mode) { struct fuse_mkdir_in inarg; struct fuse_conn *fc = get_fuse_conn(dir); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.mode = mode; @@ -427,9 +425,9 @@ static int fuse_symlink(struct inode *dir, struct dentry *entry, { struct fuse_conn *fc = get_fuse_conn(dir); unsigned len = strlen(link) + 1; - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->in.h.opcode = FUSE_SYMLINK; req->in.numargs = 2; @@ -444,9 +442,9 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry) { int err; struct fuse_conn *fc = get_fuse_conn(dir); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->in.h.opcode = FUSE_UNLINK; req->in.h.nodeid = get_node_id(dir); @@ -476,9 +474,9 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry) { int err; struct fuse_conn *fc = get_fuse_conn(dir); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->in.h.opcode = FUSE_RMDIR; req->in.h.nodeid = get_node_id(dir); @@ -504,9 +502,9 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent, int err; struct fuse_rename_in inarg; struct fuse_conn *fc = get_fuse_conn(olddir); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.newdir = get_node_id(newdir); @@ -553,9 +551,9 @@ static int fuse_link(struct dentry *entry, struct inode *newdir, struct fuse_link_in inarg; struct inode *inode = entry->d_inode; struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.oldnodeid = get_node_id(inode); @@ -583,9 +581,9 @@ int fuse_do_getattr(struct inode *inode) int err; struct fuse_attr_out arg; struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_req *req = fuse_get_request(fc); - if (!req) - return -EINTR; + struct fuse_req *req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->in.h.opcode = FUSE_GETATTR; req->in.h.nodeid = get_node_id(inode); @@ -673,9 +671,9 @@ static int fuse_access(struct inode *inode, int mask) if (fc->no_access) return 0; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.mask = mask; @@ -780,9 +778,9 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir) if (is_bad_inode(inode)) return -EIO; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); page = alloc_page(GFP_KERNEL); if (!page) { @@ -809,11 +807,11 @@ static char *read_link(struct dentry *dentry) { struct inode *inode = dentry->d_inode; struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_req *req = fuse_get_request(fc); + struct fuse_req *req = fuse_get_req(fc); char *link; - if (!req) - return ERR_PTR(-EINTR); + if (IS_ERR(req)) + return ERR_PTR(PTR_ERR(req)); link = (char *) __get_free_page(GFP_KERNEL); if (!link) { @@ -933,9 +931,9 @@ static int fuse_setattr(struct dentry *entry, struct iattr *attr) } } - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); iattr_to_fattr(attr, &inarg); @@ -995,9 +993,9 @@ static int fuse_setxattr(struct dentry *entry, const char *name, if (fc->no_setxattr) return -EOPNOTSUPP; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.size = size; @@ -1035,9 +1033,9 @@ static ssize_t fuse_getxattr(struct dentry *entry, const char *name, if (fc->no_getxattr) return -EOPNOTSUPP; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.size = size; @@ -1085,9 +1083,9 @@ static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) if (fc->no_listxattr) return -EOPNOTSUPP; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.size = size; @@ -1131,9 +1129,9 @@ static int fuse_removexattr(struct dentry *entry, const char *name) if (fc->no_removexattr) return -EOPNOTSUPP; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->in.h.opcode = FUSE_REMOVEXATTR; req->in.h.nodeid = get_node_id(inode); diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 975f2697e86..fc342cf7c2c 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1,6 +1,6 @@ /* FUSE: Filesystem in Userspace - Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu> + Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu> This program can be distributed under the terms of the GNU GPL. See the file COPYING. @@ -22,9 +22,9 @@ static int fuse_send_open(struct inode *inode, struct file *file, int isdir, struct fuse_req *req; int err; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); @@ -184,9 +184,9 @@ static int fuse_flush(struct file *file) if (fc->no_flush) return 0; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; @@ -223,9 +223,9 @@ int fuse_fsync_common(struct file *file, struct dentry *de, int datasync, if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir)) return 0; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; @@ -297,9 +297,9 @@ static int fuse_readpage(struct file *file, struct page *page) if (is_bad_inode(inode)) goto out; - err = -EINTR; - req = fuse_get_request(fc); - if (!req) + req = fuse_get_req(fc); + err = PTR_ERR(req); + if (IS_ERR(req)) goto out; req->out.page_zeroing = 1; @@ -368,10 +368,10 @@ static int fuse_readpages_fill(void *_data, struct page *page) (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read || req->pages[req->num_pages - 1]->index + 1 != page->index)) { fuse_send_readpages(req, data->file, inode); - data->req = req = fuse_get_request(fc); - if (!req) { + data->req = req = fuse_get_req(fc); + if (IS_ERR(req)) { unlock_page(page); - return -EINTR; + return PTR_ERR(req); } } req->pages[req->num_pages] = page; @@ -392,13 +392,17 @@ static int fuse_readpages(struct file *file, struct address_space *mapping, data.file = file; data.inode = inode; - data.req = fuse_get_request(fc); - if (!data.req) - return -EINTR; + data.req = fuse_get_req(fc); + if (IS_ERR(data.req)) + return PTR_ERR(data.req); err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data); - if (!err) - fuse_send_readpages(data.req, file, inode); + if (!err) { + if (data.req->num_pages) + fuse_send_readpages(data.req, file, inode); + else + fuse_put_request(fc, data.req); + } return err; } @@ -451,9 +455,9 @@ static int fuse_commit_write(struct file *file, struct page *page, if (is_bad_inode(inode)) return -EIO; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); req->num_pages = 1; req->pages[0] = page; @@ -528,9 +532,9 @@ static ssize_t fuse_direct_io(struct file *file, const char __user *buf, if (is_bad_inode(inode)) return -EIO; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); while (count) { size_t nres; @@ -561,8 +565,12 @@ static ssize_t fuse_direct_io(struct file *file, const char __user *buf, buf += nres; if (nres != nbytes) break; - if (count) - fuse_reset_request(req); + if (count) { + fuse_put_request(fc, req); + req = fuse_get_req(fc); + if (IS_ERR(req)) + break; + } } fuse_put_request(fc, req); if (res > 0) { diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index a16a04fcf41..0474202cb5d 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -1,6 +1,6 @@ /* FUSE: Filesystem in Userspace - Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu> + Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu> This program can be distributed under the terms of the GNU GPL. See the file COPYING. @@ -18,8 +18,8 @@ /** Max number of pages that can be used in a single read request */ #define FUSE_MAX_PAGES_PER_REQ 32 -/** If more requests are outstanding, then the operation will block */ -#define FUSE_MAX_OUTSTANDING 10 +/** Maximum number of outstanding background requests */ +#define FUSE_MAX_BACKGROUND 10 /** It could be as large as PATH_MAX, but would that have any uses? */ #define FUSE_NAME_MAX 1024 @@ -131,8 +131,8 @@ struct fuse_conn; * A request to the client */ struct fuse_req { - /** This can be on either unused_list, pending processing or - io lists in fuse_conn */ + /** This can be on either pending processing or io lists in + fuse_conn */ struct list_head list; /** Entry on the background list */ @@ -144,15 +144,12 @@ struct fuse_req { /* * The following bitfields are either set once before the * request is queued or setting/clearing them is protected by - * fuse_lock + * fuse_conn->lock */ /** True if the request has reply */ unsigned isreply:1; - /** The request is preallocated */ - unsigned preallocated:1; - /** The request was interrupted */ unsigned interrupted:1; @@ -162,6 +159,9 @@ struct fuse_req { /** Data is being copied to/from the request */ unsigned locked:1; + /** Request is counted as "waiting" */ + unsigned waiting:1; + /** State of the request */ enum fuse_req_state state; @@ -213,6 +213,9 @@ struct fuse_req { * unmounted. */ struct fuse_conn { + /** Lock protecting accessess to members of this structure */ + spinlock_t lock; + /** The user id for this mount */ uid_t user_id; @@ -244,19 +247,20 @@ struct fuse_conn { interrupted request) */ struct list_head background; - /** Controls the maximum number of outstanding requests */ - struct semaphore outstanding_sem; + /** Number of requests currently in the background */ + unsigned num_background; - /** This counts the number of outstanding requests if - outstanding_sem would go negative */ - unsigned outstanding_debt; + /** Flag indicating if connection is blocked. This will be + the case before the INIT reply is received, and if there + are too many outstading backgrounds requests */ + int blocked; + + /** waitq for blocked connection */ + wait_queue_head_t blocked_waitq; /** RW semaphore for exclusion with fuse_put_super() */ struct rw_semaphore sbput_sem; - /** The list of unused requests */ - struct list_head unused_list; - /** The next unique request id */ u64 reqctr; @@ -318,6 +322,9 @@ struct fuse_conn { /** kobject */ struct kobject kobj; + + /** O_ASYNC requests */ + struct fasync_struct *fasync; }; static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb) @@ -349,21 +356,6 @@ static inline u64 get_node_id(struct inode *inode) extern const struct file_operations fuse_dev_operations; /** - * This is the single global spinlock which protects FUSE's structures - * - * The following data is protected by this lock: - * - * - the private_data field of the device file - * - the s_fs_info field of the super block - * - unused_list, pending, processing lists in fuse_conn - * - background list in fuse_conn - * - the unique request ID counter reqctr in fuse_conn - * - the sb (super_block) field in fuse_conn - * - the file (device file) field in fuse_conn - */ -extern spinlock_t fuse_lock; - -/** * Get a filled in inode */ struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid, @@ -461,11 +453,11 @@ void fuse_reset_request(struct fuse_req *req); /** * Reserve a preallocated request */ -struct fuse_req *fuse_get_request(struct fuse_conn *fc); +struct fuse_req *fuse_get_req(struct fuse_conn *fc); /** - * Decrement reference count of a request. If count goes to zero put - * on unused list (preallocated) or free request (not preallocated). + * Decrement reference count of a request. If count goes to zero free + * the request. */ void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req); @@ -487,7 +479,7 @@ void request_send_background(struct fuse_conn *fc, struct fuse_req *req); /** * Release inodes and file associated with background request */ -void fuse_release_background(struct fuse_req *req); +void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req); /* Abort all requests */ void fuse_abort_conn(struct fuse_conn *fc); diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 879e6fba948..7627022446b 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1,6 +1,6 @@ /* FUSE: Filesystem in Userspace - Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu> + Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu> This program can be distributed under the terms of the GNU GPL. See the file COPYING. @@ -22,7 +22,6 @@ MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); MODULE_DESCRIPTION("Filesystem in Userspace"); MODULE_LICENSE("GPL"); -spinlock_t fuse_lock; static kmem_cache_t *fuse_inode_cachep; static struct subsystem connections_subsys; @@ -207,15 +206,17 @@ static void fuse_put_super(struct super_block *sb) down_write(&fc->sbput_sem); while (!list_empty(&fc->background)) - fuse_release_background(list_entry(fc->background.next, + fuse_release_background(fc, + list_entry(fc->background.next, struct fuse_req, bg_entry)); - spin_lock(&fuse_lock); + spin_lock(&fc->lock); fc->mounted = 0; fc->connected = 0; - spin_unlock(&fuse_lock); + spin_unlock(&fc->lock); up_write(&fc->sbput_sem); /* Flush all readers on this fs */ + kill_fasync(&fc->fasync, SIGIO, POLL_IN); wake_up_all(&fc->waitq); kobject_del(&fc->kobj); kobject_put(&fc->kobj); @@ -242,9 +243,9 @@ static int fuse_statfs(struct super_block *sb, struct kstatfs *buf) struct fuse_statfs_out outarg; int err; - req = fuse_get_request(fc); - if (!req) - return -EINTR; + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); memset(&outarg, 0, sizeof(outarg)); req->in.numargs = 0; @@ -369,15 +370,7 @@ static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt) static void fuse_conn_release(struct kobject *kobj) { - struct fuse_conn *fc = get_fuse_conn_kobj(kobj); - - while (!list_empty(&fc->unused_list)) { - struct fuse_req *req; - req = list_entry(fc->unused_list.next, struct fuse_req, list); - list_del(&req->list); - fuse_request_free(req); - } - kfree(fc); + kfree(get_fuse_conn_kobj(kobj)); } static struct fuse_conn *new_conn(void) @@ -386,64 +379,25 @@ static struct fuse_conn *new_conn(void) fc = kzalloc(sizeof(*fc), GFP_KERNEL); if (fc) { - int i; + spin_lock_init(&fc->lock); init_waitqueue_head(&fc->waitq); + init_waitqueue_head(&fc->blocked_waitq); INIT_LIST_HEAD(&fc->pending); INIT_LIST_HEAD(&fc->processing); INIT_LIST_HEAD(&fc->io); - INIT_LIST_HEAD(&fc->unused_list); INIT_LIST_HEAD(&fc->background); - sema_init(&fc->outstanding_sem, 1); /* One for INIT */ init_rwsem(&fc->sbput_sem); kobj_set_kset_s(fc, connections_subsys); kobject_init(&fc->kobj); atomic_set(&fc->num_waiting, 0); - for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) { - struct fuse_req *req = fuse_request_alloc(); - if (!req) { - kobject_put(&fc->kobj); - return NULL; - } - list_add(&req->list, &fc->unused_list); - } fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE; fc->bdi.unplug_io_fn = default_unplug_io_fn; fc->reqctr = 0; + fc->blocked = 1; } return fc; } -static struct fuse_conn *get_conn(struct file *file, struct super_block *sb) -{ - struct fuse_conn *fc; - int err; - - err = -EINVAL; - if (file->f_op != &fuse_dev_operations) - goto out_err; - - err = -ENOMEM; - fc = new_conn(); - if (!fc) - goto out_err; - - spin_lock(&fuse_lock); - err = -EINVAL; - if (file->private_data) - goto out_unlock; - - kobject_get(&fc->kobj); - file->private_data = fc; - spin_unlock(&fuse_lock); - return fc; - - out_unlock: - spin_unlock(&fuse_lock); - kobject_put(&fc->kobj); - out_err: - return ERR_PTR(err); -} - static struct inode *get_root_inode(struct super_block *sb, unsigned mode) { struct fuse_attr attr; @@ -467,7 +421,6 @@ static struct super_operations fuse_super_operations = { static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) { - int i; struct fuse_init_out *arg = &req->misc.init_out; if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION) @@ -486,22 +439,13 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) fc->minor = arg->minor; fc->max_write = arg->minor < 5 ? 4096 : arg->max_write; } - - /* After INIT reply is received other requests can go - out. So do (FUSE_MAX_OUTSTANDING - 1) number of - up()s on outstanding_sem. The last up() is done in - fuse_putback_request() */ - for (i = 1; i < FUSE_MAX_OUTSTANDING; i++) - up(&fc->outstanding_sem); - fuse_put_request(fc, req); + fc->blocked = 0; + wake_up_all(&fc->blocked_waitq); } -static void fuse_send_init(struct fuse_conn *fc) +static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) { - /* This is called from fuse_read_super() so there's guaranteed - to be exactly one request available */ - struct fuse_req *req = fuse_get_request(fc); struct fuse_init_in *arg = &req->misc.init_in; arg->major = FUSE_KERNEL_VERSION; @@ -525,12 +469,9 @@ static void fuse_send_init(struct fuse_conn *fc) static unsigned long long conn_id(void) { + /* BKL is held for ->get_sb() */ static unsigned long long ctr = 1; - unsigned long long val; - spin_lock(&fuse_lock); - val = ctr++; - spin_unlock(&fuse_lock); - return val; + return ctr++; } static int fuse_fill_super(struct super_block *sb, void *data, int silent) @@ -540,6 +481,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) struct fuse_mount_data d; struct file *file; struct dentry *root_dentry; + struct fuse_req *init_req; int err; if (!parse_fuse_opt((char *) data, &d)) @@ -555,10 +497,12 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) if (!file) return -EINVAL; - fc = get_conn(file, sb); - fput(file); - if (IS_ERR(fc)) - return PTR_ERR(fc); + if (file->f_op != &fuse_dev_operations) + return -EINVAL; + + fc = new_conn(); + if (!fc) + return -ENOMEM; fc->flags = d.flags; fc->user_id = d.user_id; @@ -579,27 +523,48 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) goto err; } + init_req = fuse_request_alloc(); + if (!init_req) + goto err_put_root; + err = kobject_set_name(&fc->kobj, "%llu", conn_id()); if (err) - goto err_put_root; + goto err_free_req; err = kobject_add(&fc->kobj); if (err) - goto err_put_root; + goto err_free_req; + + /* Setting file->private_data can't race with other mount() + instances, since BKL is held for ->get_sb() */ + err = -EINVAL; + if (file->private_data) + goto err_kobject_del; sb->s_root = root_dentry; - spin_lock(&fuse_lock); fc->mounted = 1; fc->connected = 1; - spin_unlock(&fuse_lock); + kobject_get(&fc->kobj); + file->private_data = fc; + /* + * atomic_dec_and_test() in fput() provides the necessary + * memory barrier for file->private_data to be visible on all + * CPUs after this + */ + fput(file); - fuse_send_init(fc); + fuse_send_init(fc, init_req); return 0; + err_kobject_del: + kobject_del(&fc->kobj); + err_free_req: + fuse_request_free(init_req); err_put_root: dput(root_dentry); err: + fput(file); kobject_put(&fc->kobj); return err; } @@ -753,7 +718,6 @@ static int __init fuse_init(void) printk("fuse init (API version %i.%i)\n", FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); - spin_lock_init(&fuse_lock); res = fuse_fs_init(); if (res) goto err; |