diff options
Diffstat (limited to 'fs/fuse')
| -rw-r--r-- | fs/fuse/Makefile | 2 | ||||
| -rw-r--r-- | fs/fuse/control.c | 218 | ||||
| -rw-r--r-- | fs/fuse/dev.c | 418 | ||||
| -rw-r--r-- | fs/fuse/dir.c | 56 | ||||
| -rw-r--r-- | fs/fuse/file.c | 206 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 135 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 178 |
7 files changed, 842 insertions, 371 deletions
diff --git a/fs/fuse/Makefile b/fs/fuse/Makefile index c3e1f760cac..72437065f6a 100644 --- a/fs/fuse/Makefile +++ b/fs/fuse/Makefile @@ -4,4 +4,4 @@ obj-$(CONFIG_FUSE_FS) += fuse.o -fuse-objs := dev.o dir.o file.o inode.o +fuse-objs := dev.o dir.o file.o inode.o control.o diff --git a/fs/fuse/control.c b/fs/fuse/control.c new file mode 100644 index 00000000000..a3bce3a7725 --- /dev/null +++ b/fs/fuse/control.c @@ -0,0 +1,218 @@ +/* + FUSE: Filesystem in Userspace + 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. +*/ + +#include "fuse_i.h" + +#include <linux/init.h> +#include <linux/module.h> + +#define FUSE_CTL_SUPER_MAGIC 0x65735543 + +/* + * This is non-NULL when the single instance of the control filesystem + * exists. Protected by fuse_mutex + */ +static struct super_block *fuse_control_sb; + +static struct fuse_conn *fuse_ctl_file_conn_get(struct file *file) +{ + struct fuse_conn *fc; + mutex_lock(&fuse_mutex); + fc = file->f_dentry->d_inode->u.generic_ip; + if (fc) + fc = fuse_conn_get(fc); + mutex_unlock(&fuse_mutex); + return fc; +} + +static ssize_t fuse_conn_abort_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct fuse_conn *fc = fuse_ctl_file_conn_get(file); + if (fc) { + fuse_abort_conn(fc); + fuse_conn_put(fc); + } + return count; +} + +static ssize_t fuse_conn_waiting_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + char tmp[32]; + size_t size; + + if (!*ppos) { + struct fuse_conn *fc = fuse_ctl_file_conn_get(file); + if (!fc) + return 0; + + file->private_data=(void *)(long)atomic_read(&fc->num_waiting); + fuse_conn_put(fc); + } + size = sprintf(tmp, "%ld\n", (long)file->private_data); + return simple_read_from_buffer(buf, len, ppos, tmp, size); +} + +static const struct file_operations fuse_ctl_abort_ops = { + .open = nonseekable_open, + .write = fuse_conn_abort_write, +}; + +static const struct file_operations fuse_ctl_waiting_ops = { + .open = nonseekable_open, + .read = fuse_conn_waiting_read, +}; + +static struct dentry *fuse_ctl_add_dentry(struct dentry *parent, + struct fuse_conn *fc, + const char *name, + int mode, int nlink, + struct inode_operations *iop, + const struct file_operations *fop) +{ + struct dentry *dentry; + struct inode *inode; + + BUG_ON(fc->ctl_ndents >= FUSE_CTL_NUM_DENTRIES); + dentry = d_alloc_name(parent, name); + if (!dentry) + return NULL; + + fc->ctl_dentry[fc->ctl_ndents++] = dentry; + inode = new_inode(fuse_control_sb); + if (!inode) + return NULL; + + inode->i_mode = mode; + inode->i_uid = fc->user_id; + inode->i_gid = fc->group_id; + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; + /* setting ->i_op to NULL is not allowed */ + if (iop) + inode->i_op = iop; + inode->i_fop = fop; + inode->i_nlink = nlink; + inode->u.generic_ip = fc; + d_add(dentry, inode); + return dentry; +} + +/* + * Add a connection to the control filesystem (if it exists). Caller + * must host fuse_mutex + */ +int fuse_ctl_add_conn(struct fuse_conn *fc) +{ + struct dentry *parent; + char name[32]; + + if (!fuse_control_sb) + return 0; + + parent = fuse_control_sb->s_root; + parent->d_inode->i_nlink++; + sprintf(name, "%llu", (unsigned long long) fc->id); + parent = fuse_ctl_add_dentry(parent, fc, name, S_IFDIR | 0500, 2, + &simple_dir_inode_operations, + &simple_dir_operations); + if (!parent) + goto err; + + if (!fuse_ctl_add_dentry(parent, fc, "waiting", S_IFREG | 0400, 1, + NULL, &fuse_ctl_waiting_ops) || + !fuse_ctl_add_dentry(parent, fc, "abort", S_IFREG | 0200, 1, + NULL, &fuse_ctl_abort_ops)) + goto err; + + return 0; + + err: + fuse_ctl_remove_conn(fc); + return -ENOMEM; +} + +/* + * Remove a connection from the control filesystem (if it exists). + * Caller must host fuse_mutex + */ +void fuse_ctl_remove_conn(struct fuse_conn *fc) +{ + int i; + + if (!fuse_control_sb) + return; + + for (i = fc->ctl_ndents - 1; i >= 0; i--) { + struct dentry *dentry = fc->ctl_dentry[i]; + dentry->d_inode->u.generic_ip = NULL; + d_drop(dentry); + dput(dentry); + } + fuse_control_sb->s_root->d_inode->i_nlink--; +} + +static int fuse_ctl_fill_super(struct super_block *sb, void *data, int silent) +{ + struct tree_descr empty_descr = {""}; + struct fuse_conn *fc; + int err; + + err = simple_fill_super(sb, FUSE_CTL_SUPER_MAGIC, &empty_descr); + if (err) + return err; + + mutex_lock(&fuse_mutex); + BUG_ON(fuse_control_sb); + fuse_control_sb = sb; + list_for_each_entry(fc, &fuse_conn_list, entry) { + err = fuse_ctl_add_conn(fc); + if (err) { + fuse_control_sb = NULL; + mutex_unlock(&fuse_mutex); + return err; + } + } + mutex_unlock(&fuse_mutex); + + return 0; +} + +static int fuse_ctl_get_sb(struct file_system_type *fs_type, int flags, + const char *dev_name, void *raw_data, + struct vfsmount *mnt) +{ + return get_sb_single(fs_type, flags, raw_data, + fuse_ctl_fill_super, mnt); +} + +static void fuse_ctl_kill_sb(struct super_block *sb) +{ + mutex_lock(&fuse_mutex); + fuse_control_sb = NULL; + mutex_unlock(&fuse_mutex); + + kill_litter_super(sb); +} + +static struct file_system_type fuse_ctl_fs_type = { + .owner = THIS_MODULE, + .name = "fusectl", + .get_sb = fuse_ctl_get_sb, + .kill_sb = fuse_ctl_kill_sb, +}; + +int __init fuse_ctl_init(void) +{ + return register_filesystem(&fuse_ctl_fs_type); +} + +void fuse_ctl_cleanup(void) +{ + unregister_filesystem(&fuse_ctl_fs_type); +} diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 104a62dadb9..1e2006caf15 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -34,6 +34,7 @@ static void fuse_request_init(struct fuse_req *req) { memset(req, 0, sizeof(*req)); INIT_LIST_HEAD(&req->list); + INIT_LIST_HEAD(&req->intr_entry); init_waitqueue_head(&req->waitq); atomic_set(&req->count, 1); } @@ -64,18 +65,6 @@ static void restore_sigs(sigset_t *oldset) sigprocmask(SIG_SETMASK, oldset, NULL); } -/* - * Reset request, so that it can be reused - * - * The caller must be _very_ careful to make sure, that it is holding - * the only reference to req - */ -void fuse_reset_request(struct fuse_req *req) -{ - BUG_ON(atomic_read(&req->count) != 1); - fuse_request_init(req); -} - static void __fuse_get_request(struct fuse_req *req) { atomic_inc(&req->count); @@ -88,6 +77,13 @@ static void __fuse_put_request(struct fuse_req *req) atomic_dec(&req->count); } +static void fuse_req_init_context(struct fuse_req *req) +{ + req->in.h.uid = current->fsuid; + req->in.h.gid = current->fsgid; + req->in.h.pid = current->pid; +} + struct fuse_req *fuse_get_req(struct fuse_conn *fc) { struct fuse_req *req; @@ -103,14 +99,16 @@ struct fuse_req *fuse_get_req(struct fuse_conn *fc) if (intr) goto out; + err = -ENOTCONN; + if (!fc->connected) + goto out; + req = fuse_request_alloc(); err = -ENOMEM; if (!req) goto out; - req->in.h.uid = current->fsuid; - req->in.h.gid = current->fsgid; - req->in.h.pid = current->pid; + fuse_req_init_context(req); req->waiting = 1; return req; @@ -119,142 +117,183 @@ struct fuse_req *fuse_get_req(struct fuse_conn *fc) return ERR_PTR(err); } -void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) +/* + * Return request in fuse_file->reserved_req. However that may + * currently be in use. If that is the case, wait for it to become + * available. + */ +static struct fuse_req *get_reserved_req(struct fuse_conn *fc, + struct file *file) { - if (atomic_dec_and_test(&req->count)) { - if (req->waiting) - atomic_dec(&fc->num_waiting); - fuse_request_free(req); - } + struct fuse_req *req = NULL; + struct fuse_file *ff = file->private_data; + + do { + wait_event(fc->blocked_waitq, ff->reserved_req); + spin_lock(&fc->lock); + if (ff->reserved_req) { + req = ff->reserved_req; + ff->reserved_req = NULL; + get_file(file); + req->stolen_file = file; + } + spin_unlock(&fc->lock); + } while (!req); + + return 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. + * Put stolen request back into fuse_file->reserved_req */ -void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req) +static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req) { - iput(req->inode); - iput(req->inode2); + struct file *file = req->stolen_file; + struct fuse_file *ff = file->private_data; + spin_lock(&fc->lock); - list_del(&req->bg_entry); - if (fc->num_background == FUSE_MAX_BACKGROUND) { - fc->blocked = 0; - wake_up_all(&fc->blocked_waitq); - } - fc->num_background--; + fuse_request_init(req); + BUG_ON(ff->reserved_req); + ff->reserved_req = req; + wake_up(&fc->blocked_waitq); spin_unlock(&fc->lock); + fput(file); } /* - * This function is called when a request is finished. Either a reply - * has arrived or it was interrupted (and not yet sent) or some error - * occurred during communication with userspace, or the device file - * was closed. In case of a background request the reference to the - * stored objects are released. The requester thread is woken up (if - * still waiting), the 'end' callback is called if given, else the - * reference to the request is released + * Gets a requests for a file operation, always succeeds * - * Releasing extra reference for foreground requests must be done - * within the same locked region as setting state to finished. This - * is because fuse_reset_request() may be called after request is - * finished and it must be the sole possessor. If request is - * interrupted and put in the background, it will return with an error - * and hence never be reset and reused. + * This is used for sending the FLUSH request, which must get to + * userspace, due to POSIX locks which may need to be unlocked. * - * Called with fc->lock, unlocks it + * If allocation fails due to OOM, use the reserved request in + * fuse_file. + * + * This is very unlikely to deadlock accidentally, since the + * filesystem should not have it's own file open. If deadlock is + * intentional, it can still be broken by "aborting" the filesystem. */ -static void request_end(struct fuse_conn *fc, struct fuse_req *req) +struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file) { - list_del(&req->list); - req->state = FUSE_REQ_FINISHED; - if (!req->background) { - spin_unlock(&fc->lock); - wake_up(&req->waitq); - fuse_put_request(fc, req); - } else { - void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; - req->end = NULL; - spin_unlock(&fc->lock); - down_read(&fc->sbput_sem); - if (fc->mounted) - fuse_release_background(fc, req); - up_read(&fc->sbput_sem); + struct fuse_req *req; - /* fput must go outside sbput_sem, otherwise it can deadlock */ - if (req->file) - fput(req->file); + atomic_inc(&fc->num_waiting); + wait_event(fc->blocked_waitq, !fc->blocked); + req = fuse_request_alloc(); + if (!req) + req = get_reserved_req(fc, file); - if (end) - end(fc, req); + fuse_req_init_context(req); + req->waiting = 1; + return req; +} + +void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) +{ + if (atomic_dec_and_test(&req->count)) { + if (req->waiting) + atomic_dec(&fc->num_waiting); + + if (req->stolen_file) + put_reserved_req(fc, req); else - fuse_put_request(fc, req); + fuse_request_free(req); } } /* - * Unfortunately request interruption not just solves the deadlock - * problem, it causes problems too. These stem from the fact, that an - * interrupted request is continued to be processed in userspace, - * while all the locks and object references (inode and file) held - * during the operation are released. - * - * To release the locks is exactly why there's a need to interrupt the - * request, so there's not a lot that can be done about this, except - * introduce additional locking in userspace. - * - * More important is to keep inode and file references until userspace - * has replied, otherwise FORGET and RELEASE could be sent while the - * inode/file is still used by the filesystem. - * - * For this reason the concept of "background" request is introduced. - * An interrupted request is backgrounded if it has been already sent - * to userspace. Backgrounding involves getting an extra reference to - * inode(s) or file used in the request, and adding the request to - * fc->background list. When a reply is received for a background - * request, the object references are released, and the request is - * removed from the list. If the filesystem is unmounted while there - * are still background requests, the list is walked and references - * are released as if a reply was received. + * This function is called when a request is finished. Either a reply + * has arrived or it was aborted (and not yet sent) or some error + * occurred during communication with userspace, or the device file + * was closed. The requester thread is woken up (if still waiting), + * the 'end' callback is called if given, else the reference to the + * request is released * - * There's one more use for a background request. The RELEASE message is - * always sent as background, since it doesn't return an error or - * data. + * Called with fc->lock, unlocks it */ -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) - req->inode2 = igrab(req->inode2); +static void request_end(struct fuse_conn *fc, struct fuse_req *req) +{ + void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; + req->end = NULL; + list_del(&req->list); + list_del(&req->intr_entry); + req->state = FUSE_REQ_FINISHED; + if (req->background) { + if (fc->num_background == FUSE_MAX_BACKGROUND) { + fc->blocked = 0; + wake_up_all(&fc->blocked_waitq); + } + fc->num_background--; + } + spin_unlock(&fc->lock); + dput(req->dentry); + mntput(req->vfsmount); if (req->file) - get_file(req->file); + fput(req->file); + wake_up(&req->waitq); + if (end) + end(fc, req); + else + fuse_put_request(fc, req); } -/* Called with fc->lock held. Releases, and then reacquires it. */ -static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) +static void wait_answer_interruptible(struct fuse_conn *fc, + struct fuse_req *req) { - sigset_t oldset; + if (signal_pending(current)) + return; spin_unlock(&fc->lock); - block_sigs(&oldset); wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED); - restore_sigs(&oldset); spin_lock(&fc->lock); - if (req->state == FUSE_REQ_FINISHED && !req->interrupted) - return; +} + +static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req) +{ + list_add_tail(&req->intr_entry, &fc->interrupts); + wake_up(&fc->waitq); + kill_fasync(&fc->fasync, SIGIO, POLL_IN); +} + +/* Called with fc->lock held. Releases, and then reacquires it. */ +static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) +{ + if (!fc->no_interrupt) { + /* Any signal may interrupt this */ + wait_answer_interruptible(fc, req); + + if (req->aborted) + goto aborted; + if (req->state == FUSE_REQ_FINISHED) + return; - if (!req->interrupted) { - req->out.h.error = -EINTR; req->interrupted = 1; + if (req->state == FUSE_REQ_SENT) + queue_interrupt(fc, req); + } + + if (req->force) { + spin_unlock(&fc->lock); + wait_event(req->waitq, req->state == FUSE_REQ_FINISHED); + spin_lock(&fc->lock); + } else { + sigset_t oldset; + + /* Only fatal signals may interrupt this */ + block_sigs(&oldset); + wait_answer_interruptible(fc, req); + restore_sigs(&oldset); } + + if (req->aborted) + goto aborted; + if (req->state == FUSE_REQ_FINISHED) + return; + + req->out.h.error = -EINTR; + req->aborted = 1; + + aborted: if (req->locked) { /* This is uninterruptible sleep, because data is being copied to/from the buffers of req. During @@ -268,8 +307,11 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) if (req->state == FUSE_REQ_PENDING) { list_del(&req->list); __fuse_put_request(req); - } else if (req->state == FUSE_REQ_SENT) - background_request(fc, req); + } else if (req->state == FUSE_REQ_SENT) { + spin_unlock(&fc->lock); + wait_event(req->waitq, req->state == FUSE_REQ_FINISHED); + spin_lock(&fc->lock); + } } static unsigned len_args(unsigned numargs, struct fuse_arg *args) @@ -283,13 +325,19 @@ static unsigned len_args(unsigned numargs, struct fuse_arg *args) return nbytes; } +static u64 fuse_get_unique(struct fuse_conn *fc) + { + fc->reqctr++; + /* zero is special */ + if (fc->reqctr == 0) + fc->reqctr = 1; + + return fc->reqctr; +} + static void queue_request(struct fuse_conn *fc, struct fuse_req *req) { - fc->reqctr++; - /* zero is special */ - if (fc->reqctr == 0) - fc->reqctr = 1; - req->in.h.unique = fc->reqctr; + req->in.h.unique = fuse_get_unique(fc); req->in.h.len = sizeof(struct fuse_in_header) + len_args(req->in.numargs, (struct fuse_arg *) req->in.args); list_add_tail(&req->list, &fc->pending); @@ -302,9 +350,6 @@ static void queue_request(struct fuse_conn *fc, struct fuse_req *req) kill_fasync(&fc->fasync, SIGIO, POLL_IN); } -/* - * This can only be interrupted by a SIGKILL - */ void request_send(struct fuse_conn *fc, struct fuse_req *req) { req->isreply = 1; @@ -327,8 +372,12 @@ void request_send(struct fuse_conn *fc, struct fuse_req *req) static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req) { spin_lock(&fc->lock); - background_request(fc, req); if (fc->connected) { + req->background = 1; + fc->num_background++; + if (fc->num_background == FUSE_MAX_BACKGROUND) + fc->blocked = 1; + queue_request(fc, req); spin_unlock(&fc->lock); } else { @@ -352,14 +401,14 @@ void request_send_background(struct fuse_conn *fc, struct fuse_req *req) /* * Lock the request. Up to the next unlock_request() there mustn't be * anything that could cause a page-fault. If the request was already - * interrupted bail out. + * aborted bail out. */ static int lock_request(struct fuse_conn *fc, struct fuse_req *req) { int err = 0; if (req) { spin_lock(&fc->lock); - if (req->interrupted) + if (req->aborted) err = -ENOENT; else req->locked = 1; @@ -369,7 +418,7 @@ static int lock_request(struct fuse_conn *fc, struct fuse_req *req) } /* - * Unlock request. If it was interrupted during being locked, the + * Unlock request. If it was aborted during being locked, the * requester thread is currently waiting for it to be unlocked, so * wake it up. */ @@ -378,7 +427,7 @@ static void unlock_request(struct fuse_conn *fc, struct fuse_req *req) if (req) { spin_lock(&fc->lock); req->locked = 0; - if (req->interrupted) + if (req->aborted) wake_up(&req->waitq); spin_unlock(&fc->lock); } @@ -557,13 +606,18 @@ static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs, return err; } +static int request_pending(struct fuse_conn *fc) +{ + return !list_empty(&fc->pending) || !list_empty(&fc->interrupts); +} + /* Wait until a request is available on the pending list */ static void request_wait(struct fuse_conn *fc) { DECLARE_WAITQUEUE(wait, current); add_wait_queue_exclusive(&fc->waitq, &wait); - while (fc->connected && list_empty(&fc->pending)) { + while (fc->connected && !request_pending(fc)) { set_current_state(TASK_INTERRUPTIBLE); if (signal_pending(current)) break; @@ -577,11 +631,50 @@ static void request_wait(struct fuse_conn *fc) } /* + * Transfer an interrupt request to userspace + * + * Unlike other requests this is assembled on demand, without a need + * to allocate a separate fuse_req structure. + * + * Called with fc->lock held, releases it + */ +static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_req *req, + const struct iovec *iov, unsigned long nr_segs) +{ + struct fuse_copy_state cs; + struct fuse_in_header ih; + struct fuse_interrupt_in arg; + unsigned reqsize = sizeof(ih) + sizeof(arg); + int err; + + list_del_init(&req->intr_entry); + req->intr_unique = fuse_get_unique(fc); + memset(&ih, 0, sizeof(ih)); + memset(&arg, 0, sizeof(arg)); + ih.len = reqsize; + ih.opcode = FUSE_INTERRUPT; + ih.unique = req->intr_unique; + arg.unique = req->in.h.unique; + + spin_unlock(&fc->lock); + if (iov_length(iov, nr_segs) < reqsize) + return -EINVAL; + + fuse_copy_init(&cs, fc, 1, NULL, iov, nr_segs); + err = fuse_copy_one(&cs, &ih, sizeof(ih)); + if (!err) + err = fuse_copy_one(&cs, &arg, sizeof(arg)); + fuse_copy_finish(&cs); + + return err ? err : reqsize; +} + +/* * Read a single request into the userspace filesystem's buffer. This * function waits until a request is available, then removes it from * the pending list and copies request data to userspace buffer. If - * no reply is needed (FORGET) or request has been interrupted or - * there was an error during the copying then it's finished by calling + * no reply is needed (FORGET) or request has been aborted or there + * was an error during the copying then it's finished by calling * request_end(). Otherwise add it to the processing list, and set * the 'sent' flag. */ @@ -601,7 +694,7 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, spin_lock(&fc->lock); err = -EAGAIN; if ((file->f_flags & O_NONBLOCK) && fc->connected && - list_empty(&fc->pending)) + !request_pending(fc)) goto err_unlock; request_wait(fc); @@ -609,9 +702,15 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, if (!fc->connected) goto err_unlock; err = -ERESTARTSYS; - if (list_empty(&fc->pending)) + if (!request_pending(fc)) goto err_unlock; + if (!list_empty(&fc->interrupts)) { + req = list_entry(fc->interrupts.next, struct fuse_req, + intr_entry); + return fuse_read_interrupt(fc, req, iov, nr_segs); + } + req = list_entry(fc->pending.next, struct fuse_req, list); req->state = FUSE_REQ_READING; list_move(&req->list, &fc->io); @@ -636,10 +735,10 @@ static ssize_t fuse_dev_readv(struct file *file, const struct iovec *iov, fuse_copy_finish(&cs); spin_lock(&fc->lock); req->locked = 0; - if (!err && req->interrupted) + if (!err && req->aborted) err = -ENOENT; if (err) { - if (!req->interrupted) + if (!req->aborted) req->out.h.error = -EIO; request_end(fc, req); return err; @@ -649,6 +748,8 @@ 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); + if (req->interrupted) + queue_interrupt(fc, req); spin_unlock(&fc->lock); } return reqsize; @@ -675,7 +776,7 @@ static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique) list_for_each(entry, &fc->processing) { struct fuse_req *req; req = list_entry(entry, struct fuse_req, list); - if (req->in.h.unique == unique) + if (req->in.h.unique == unique || req->intr_unique == unique) return req; } return NULL; @@ -741,17 +842,33 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, goto err_unlock; req = request_find(fc, oh.unique); - err = -EINVAL; if (!req) goto err_unlock; - if (req->interrupted) { + if (req->aborted) { spin_unlock(&fc->lock); fuse_copy_finish(&cs); spin_lock(&fc->lock); request_end(fc, req); return -ENOENT; } + /* Is it an interrupt reply? */ + if (req->intr_unique == oh.unique) { + err = -EINVAL; + if (nbytes != sizeof(struct fuse_out_header)) + goto err_unlock; + + if (oh.error == -ENOSYS) + fc->no_interrupt = 1; + else if (oh.error == -EAGAIN) + queue_interrupt(fc, req); + + spin_unlock(&fc->lock); + fuse_copy_finish(&cs); + return nbytes; + } + + req->state = FUSE_REQ_WRITING; list_move(&req->list, &fc->io); req->out.h = oh; req->locked = 1; @@ -764,9 +881,9 @@ static ssize_t fuse_dev_writev(struct file *file, const struct iovec *iov, spin_lock(&fc->lock); req->locked = 0; if (!err) { - if (req->interrupted) + if (req->aborted) err = -ENOENT; - } else if (!req->interrupted) + } else if (!req->aborted) req->out.h.error = -EIO; request_end(fc, req); @@ -800,7 +917,7 @@ static unsigned fuse_dev_poll(struct file *file, poll_table *wait) spin_lock(&fc->lock); if (!fc->connected) mask = POLLERR; - else if (!list_empty(&fc->pending)) + else if (request_pending(fc)) mask |= POLLIN | POLLRDNORM; spin_unlock(&fc->lock); @@ -826,7 +943,7 @@ static void end_requests(struct fuse_conn *fc, struct list_head *head) /* * Abort requests under I/O * - * The requests are set to interrupted and finished, and the request + * The requests are set to aborted and finished, and the request * waiter is woken up. This will make request_wait_answer() wait * until the request is unlocked and then return. * @@ -841,7 +958,7 @@ static void end_io_requests(struct fuse_conn *fc) list_entry(fc->io.next, struct fuse_req, list); void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; - req->interrupted = 1; + req->aborted = 1; req->out.h.error = -ECONNABORTED; req->state = FUSE_REQ_FINISHED; list_del_init(&req->list); @@ -874,19 +991,20 @@ static void end_io_requests(struct fuse_conn *fc) * onto the pending list is prevented by req->connected being false. * * Progression of requests under I/O to the processing list is - * prevented by the req->interrupted flag being true for these - * requests. For this reason requests on the io list must be aborted - * first. + * prevented by the req->aborted flag being true for these requests. + * For this reason requests on the io list must be aborted first. */ void fuse_abort_conn(struct fuse_conn *fc) { spin_lock(&fc->lock); if (fc->connected) { fc->connected = 0; + fc->blocked = 0; end_io_requests(fc); end_requests(fc, &fc->pending); end_requests(fc, &fc->processing); wake_up_all(&fc->waitq); + wake_up_all(&fc->blocked_waitq); kill_fasync(&fc->fasync, SIGIO, POLL_IN); } spin_unlock(&fc->lock); @@ -902,7 +1020,7 @@ static int fuse_dev_release(struct inode *inode, struct file *file) end_requests(fc, &fc->processing); spin_unlock(&fc->lock); fasync_helper(-1, file, 0, &fc->fasync); - kobject_put(&fc->kobj); + fuse_conn_put(fc); } return 0; diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 8d7546e832e..72a74cde6de 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.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. @@ -79,7 +79,6 @@ static void fuse_lookup_init(struct fuse_req *req, struct inode *dir, { req->in.h.opcode = FUSE_LOOKUP; req->in.h.nodeid = get_node_id(dir); - req->inode = dir; req->in.numargs = 1; req->in.args[0].size = entry->d_name.len + 1; req->in.args[0].value = entry->d_name.name; @@ -225,6 +224,20 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, } /* + * Synchronous release for the case when something goes wrong in CREATE_OPEN + */ +static void fuse_sync_release(struct fuse_conn *fc, struct fuse_file *ff, + u64 nodeid, int flags) +{ + struct fuse_req *req; + + req = fuse_release_fill(ff, nodeid, flags, FUSE_RELEASE); + req->force = 1; + request_send(fc, req); + fuse_put_request(fc, req); +} + +/* * Atomic create+open operation * * If the filesystem doesn't support this, then fall back to separate @@ -237,6 +250,7 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, struct inode *inode; struct fuse_conn *fc = get_fuse_conn(dir); struct fuse_req *req; + struct fuse_req *forget_req; struct fuse_open_in inarg; struct fuse_open_out outopen; struct fuse_entry_out outentry; @@ -247,9 +261,14 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, if (fc->no_create) return -ENOSYS; + forget_req = fuse_get_req(fc); + if (IS_ERR(forget_req)) + return PTR_ERR(forget_req); + req = fuse_get_req(fc); + err = PTR_ERR(req); if (IS_ERR(req)) - return PTR_ERR(req); + goto out_put_forget_req; err = -ENOMEM; ff = fuse_file_alloc(); @@ -262,7 +281,6 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, inarg.mode = mode; req->in.h.opcode = FUSE_CREATE; req->in.h.nodeid = get_node_id(dir); - req->inode = dir; req->in.numargs = 2; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -285,25 +303,23 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode, if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid)) goto out_free_ff; + fuse_put_request(fc, req); inode = fuse_iget(dir->i_sb, outentry.nodeid, outentry.generation, &outentry.attr); - err = -ENOMEM; if (!inode) { flags &= ~(O_CREAT | O_EXCL | O_TRUNC); ff->fh = outopen.fh; - /* Special release, with inode = NULL, this will - trigger a 'forget' request when the release is - complete */ - fuse_send_release(fc, ff, outentry.nodeid, NULL, flags, 0); - goto out_put_request; + fuse_sync_release(fc, ff, outentry.nodeid, flags); + fuse_send_forget(fc, forget_req, outentry.nodeid, 1); + return -ENOMEM; } - fuse_put_request(fc, req); + fuse_put_request(fc, forget_req); d_instantiate(entry, inode); fuse_change_timeout(entry, &outentry); file = lookup_instantiate_filp(nd, entry, generic_file_open); if (IS_ERR(file)) { ff->fh = outopen.fh; - fuse_send_release(fc, ff, outentry.nodeid, inode, flags, 0); + fuse_sync_release(fc, ff, outentry.nodeid, flags); return PTR_ERR(file); } fuse_finish_open(inode, file, ff, &outopen); @@ -313,6 +329,8 @@ 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_put_forget_req: + fuse_put_request(fc, forget_req); return err; } @@ -328,7 +346,6 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req, int err; req->in.h.nodeid = get_node_id(dir); - req->inode = dir; req->out.numargs = 1; req->out.args[0].size = sizeof(outarg); req->out.args[0].value = &outarg; @@ -448,7 +465,6 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry) req->in.h.opcode = FUSE_UNLINK; req->in.h.nodeid = get_node_id(dir); - req->inode = dir; req->in.numargs = 1; req->in.args[0].size = entry->d_name.len + 1; req->in.args[0].value = entry->d_name.name; @@ -480,7 +496,6 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry) req->in.h.opcode = FUSE_RMDIR; req->in.h.nodeid = get_node_id(dir); - req->inode = dir; req->in.numargs = 1; req->in.args[0].size = entry->d_name.len + 1; req->in.args[0].value = entry->d_name.name; @@ -510,8 +525,6 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent, inarg.newdir = get_node_id(newdir); req->in.h.opcode = FUSE_RENAME; req->in.h.nodeid = get_node_id(olddir); - req->inode = olddir; - req->inode2 = newdir; req->in.numargs = 3; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -558,7 +571,6 @@ static int fuse_link(struct dentry *entry, struct inode *newdir, memset(&inarg, 0, sizeof(inarg)); inarg.oldnodeid = get_node_id(inode); req->in.h.opcode = FUSE_LINK; - req->inode2 = inode; req->in.numargs = 2; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -587,7 +599,6 @@ int fuse_do_getattr(struct inode *inode) req->in.h.opcode = FUSE_GETATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->out.numargs = 1; req->out.args[0].size = sizeof(arg); req->out.args[0].value = &arg; @@ -679,7 +690,6 @@ static int fuse_access(struct inode *inode, int mask) inarg.mask = mask; req->in.h.opcode = FUSE_ACCESS; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -820,7 +830,6 @@ static char *read_link(struct dentry *dentry) } req->in.h.opcode = FUSE_READLINK; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->out.argvar = 1; req->out.numargs = 1; req->out.args[0].size = PAGE_SIZE - 1; @@ -939,7 +948,6 @@ static int fuse_setattr(struct dentry *entry, struct iattr *attr) iattr_to_fattr(attr, &inarg); req->in.h.opcode = FUSE_SETATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -1002,7 +1010,6 @@ static int fuse_setxattr(struct dentry *entry, const char *name, inarg.flags = flags; req->in.h.opcode = FUSE_SETXATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 3; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -1041,7 +1048,6 @@ static ssize_t fuse_getxattr(struct dentry *entry, const char *name, inarg.size = size; req->in.h.opcode = FUSE_GETXATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 2; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -1091,7 +1097,6 @@ static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) inarg.size = size; req->in.h.opcode = FUSE_LISTXATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -1135,7 +1140,6 @@ static int fuse_removexattr(struct dentry *entry, const char *name) req->in.h.opcode = FUSE_REMOVEXATTR; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = strlen(name) + 1; req->in.args[0].value = name; diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 087f3b734f4..28aa81eae2c 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -30,7 +30,6 @@ static int fuse_send_open(struct inode *inode, struct file *file, int isdir, inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -49,8 +48,8 @@ struct fuse_file *fuse_file_alloc(void) struct fuse_file *ff; ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL); if (ff) { - ff->release_req = fuse_request_alloc(); - if (!ff->release_req) { + ff->reserved_req = fuse_request_alloc(); + if (!ff->reserved_req) { kfree(ff); ff = NULL; } @@ -60,7 +59,7 @@ struct fuse_file *fuse_file_alloc(void) void fuse_file_free(struct fuse_file *ff) { - fuse_request_free(ff->release_req); + fuse_request_free(ff->reserved_req); kfree(ff); } @@ -113,37 +112,22 @@ int fuse_open_common(struct inode *inode, struct file *file, int isdir) return err; } -/* Special case for failed iget in CREATE */ -static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req) +struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags, + int opcode) { - /* If called from end_io_requests(), req has more than one - reference and fuse_reset_request() cannot work */ - if (fc->connected) { - u64 nodeid = req->in.h.nodeid; - fuse_reset_request(req); - fuse_send_forget(fc, req, nodeid, 1); - } else - fuse_put_request(fc, req); -} - -void fuse_send_release(struct fuse_conn *fc, struct fuse_file *ff, - u64 nodeid, struct inode *inode, int flags, int isdir) -{ - struct fuse_req * req = ff->release_req; + struct fuse_req *req = ff->reserved_req; struct fuse_release_in *inarg = &req->misc.release_in; inarg->fh = ff->fh; inarg->flags = flags; - req->in.h.opcode = isdir ? FUSE_RELEASEDIR : FUSE_RELEASE; + req->in.h.opcode = opcode; req->in.h.nodeid = nodeid; - req->inode = inode; req->in.numargs = 1; req->in.args[0].size = sizeof(struct fuse_release_in); req->in.args[0].value = inarg; - request_send_background(fc, req); - if (!inode) - req->end = fuse_release_end; kfree(ff); + + return req; } int fuse_release_common(struct inode *inode, struct file *file, int isdir) @@ -151,8 +135,15 @@ int fuse_release_common(struct inode *inode, struct file *file, int isdir) struct fuse_file *ff = file->private_data; if (ff) { struct fuse_conn *fc = get_fuse_conn(inode); - u64 nodeid = get_node_id(inode); - fuse_send_release(fc, ff, nodeid, inode, file->f_flags, isdir); + struct fuse_req *req; + + req = fuse_release_fill(ff, get_node_id(inode), file->f_flags, + isdir ? FUSE_RELEASEDIR : FUSE_RELEASE); + + /* Hold vfsmount and dentry until release is finished */ + req->vfsmount = mntget(file->f_vfsmnt); + req->dentry = dget(file->f_dentry); + request_send_background(fc, req); } /* Return value is ignored by VFS */ @@ -169,6 +160,28 @@ static int fuse_release(struct inode *inode, struct file *file) return fuse_release_common(inode, file, 0); } +/* + * Scramble the ID space with XTEA, so that the value of the files_struct + * pointer is not exposed to userspace. + */ +static u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id) +{ + u32 *k = fc->scramble_key; + u64 v = (unsigned long) id; + u32 v0 = v; + u32 v1 = v >> 32; + u32 sum = 0; + int i; + + for (i = 0; i < 32; i++) { + v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]); + sum += 0x9E3779B9; + v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]); + } + + return (u64) v0 + ((u64) v1 << 32); +} + static int fuse_flush(struct file *file, fl_owner_t id) { struct inode *inode = file->f_dentry->d_inode; @@ -184,19 +197,16 @@ static int fuse_flush(struct file *file, fl_owner_t id) if (fc->no_flush) return 0; - req = fuse_get_req(fc); - if (IS_ERR(req)) - return PTR_ERR(req); - + req = fuse_get_req_nofail(fc, file); memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; + inarg.lock_owner = fuse_lock_owner_id(fc, id); req->in.h.opcode = FUSE_FLUSH; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; - req->file = file; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; + req->force = 1; request_send(fc, req); err = req->out.h.error; fuse_put_request(fc, req); @@ -232,8 +242,6 @@ int fuse_fsync_common(struct file *file, struct dentry *de, int datasync, inarg.fsync_flags = datasync ? 1 : 0; req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; - req->file = file; req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; @@ -266,8 +274,6 @@ void fuse_read_fill(struct fuse_req *req, struct file *file, inarg->size = count; req->in.h.opcode = opcode; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; - req->file = file; req->in.numargs = 1; req->in.args[0].size = sizeof(struct fuse_read_in); req->in.args[0].value = inarg; @@ -342,6 +348,8 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file, req->out.page_zeroing = 1; fuse_read_fill(req, file, inode, pos, count, FUSE_READ); if (fc->async_read) { + get_file(file); + req->file = file; req->end = fuse_readpages_end; request_send_background(fc, req); } else { @@ -420,8 +428,6 @@ static size_t fuse_send_write(struct fuse_req *req, struct file *file, inarg.size = count; req->in.h.opcode = FUSE_WRITE; req->in.h.nodeid = get_node_id(inode); - req->inode = inode; - req->file = file; req->in.argpages = 1; req->in.numargs = 2; req->in.args[0].size = sizeof(struct fuse_write_in); @@ -619,6 +625,126 @@ static int fuse_set_page_dirty(struct page *page) return 0; } +static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, + struct file_lock *fl) +{ + switch (ffl->type) { + case F_UNLCK: + break; + + case F_RDLCK: + case F_WRLCK: + if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || + ffl->end < ffl->start) + return -EIO; + + fl->fl_start = ffl->start; + fl->fl_end = ffl->end; + fl->fl_pid = ffl->pid; + break; + + default: + return -EIO; + } + fl->fl_type = ffl->type; + return 0; +} + +static void fuse_lk_fill(struct fuse_req *req, struct file *file, + const struct file_lock *fl, int opcode, pid_t pid) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_lk_in *arg = &req->misc.lk_in; + + arg->fh = ff->fh; + arg->owner = fuse_lock_owner_id(fc, fl->fl_owner); + arg->lk.start = fl->fl_start; + arg->lk.end = fl->fl_end; + arg->lk.type = fl->fl_type; + arg->lk.pid = pid; + req->in.h.opcode = opcode; + req->in.h.nodeid = get_node_id(inode); + req->in.numargs = 1; + req->in.args[0].size = sizeof(*arg); + req->in.args[0].value = arg; +} + +static int fuse_getlk(struct file *file, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_req *req; + struct fuse_lk_out outarg; + int err; + + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); + + fuse_lk_fill(req, file, fl, FUSE_GETLK, 0); + req->out.numargs = 1; + req->out.args[0].size = sizeof(outarg); + req->out.args[0].value = &outarg; + request_send(fc, req); + err = req->out.h.error; + fuse_put_request(fc, req); + if (!err) + err = convert_fuse_file_lock(&outarg.lk, fl); + + return err; +} + +static int fuse_setlk(struct file *file, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_req *req; + int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; + pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; + int err; + + /* Unlock on close is handled by the flush method */ + if (fl->fl_flags & FL_CLOSE) + return 0; + + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); + + fuse_lk_fill(req, file, fl, opcode, pid); + request_send(fc, req); + err = req->out.h.error; + /* locking is restartable */ + if (err == -EINTR) + err = -ERESTARTSYS; + fuse_put_request(fc, req); + return err; +} + +static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + int err; + + if (cmd == F_GETLK) { + if (fc->no_lock) { + if (!posix_test_lock(file, fl, fl)) + fl->fl_type = F_UNLCK; + err = 0; + } else + err = fuse_getlk(file, fl); + } else { + if (fc->no_lock) + err = posix_lock_file_wait(file, fl); + else + err = fuse_setlk(file, fl); + } + return err; +} + static const struct file_operations fuse_file_operations = { .llseek = generic_file_llseek, .read = generic_file_read, @@ -628,6 +754,7 @@ static const struct file_operations fuse_file_operations = { .flush = fuse_flush, .release = fuse_release, .fsync = fuse_fsync, + .lock = fuse_file_lock, .sendfile = generic_file_sendfile, }; @@ -639,6 +766,7 @@ static const struct file_operations fuse_direct_io_file_operations = { .flush = fuse_flush, .release = fuse_release, .fsync = fuse_fsync, + .lock = fuse_file_lock, /* no mmap and sendfile */ }; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 0474202cb5d..0dbf9662184 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -8,12 +8,13 @@ #include <linux/fuse.h> #include <linux/fs.h> +#include <linux/mount.h> #include <linux/wait.h> #include <linux/list.h> #include <linux/spinlock.h> #include <linux/mm.h> #include <linux/backing-dev.h> -#include <asm/semaphore.h> +#include <linux/mutex.h> /** Max number of pages that can be used in a single read request */ #define FUSE_MAX_PAGES_PER_REQ 32 @@ -24,6 +25,9 @@ /** It could be as large as PATH_MAX, but would that have any uses? */ #define FUSE_NAME_MAX 1024 +/** Number of dentries for each connection in the control filesystem */ +#define FUSE_CTL_NUM_DENTRIES 3 + /** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem module will check permissions based on the file mode. Otherwise no permission checking is done in the kernel */ @@ -33,6 +37,11 @@ doing the mount will be allowed to access the filesystem */ #define FUSE_ALLOW_OTHER (1 << 1) +/** List of active connections */ +extern struct list_head fuse_conn_list; + +/** Global mutex protecting fuse_conn_list and the control filesystem */ +extern struct mutex fuse_mutex; /** FUSE inode */ struct fuse_inode { @@ -56,7 +65,7 @@ struct fuse_inode { /** FUSE specific file data */ struct fuse_file { /** Request reserved for flush and release */ - struct fuse_req *release_req; + struct fuse_req *reserved_req; /** File handle used by userspace */ u64 fh; @@ -122,6 +131,7 @@ enum fuse_req_state { FUSE_REQ_PENDING, FUSE_REQ_READING, FUSE_REQ_SENT, + FUSE_REQ_WRITING, FUSE_REQ_FINISHED }; @@ -135,12 +145,15 @@ struct fuse_req { fuse_conn */ struct list_head list; - /** Entry on the background list */ - struct list_head bg_entry; + /** Entry on the interrupts list */ + struct list_head intr_entry; /** refcount */ atomic_t count; + /** Unique ID for the interrupt request */ + u64 intr_unique; + /* * The following bitfields are either set once before the * request is queued or setting/clearing them is protected by @@ -150,12 +163,18 @@ struct fuse_req { /** True if the request has reply */ unsigned isreply:1; - /** The request was interrupted */ - unsigned interrupted:1; + /** Force sending of the request even if interrupted */ + unsigned force:1; + + /** The request was aborted */ + unsigned aborted:1; /** Request is sent in the background */ unsigned background:1; + /** The request has been interrupted */ + unsigned interrupted:1; + /** Data is being copied to/from the request */ unsigned locked:1; @@ -181,6 +200,7 @@ struct fuse_req { struct fuse_init_in init_in; struct fuse_init_out init_out; struct fuse_read_in read_in; + struct fuse_lk_in lk_in; } misc; /** page vector */ @@ -192,17 +212,20 @@ struct fuse_req { /** offset of data on first page */ unsigned page_offset; - /** Inode used in the request */ - struct inode *inode; - - /** Second inode used in the request (or NULL) */ - struct inode *inode2; - /** File used in the request (or NULL) */ struct file *file; + /** vfsmount used in release */ + struct vfsmount *vfsmount; + + /** dentry used in release */ + struct dentry *dentry; + /** Request completion callback */ void (*end)(struct fuse_conn *, struct fuse_req *); + + /** Request is stolen from fuse_file->reserved_req */ + struct file *stolen_file; }; /** @@ -216,6 +239,9 @@ struct fuse_conn { /** Lock protecting accessess to members of this structure */ spinlock_t lock; + /** Refcount */ + atomic_t count; + /** The user id for this mount */ uid_t user_id; @@ -243,13 +269,12 @@ struct fuse_conn { /** The list of requests under I/O */ struct list_head io; - /** Requests put in the background (RELEASE or any other - interrupted request) */ - struct list_head background; - /** Number of requests currently in the background */ unsigned num_background; + /** Pending interrupts */ + struct list_head interrupts; + /** 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 */ @@ -258,15 +283,9 @@ struct fuse_conn { /** waitq for blocked connection */ wait_queue_head_t blocked_waitq; - /** RW semaphore for exclusion with fuse_put_super() */ - struct rw_semaphore sbput_sem; - /** The next unique request id */ u64 reqctr; - /** Mount is active */ - unsigned mounted; - /** Connection established, cleared on umount, connection abort and device release */ unsigned connected; @@ -305,12 +324,18 @@ struct fuse_conn { /** Is removexattr not implemented by fs? */ unsigned no_removexattr : 1; + /** Are file locking primitives not implemented by fs? */ + unsigned no_lock : 1; + /** Is access not implemented by fs? */ unsigned no_access : 1; /** Is create not implemented by fs? */ unsigned no_create : 1; + /** Is interrupt not implemented by fs? */ + unsigned no_interrupt : 1; + /** The number of requests waiting for completion */ atomic_t num_waiting; @@ -320,11 +345,23 @@ struct fuse_conn { /** Backing dev info */ struct backing_dev_info bdi; - /** kobject */ - struct kobject kobj; + /** Entry on the fuse_conn_list */ + struct list_head entry; + + /** Unique ID */ + u64 id; + + /** Dentries in the control filesystem */ + struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES]; + + /** number of dentries used in the above array */ + int ctl_ndents; /** O_ASYNC requests */ struct fasync_struct *fasync; + + /** Key for lock owner ID scrambling */ + u32 scramble_key[4]; }; static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb) @@ -337,11 +374,6 @@ static inline struct fuse_conn *get_fuse_conn(struct inode *inode) return get_fuse_conn_super(inode->i_sb); } -static inline struct fuse_conn *get_fuse_conn_kobj(struct kobject *obj) -{ - return container_of(obj, struct fuse_conn, kobj); -} - static inline struct fuse_inode *get_fuse_inode(struct inode *inode) { return container_of(inode, struct fuse_inode, inode); @@ -383,12 +415,9 @@ void fuse_file_free(struct fuse_file *ff); void fuse_finish_open(struct inode *inode, struct file *file, struct fuse_file *ff, struct fuse_open_out *outarg); -/** - * Send a RELEASE request - */ -void fuse_send_release(struct fuse_conn *fc, struct fuse_file *ff, - u64 nodeid, struct inode *inode, int flags, int isdir); - +/** */ +struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags, + int opcode); /** * Send RELEASE or RELEASEDIR request */ @@ -435,6 +464,9 @@ int fuse_dev_init(void); */ void fuse_dev_cleanup(void); +int fuse_ctl_init(void); +void fuse_ctl_cleanup(void); + /** * Allocate a request */ @@ -446,14 +478,14 @@ struct fuse_req *fuse_request_alloc(void); void fuse_request_free(struct fuse_req *req); /** - * Reinitialize a request, the preallocated flag is left unmodified + * Get a request, may fail with -ENOMEM */ -void fuse_reset_request(struct fuse_req *req); +struct fuse_req *fuse_get_req(struct fuse_conn *fc); /** - * Reserve a preallocated request + * Gets a requests for a file operation, always succeeds */ -struct fuse_req *fuse_get_req(struct fuse_conn *fc); +struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file); /** * Decrement reference count of a request. If count goes to zero free @@ -476,11 +508,6 @@ void request_send_noreply(struct fuse_conn *fc, struct fuse_req *req); */ void request_send_background(struct fuse_conn *fc, struct fuse_req *req); -/** - * Release inodes and file associated with background request - */ -void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req); - /* Abort all requests */ void fuse_abort_conn(struct fuse_conn *fc); @@ -493,3 +520,23 @@ int fuse_do_getattr(struct inode *inode); * Invalidate inode attributes */ void fuse_invalidate_attr(struct inode *inode); + +/** + * Acquire reference to fuse_conn + */ +struct fuse_conn *fuse_conn_get(struct fuse_conn *fc); + +/** + * Release reference to fuse_conn + */ +void fuse_conn_put(struct fuse_conn *fc); + +/** + * Add connection to control filesystem + */ +int fuse_ctl_add_conn(struct fuse_conn *fc); + +/** + * Remove connection from control filesystem + */ +void fuse_ctl_remove_conn(struct fuse_conn *fc); diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 815c824f4fc..dcaaabd3b9c 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -11,25 +11,20 @@ #include <linux/pagemap.h> #include <linux/slab.h> #include <linux/file.h> -#include <linux/mount.h> #include <linux/seq_file.h> #include <linux/init.h> #include <linux/module.h> #include <linux/parser.h> #include <linux/statfs.h> +#include <linux/random.h> MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); MODULE_DESCRIPTION("Filesystem in Userspace"); MODULE_LICENSE("GPL"); static kmem_cache_t *fuse_inode_cachep; -static struct subsystem connections_subsys; - -struct fuse_conn_attr { - struct attribute attr; - ssize_t (*show)(struct fuse_conn *, char *); - ssize_t (*store)(struct fuse_conn *, const char *, size_t); -}; +struct list_head fuse_conn_list; +DEFINE_MUTEX(fuse_mutex); #define FUSE_SUPER_MAGIC 0x65735546 @@ -104,6 +99,14 @@ static void fuse_clear_inode(struct inode *inode) } } +static int fuse_remount_fs(struct super_block *sb, int *flags, char *data) +{ + if (*flags & MS_MANDLOCK) + return -EINVAL; + + return 0; +} + void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr) { if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size) @@ -205,22 +208,19 @@ static void fuse_put_super(struct super_block *sb) { struct fuse_conn *fc = get_fuse_conn_super(sb); - down_write(&fc->sbput_sem); - while (!list_empty(&fc->background)) - fuse_release_background(fc, - list_entry(fc->background.next, - struct fuse_req, bg_entry)); - spin_lock(&fc->lock); - fc->mounted = 0; fc->connected = 0; + fc->blocked = 0; 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); + wake_up_all(&fc->blocked_waitq); + mutex_lock(&fuse_mutex); + list_del(&fc->entry); + fuse_ctl_remove_conn(fc); + mutex_unlock(&fuse_mutex); + fuse_conn_put(fc); } static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) @@ -370,11 +370,6 @@ static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt) return 0; } -static void fuse_conn_release(struct kobject *kobj) -{ - kfree(get_fuse_conn_kobj(kobj)); -} - static struct fuse_conn *new_conn(void) { struct fuse_conn *fc; @@ -382,24 +377,35 @@ static struct fuse_conn *new_conn(void) fc = kzalloc(sizeof(*fc), GFP_KERNEL); if (fc) { spin_lock_init(&fc->lock); + atomic_set(&fc->count, 1); 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->background); - init_rwsem(&fc->sbput_sem); - kobj_set_kset_s(fc, connections_subsys); - kobject_init(&fc->kobj); + INIT_LIST_HEAD(&fc->interrupts); atomic_set(&fc->num_waiting, 0); 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; + get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); } return fc; } +void fuse_conn_put(struct fuse_conn *fc) +{ + if (atomic_dec_and_test(&fc->count)) + kfree(fc); +} + +struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) +{ + atomic_inc(&fc->count); + return fc; +} + static struct inode *get_root_inode(struct super_block *sb, unsigned mode) { struct fuse_attr attr; @@ -415,6 +421,7 @@ static struct super_operations fuse_super_operations = { .destroy_inode = fuse_destroy_inode, .read_inode = fuse_read_inode, .clear_inode = fuse_clear_inode, + .remount_fs = fuse_remount_fs, .put_super = fuse_put_super, .umount_begin = fuse_umount_begin, .statfs = fuse_statfs, @@ -434,8 +441,12 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) ra_pages = arg->max_readahead / PAGE_CACHE_SIZE; if (arg->flags & FUSE_ASYNC_READ) fc->async_read = 1; - } else + if (!(arg->flags & FUSE_POSIX_LOCKS)) + fc->no_lock = 1; + } else { ra_pages = fc->max_read / PAGE_CACHE_SIZE; + fc->no_lock = 1; + } fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages); fc->minor = arg->minor; @@ -453,7 +464,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) arg->major = FUSE_KERNEL_VERSION; arg->minor = FUSE_KERNEL_MINOR_VERSION; arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE; - arg->flags |= FUSE_ASYNC_READ; + arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS; req->in.h.opcode = FUSE_INIT; req->in.numargs = 1; req->in.args[0].size = sizeof(*arg); @@ -469,10 +480,9 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) request_send_background(fc, req); } -static unsigned long long conn_id(void) +static u64 conn_id(void) { - /* BKL is held for ->get_sb() */ - static unsigned long long ctr = 1; + static u64 ctr = 1; return ctr++; } @@ -486,6 +496,9 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) struct fuse_req *init_req; int err; + if (sb->s_flags & MS_MANDLOCK) + return -EINVAL; + if (!parse_fuse_opt((char *) data, &d)) return -EINVAL; @@ -529,25 +542,21 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) if (!init_req) goto err_put_root; - err = kobject_set_name(&fc->kobj, "%llu", conn_id()); - if (err) - goto err_free_req; - - err = kobject_add(&fc->kobj); - if (err) - goto err_free_req; - - /* Setting file->private_data can't race with other mount() - instances, since BKL is held for ->get_sb() */ + mutex_lock(&fuse_mutex); err = -EINVAL; if (file->private_data) - goto err_kobject_del; + goto err_unlock; + fc->id = conn_id(); + err = fuse_ctl_add_conn(fc); + if (err) + goto err_unlock; + + list_add_tail(&fc->entry, &fuse_conn_list); sb->s_root = root_dentry; - fc->mounted = 1; fc->connected = 1; - kobject_get(&fc->kobj); - file->private_data = fc; + file->private_data = fuse_conn_get(fc); + mutex_unlock(&fuse_mutex); /* * atomic_dec_and_test() in fput() provides the necessary * memory barrier for file->private_data to be visible on all @@ -559,15 +568,14 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) return 0; - err_kobject_del: - kobject_del(&fc->kobj); - err_free_req: + err_unlock: + mutex_unlock(&fuse_mutex); fuse_request_free(init_req); err_put_root: dput(root_dentry); err: fput(file); - kobject_put(&fc->kobj); + fuse_conn_put(fc); return err; } @@ -585,68 +593,8 @@ static struct file_system_type fuse_fs_type = { .kill_sb = kill_anon_super, }; -static ssize_t fuse_conn_waiting_show(struct fuse_conn *fc, char *page) -{ - return sprintf(page, "%i\n", atomic_read(&fc->num_waiting)); -} - -static ssize_t fuse_conn_abort_store(struct fuse_conn *fc, const char *page, - size_t count) -{ - fuse_abort_conn(fc); - return count; -} - -static struct fuse_conn_attr fuse_conn_waiting = - __ATTR(waiting, 0400, fuse_conn_waiting_show, NULL); -static struct fuse_conn_attr fuse_conn_abort = - __ATTR(abort, 0600, NULL, fuse_conn_abort_store); - -static struct attribute *fuse_conn_attrs[] = { - &fuse_conn_waiting.attr, - &fuse_conn_abort.attr, - NULL, -}; - -static ssize_t fuse_conn_attr_show(struct kobject *kobj, - struct attribute *attr, - char *page) -{ - struct fuse_conn_attr *fca = - container_of(attr, struct fuse_conn_attr, attr); - - if (fca->show) - return fca->show(get_fuse_conn_kobj(kobj), page); - else - return -EACCES; -} - -static ssize_t fuse_conn_attr_store(struct kobject *kobj, - struct attribute *attr, - const char *page, size_t count) -{ - struct fuse_conn_attr *fca = - container_of(attr, struct fuse_conn_attr, attr); - - if (fca->store) - return fca->store(get_fuse_conn_kobj(kobj), page, count); - else - return -EACCES; -} - -static struct sysfs_ops fuse_conn_sysfs_ops = { - .show = &fuse_conn_attr_show, - .store = &fuse_conn_attr_store, -}; - -static struct kobj_type ktype_fuse_conn = { - .release = fuse_conn_release, - .sysfs_ops = &fuse_conn_sysfs_ops, - .default_attrs = fuse_conn_attrs, -}; - static decl_subsys(fuse, NULL, NULL); -static decl_subsys(connections, &ktype_fuse_conn, NULL); +static decl_subsys(connections, NULL, NULL); static void fuse_inode_init_once(void *foo, kmem_cache_t *cachep, unsigned long flags) @@ -720,6 +668,7 @@ static int __init fuse_init(void) printk("fuse init (API version %i.%i)\n", FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION); + INIT_LIST_HEAD(&fuse_conn_list); res = fuse_fs_init(); if (res) goto err; @@ -732,8 +681,14 @@ static int __init fuse_init(void) if (res) goto err_dev_cleanup; + res = fuse_ctl_init(); + if (res) + goto err_sysfs_cleanup; + return 0; + err_sysfs_cleanup: + fuse_sysfs_cleanup(); err_dev_cleanup: fuse_dev_cleanup(); err_fs_cleanup: @@ -746,6 +701,7 @@ static void __exit fuse_exit(void) { printk(KERN_DEBUG "fuse exit\n"); + fuse_ctl_cleanup(); fuse_sysfs_cleanup(); fuse_fs_cleanup(); fuse_dev_cleanup(); |