diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/fuse/dev.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/fuse/dev.c | 2104 |
1 files changed, 0 insertions, 2104 deletions
diff --git a/ANDROID_3.4.5/fs/fuse/dev.c b/ANDROID_3.4.5/fs/fuse/dev.c deleted file mode 100644 index ceb3b29c..00000000 --- a/ANDROID_3.4.5/fs/fuse/dev.c +++ /dev/null @@ -1,2104 +0,0 @@ -/* - FUSE: Filesystem in Userspace - Copyright (C) 2001-2008 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> -#include <linux/poll.h> -#include <linux/uio.h> -#include <linux/miscdevice.h> -#include <linux/pagemap.h> -#include <linux/file.h> -#include <linux/slab.h> -#include <linux/pipe_fs_i.h> -#include <linux/swap.h> -#include <linux/splice.h> -#include <linux/freezer.h> - -MODULE_ALIAS_MISCDEV(FUSE_MINOR); -MODULE_ALIAS("devname:fuse"); - -static struct kmem_cache *fuse_req_cachep; - -static struct fuse_conn *fuse_get_conn(struct file *file) -{ - /* - * 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) -{ - 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); -} - -struct fuse_req *fuse_request_alloc(void) -{ - struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL); - if (req) - fuse_request_init(req); - return req; -} -EXPORT_SYMBOL_GPL(fuse_request_alloc); - -struct fuse_req *fuse_request_alloc_nofs(void) -{ - struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_NOFS); - if (req) - fuse_request_init(req); - return req; -} - -void fuse_request_free(struct fuse_req *req) -{ - kmem_cache_free(fuse_req_cachep, req); -} - -static void block_sigs(sigset_t *oldset) -{ - sigset_t mask; - - siginitsetinv(&mask, sigmask(SIGKILL)); - sigprocmask(SIG_BLOCK, &mask, oldset); -} - -static void restore_sigs(sigset_t *oldset) -{ - sigprocmask(SIG_SETMASK, oldset, NULL); -} - -static void __fuse_get_request(struct fuse_req *req) -{ - atomic_inc(&req->count); -} - -/* Must be called with > 1 refcount */ -static void __fuse_put_request(struct fuse_req *req) -{ - BUG_ON(atomic_read(&req->count) < 2); - 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; - sigset_t oldset; - int intr; - int err; - - atomic_inc(&fc->num_waiting); - block_sigs(&oldset); - intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked); - restore_sigs(&oldset); - err = -EINTR; - if (intr) - goto out; - - err = -ENOTCONN; - if (!fc->connected) - goto out; - - req = fuse_request_alloc(); - err = -ENOMEM; - if (!req) - goto out; - - fuse_req_init_context(req); - req->waiting = 1; - return req; - - out: - atomic_dec(&fc->num_waiting); - return ERR_PTR(err); -} -EXPORT_SYMBOL_GPL(fuse_get_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) -{ - struct fuse_req *req = NULL; - struct fuse_file *ff = file->private_data; - - do { - wait_event(fc->reserved_req_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; -} - -/* - * Put stolen request back into fuse_file->reserved_req - */ -static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req) -{ - struct file *file = req->stolen_file; - struct fuse_file *ff = file->private_data; - - spin_lock(&fc->lock); - fuse_request_init(req); - BUG_ON(ff->reserved_req); - ff->reserved_req = req; - wake_up_all(&fc->reserved_req_waitq); - spin_unlock(&fc->lock); - fput(file); -} - -/* - * Gets a requests for a file operation, always succeeds - * - * This is used for sending the FLUSH request, which must get to - * userspace, due to POSIX locks which may need to be unlocked. - * - * 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. - */ -struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file) -{ - struct fuse_req *req; - - atomic_inc(&fc->num_waiting); - wait_event(fc->blocked_waitq, !fc->blocked); - req = fuse_request_alloc(); - if (!req) - req = get_reserved_req(fc, file); - - 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_request_free(req); - } -} -EXPORT_SYMBOL_GPL(fuse_put_request); - -static unsigned len_args(unsigned numargs, struct fuse_arg *args) -{ - unsigned nbytes = 0; - unsigned i; - - for (i = 0; i < numargs; i++) - nbytes += args[i].size; - - 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) -{ - 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); - 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); -} - -void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget, - u64 nodeid, u64 nlookup) -{ - forget->forget_one.nodeid = nodeid; - forget->forget_one.nlookup = nlookup; - - spin_lock(&fc->lock); - if (fc->connected) { - fc->forget_list_tail->next = forget; - fc->forget_list_tail = forget; - wake_up(&fc->waitq); - kill_fasync(&fc->fasync, SIGIO, POLL_IN); - } else { - kfree(forget); - } - spin_unlock(&fc->lock); -} - -static void flush_bg_queue(struct fuse_conn *fc) -{ - while (fc->active_background < fc->max_background && - !list_empty(&fc->bg_queue)) { - struct fuse_req *req; - - req = list_entry(fc->bg_queue.next, struct fuse_req, list); - list_del(&req->list); - fc->active_background++; - req->in.h.unique = fuse_get_unique(fc); - queue_request(fc, req); - } -} - -/* - * 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 - * - * Called with fc->lock, unlocks it - */ -static void request_end(struct fuse_conn *fc, struct fuse_req *req) -__releases(fc->lock) -{ - 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 == fc->max_background) { - fc->blocked = 0; - wake_up_all(&fc->blocked_waitq); - } - if (fc->num_background == fc->congestion_threshold && - fc->connected && fc->bdi_initialized) { - clear_bdi_congested(&fc->bdi, BLK_RW_SYNC); - clear_bdi_congested(&fc->bdi, BLK_RW_ASYNC); - } - fc->num_background--; - fc->active_background--; - flush_bg_queue(fc); - } - spin_unlock(&fc->lock); - wake_up(&req->waitq); - if (end) - end(fc, req); - fuse_put_request(fc, req); -} - -static void wait_answer_interruptible(struct fuse_conn *fc, - struct fuse_req *req) -__releases(fc->lock) -__acquires(fc->lock) -{ - if (signal_pending(current)) - return; - - spin_unlock(&fc->lock); - wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED); - spin_lock(&fc->lock); -} - -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); -} - -static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) -__releases(fc->lock) -__acquires(fc->lock) -{ - 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; - - req->interrupted = 1; - if (req->state == FUSE_REQ_SENT) - queue_interrupt(fc, req); - } - - if (!req->force) { - 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; - - /* Request is not yet in userspace, bail out */ - if (req->state == FUSE_REQ_PENDING) { - list_del(&req->list); - __fuse_put_request(req); - req->out.h.error = -EINTR; - return; - } - } - - /* - * Either request is already in userspace, or it was forced. - * Wait it out. - */ - spin_unlock(&fc->lock); - - while (req->state != FUSE_REQ_FINISHED) - wait_event_freezable(req->waitq, - req->state == FUSE_REQ_FINISHED); - spin_lock(&fc->lock); - - if (!req->aborted) - return; - - aborted: - BUG_ON(req->state != FUSE_REQ_FINISHED); - if (req->locked) { - /* This is uninterruptible sleep, because data is - being copied to/from the buffers of req. During - locked state, there mustn't be any filesystem - operation (e.g. page fault), since that could lead - to deadlock */ - spin_unlock(&fc->lock); - wait_event(req->waitq, !req->locked); - spin_lock(&fc->lock); - } -} - -void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req) -{ - req->isreply = 1; - spin_lock(&fc->lock); - if (!fc->connected) - req->out.h.error = -ENOTCONN; - else if (fc->conn_error) - req->out.h.error = -ECONNREFUSED; - else { - req->in.h.unique = fuse_get_unique(fc); - queue_request(fc, req); - /* acquire extra reference, since request is still needed - after request_end() */ - __fuse_get_request(req); - - request_wait_answer(fc, req); - } - spin_unlock(&fc->lock); -} -EXPORT_SYMBOL_GPL(fuse_request_send); - -static void fuse_request_send_nowait_locked(struct fuse_conn *fc, - struct fuse_req *req) -{ - req->background = 1; - fc->num_background++; - if (fc->num_background == fc->max_background) - fc->blocked = 1; - if (fc->num_background == fc->congestion_threshold && - fc->bdi_initialized) { - set_bdi_congested(&fc->bdi, BLK_RW_SYNC); - set_bdi_congested(&fc->bdi, BLK_RW_ASYNC); - } - list_add_tail(&req->list, &fc->bg_queue); - flush_bg_queue(fc); -} - -static void fuse_request_send_nowait(struct fuse_conn *fc, struct fuse_req *req) -{ - spin_lock(&fc->lock); - if (fc->connected) { - fuse_request_send_nowait_locked(fc, req); - spin_unlock(&fc->lock); - } else { - req->out.h.error = -ENOTCONN; - request_end(fc, req); - } -} - -void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req) -{ - req->isreply = 1; - fuse_request_send_nowait(fc, req); -} -EXPORT_SYMBOL_GPL(fuse_request_send_background); - -static int fuse_request_send_notify_reply(struct fuse_conn *fc, - struct fuse_req *req, u64 unique) -{ - int err = -ENODEV; - - req->isreply = 0; - req->in.h.unique = unique; - spin_lock(&fc->lock); - if (fc->connected) { - queue_request(fc, req); - err = 0; - } - spin_unlock(&fc->lock); - - return err; -} - -/* - * Called under fc->lock - * - * fc->connected must have been checked previously - */ -void fuse_request_send_background_locked(struct fuse_conn *fc, - struct fuse_req *req) -{ - req->isreply = 1; - fuse_request_send_nowait_locked(fc, 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 - * 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->aborted) - err = -ENOENT; - else - req->locked = 1; - spin_unlock(&fc->lock); - } - return err; -} - -/* - * Unlock request. If it was aborted during being locked, the - * requester thread is currently waiting for it to be unlocked, so - * wake it up. - */ -static void unlock_request(struct fuse_conn *fc, struct fuse_req *req) -{ - if (req) { - spin_lock(&fc->lock); - req->locked = 0; - if (req->aborted) - wake_up(&req->waitq); - spin_unlock(&fc->lock); - } -} - -struct fuse_copy_state { - struct fuse_conn *fc; - int write; - struct fuse_req *req; - const struct iovec *iov; - struct pipe_buffer *pipebufs; - struct pipe_buffer *currbuf; - struct pipe_inode_info *pipe; - unsigned long nr_segs; - unsigned long seglen; - unsigned long addr; - struct page *pg; - void *mapaddr; - void *buf; - unsigned len; - unsigned move_pages:1; -}; - -static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc, - int write, - const struct iovec *iov, unsigned long nr_segs) -{ - memset(cs, 0, sizeof(*cs)); - cs->fc = fc; - cs->write = write; - cs->iov = iov; - cs->nr_segs = nr_segs; -} - -/* Unmap and put previous page of userspace buffer */ -static void fuse_copy_finish(struct fuse_copy_state *cs) -{ - if (cs->currbuf) { - struct pipe_buffer *buf = cs->currbuf; - - if (!cs->write) { - buf->ops->unmap(cs->pipe, buf, cs->mapaddr); - } else { - kunmap(buf->page); - buf->len = PAGE_SIZE - cs->len; - } - cs->currbuf = NULL; - cs->mapaddr = NULL; - } else if (cs->mapaddr) { - kunmap(cs->pg); - if (cs->write) { - flush_dcache_page(cs->pg); - set_page_dirty_lock(cs->pg); - } - put_page(cs->pg); - cs->mapaddr = NULL; - } -} - -/* - * Get another pagefull of userspace buffer, and map it to kernel - * address space, and lock request - */ -static int fuse_copy_fill(struct fuse_copy_state *cs) -{ - unsigned long offset; - int err; - - unlock_request(cs->fc, cs->req); - fuse_copy_finish(cs); - if (cs->pipebufs) { - struct pipe_buffer *buf = cs->pipebufs; - - if (!cs->write) { - err = buf->ops->confirm(cs->pipe, buf); - if (err) - return err; - - BUG_ON(!cs->nr_segs); - cs->currbuf = buf; - cs->mapaddr = buf->ops->map(cs->pipe, buf, 0); - cs->len = buf->len; - cs->buf = cs->mapaddr + buf->offset; - cs->pipebufs++; - cs->nr_segs--; - } else { - struct page *page; - - if (cs->nr_segs == cs->pipe->buffers) - return -EIO; - - page = alloc_page(GFP_HIGHUSER); - if (!page) - return -ENOMEM; - - buf->page = page; - buf->offset = 0; - buf->len = 0; - - cs->currbuf = buf; - cs->mapaddr = kmap(page); - cs->buf = cs->mapaddr; - cs->len = PAGE_SIZE; - cs->pipebufs++; - cs->nr_segs++; - } - } else { - if (!cs->seglen) { - BUG_ON(!cs->nr_segs); - cs->seglen = cs->iov[0].iov_len; - cs->addr = (unsigned long) cs->iov[0].iov_base; - cs->iov++; - cs->nr_segs--; - } - err = get_user_pages_fast(cs->addr, 1, cs->write, &cs->pg); - if (err < 0) - return err; - BUG_ON(err != 1); - offset = cs->addr % PAGE_SIZE; - cs->mapaddr = kmap(cs->pg); - cs->buf = cs->mapaddr + offset; - cs->len = min(PAGE_SIZE - offset, cs->seglen); - cs->seglen -= cs->len; - cs->addr += cs->len; - } - - return lock_request(cs->fc, cs->req); -} - -/* Do as much copy to/from userspace buffer as we can */ -static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size) -{ - unsigned ncpy = min(*size, cs->len); - if (val) { - if (cs->write) - memcpy(cs->buf, *val, ncpy); - else - memcpy(*val, cs->buf, ncpy); - *val += ncpy; - } - *size -= ncpy; - cs->len -= ncpy; - cs->buf += ncpy; - return ncpy; -} - -static int fuse_check_page(struct page *page) -{ - if (page_mapcount(page) || - page->mapping != NULL || - page_count(page) != 1 || - (page->flags & PAGE_FLAGS_CHECK_AT_PREP & - ~(1 << PG_locked | - 1 << PG_referenced | - 1 << PG_uptodate | - 1 << PG_lru | - 1 << PG_active | - 1 << PG_reclaim))) { - printk(KERN_WARNING "fuse: trying to steal weird page\n"); - printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping); - return 1; - } - return 0; -} - -static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) -{ - int err; - struct page *oldpage = *pagep; - struct page *newpage; - struct pipe_buffer *buf = cs->pipebufs; - struct address_space *mapping; - pgoff_t index; - - unlock_request(cs->fc, cs->req); - fuse_copy_finish(cs); - - err = buf->ops->confirm(cs->pipe, buf); - if (err) - return err; - - BUG_ON(!cs->nr_segs); - cs->currbuf = buf; - cs->len = buf->len; - cs->pipebufs++; - cs->nr_segs--; - - if (cs->len != PAGE_SIZE) - goto out_fallback; - - if (buf->ops->steal(cs->pipe, buf) != 0) - goto out_fallback; - - newpage = buf->page; - - if (WARN_ON(!PageUptodate(newpage))) - return -EIO; - - ClearPageMappedToDisk(newpage); - - if (fuse_check_page(newpage) != 0) - goto out_fallback_unlock; - - mapping = oldpage->mapping; - index = oldpage->index; - - /* - * This is a new and locked page, it shouldn't be mapped or - * have any special flags on it - */ - if (WARN_ON(page_mapped(oldpage))) - goto out_fallback_unlock; - if (WARN_ON(page_has_private(oldpage))) - goto out_fallback_unlock; - if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage))) - goto out_fallback_unlock; - if (WARN_ON(PageMlocked(oldpage))) - goto out_fallback_unlock; - - err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL); - if (err) { - unlock_page(newpage); - return err; - } - - page_cache_get(newpage); - - if (!(buf->flags & PIPE_BUF_FLAG_LRU)) - lru_cache_add_file(newpage); - - err = 0; - spin_lock(&cs->fc->lock); - if (cs->req->aborted) - err = -ENOENT; - else - *pagep = newpage; - spin_unlock(&cs->fc->lock); - - if (err) { - unlock_page(newpage); - page_cache_release(newpage); - return err; - } - - unlock_page(oldpage); - page_cache_release(oldpage); - cs->len = 0; - - return 0; - -out_fallback_unlock: - unlock_page(newpage); -out_fallback: - cs->mapaddr = buf->ops->map(cs->pipe, buf, 1); - cs->buf = cs->mapaddr + buf->offset; - - err = lock_request(cs->fc, cs->req); - if (err) - return err; - - return 1; -} - -static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page, - unsigned offset, unsigned count) -{ - struct pipe_buffer *buf; - - if (cs->nr_segs == cs->pipe->buffers) - return -EIO; - - unlock_request(cs->fc, cs->req); - fuse_copy_finish(cs); - - buf = cs->pipebufs; - page_cache_get(page); - buf->page = page; - buf->offset = offset; - buf->len = count; - - cs->pipebufs++; - cs->nr_segs++; - cs->len = 0; - - return 0; -} - -/* - * Copy a page in the request to/from the userspace buffer. Must be - * done atomically - */ -static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep, - unsigned offset, unsigned count, int zeroing) -{ - int err; - struct page *page = *pagep; - - if (page && zeroing && count < PAGE_SIZE) - clear_highpage(page); - - while (count) { - if (cs->write && cs->pipebufs && page) { - return fuse_ref_page(cs, page, offset, count); - } else if (!cs->len) { - if (cs->move_pages && page && - offset == 0 && count == PAGE_SIZE) { - err = fuse_try_move_page(cs, pagep); - if (err <= 0) - return err; - } else { - err = fuse_copy_fill(cs); - if (err) - return err; - } - } - if (page) { - void *mapaddr = kmap_atomic(page); - void *buf = mapaddr + offset; - offset += fuse_copy_do(cs, &buf, &count); - kunmap_atomic(mapaddr); - } else - offset += fuse_copy_do(cs, NULL, &count); - } - if (page && !cs->write) - flush_dcache_page(page); - return 0; -} - -/* Copy pages in the request to/from userspace buffer */ -static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes, - int zeroing) -{ - unsigned i; - struct fuse_req *req = cs->req; - unsigned offset = req->page_offset; - unsigned count = min(nbytes, (unsigned) PAGE_SIZE - offset); - - for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) { - int err; - - err = fuse_copy_page(cs, &req->pages[i], offset, count, - zeroing); - if (err) - return err; - - nbytes -= count; - count = min(nbytes, (unsigned) PAGE_SIZE); - offset = 0; - } - return 0; -} - -/* Copy a single argument in the request to/from userspace buffer */ -static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size) -{ - while (size) { - if (!cs->len) { - int err = fuse_copy_fill(cs); - if (err) - return err; - } - fuse_copy_do(cs, &val, &size); - } - return 0; -} - -/* Copy request arguments to/from userspace buffer */ -static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs, - unsigned argpages, struct fuse_arg *args, - int zeroing) -{ - int err = 0; - unsigned i; - - for (i = 0; !err && i < numargs; i++) { - struct fuse_arg *arg = &args[i]; - if (i == numargs - 1 && argpages) - err = fuse_copy_pages(cs, arg->size, zeroing); - else - err = fuse_copy_one(cs, arg->value, arg->size); - } - return err; -} - -static int forget_pending(struct fuse_conn *fc) -{ - return fc->forget_list_head.next != NULL; -} - -static int request_pending(struct fuse_conn *fc) -{ - return !list_empty(&fc->pending) || !list_empty(&fc->interrupts) || - forget_pending(fc); -} - -/* Wait until a request is available on the pending list */ -static void request_wait(struct fuse_conn *fc) -__releases(fc->lock) -__acquires(fc->lock) -{ - DECLARE_WAITQUEUE(wait, current); - - add_wait_queue_exclusive(&fc->waitq, &wait); - while (fc->connected && !request_pending(fc)) { - set_current_state(TASK_INTERRUPTIBLE); - if (signal_pending(current)) - break; - - spin_unlock(&fc->lock); - schedule(); - spin_lock(&fc->lock); - } - set_current_state(TASK_RUNNING); - remove_wait_queue(&fc->waitq, &wait); -} - -/* - * 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_copy_state *cs, - size_t nbytes, struct fuse_req *req) -__releases(fc->lock) -{ - 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 (nbytes < reqsize) - return -EINVAL; - - 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; -} - -static struct fuse_forget_link *dequeue_forget(struct fuse_conn *fc, - unsigned max, - unsigned *countp) -{ - struct fuse_forget_link *head = fc->forget_list_head.next; - struct fuse_forget_link **newhead = &head; - unsigned count; - - for (count = 0; *newhead != NULL && count < max; count++) - newhead = &(*newhead)->next; - - fc->forget_list_head.next = *newhead; - *newhead = NULL; - if (fc->forget_list_head.next == NULL) - fc->forget_list_tail = &fc->forget_list_head; - - if (countp != NULL) - *countp = count; - - return head; -} - -static int fuse_read_single_forget(struct fuse_conn *fc, - struct fuse_copy_state *cs, - size_t nbytes) -__releases(fc->lock) -{ - int err; - struct fuse_forget_link *forget = dequeue_forget(fc, 1, NULL); - struct fuse_forget_in arg = { - .nlookup = forget->forget_one.nlookup, - }; - struct fuse_in_header ih = { - .opcode = FUSE_FORGET, - .nodeid = forget->forget_one.nodeid, - .unique = fuse_get_unique(fc), - .len = sizeof(ih) + sizeof(arg), - }; - - spin_unlock(&fc->lock); - kfree(forget); - if (nbytes < ih.len) - return -EINVAL; - - err = fuse_copy_one(cs, &ih, sizeof(ih)); - if (!err) - err = fuse_copy_one(cs, &arg, sizeof(arg)); - fuse_copy_finish(cs); - - if (err) - return err; - - return ih.len; -} - -static int fuse_read_batch_forget(struct fuse_conn *fc, - struct fuse_copy_state *cs, size_t nbytes) -__releases(fc->lock) -{ - int err; - unsigned max_forgets; - unsigned count; - struct fuse_forget_link *head; - struct fuse_batch_forget_in arg = { .count = 0 }; - struct fuse_in_header ih = { - .opcode = FUSE_BATCH_FORGET, - .unique = fuse_get_unique(fc), - .len = sizeof(ih) + sizeof(arg), - }; - - if (nbytes < ih.len) { - spin_unlock(&fc->lock); - return -EINVAL; - } - - max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one); - head = dequeue_forget(fc, max_forgets, &count); - spin_unlock(&fc->lock); - - arg.count = count; - ih.len += count * sizeof(struct fuse_forget_one); - err = fuse_copy_one(cs, &ih, sizeof(ih)); - if (!err) - err = fuse_copy_one(cs, &arg, sizeof(arg)); - - while (head) { - struct fuse_forget_link *forget = head; - - if (!err) { - err = fuse_copy_one(cs, &forget->forget_one, - sizeof(forget->forget_one)); - } - head = forget->next; - kfree(forget); - } - - fuse_copy_finish(cs); - - if (err) - return err; - - return ih.len; -} - -static int fuse_read_forget(struct fuse_conn *fc, struct fuse_copy_state *cs, - size_t nbytes) -__releases(fc->lock) -{ - if (fc->minor < 16 || fc->forget_list_head.next->next == NULL) - return fuse_read_single_forget(fc, cs, nbytes); - else - return fuse_read_batch_forget(fc, cs, nbytes); -} - -/* - * 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 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. - */ -static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, - struct fuse_copy_state *cs, size_t nbytes) -{ - int err; - struct fuse_req *req; - struct fuse_in *in; - unsigned reqsize; - - restart: - spin_lock(&fc->lock); - err = -EAGAIN; - if ((file->f_flags & O_NONBLOCK) && fc->connected && - !request_pending(fc)) - goto err_unlock; - - request_wait(fc); - err = -ENODEV; - if (!fc->connected) - goto err_unlock; - err = -ERESTARTSYS; - 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, cs, nbytes, req); - } - - if (forget_pending(fc)) { - if (list_empty(&fc->pending) || fc->forget_batch-- > 0) - return fuse_read_forget(fc, cs, nbytes); - - if (fc->forget_batch <= -8) - fc->forget_batch = 16; - } - - req = list_entry(fc->pending.next, struct fuse_req, list); - req->state = FUSE_REQ_READING; - list_move(&req->list, &fc->io); - - in = &req->in; - reqsize = in->h.len; - /* If request is too large, reply with an error and restart the read */ - if (nbytes < reqsize) { - req->out.h.error = -EIO; - /* SETXATTR is special, since it may contain too large data */ - if (in->h.opcode == FUSE_SETXATTR) - req->out.h.error = -E2BIG; - request_end(fc, req); - goto restart; - } - spin_unlock(&fc->lock); - cs->req = req; - 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(&fc->lock); - req->locked = 0; - if (req->aborted) { - request_end(fc, req); - return -ENODEV; - } - if (err) { - req->out.h.error = -EIO; - request_end(fc, req); - return err; - } - if (!req->isreply) - request_end(fc, req); - 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; - - err_unlock: - spin_unlock(&fc->lock); - return err; -} - -static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) -{ - struct fuse_copy_state cs; - struct file *file = iocb->ki_filp; - struct fuse_conn *fc = fuse_get_conn(file); - if (!fc) - return -EPERM; - - fuse_copy_init(&cs, fc, 1, iov, nr_segs); - - return fuse_dev_do_read(fc, file, &cs, iov_length(iov, nr_segs)); -} - -static int fuse_dev_pipe_buf_steal(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) -{ - return 1; -} - -static const struct pipe_buf_operations fuse_dev_pipe_buf_ops = { - .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, - .confirm = generic_pipe_buf_confirm, - .release = generic_pipe_buf_release, - .steal = fuse_dev_pipe_buf_steal, - .get = generic_pipe_buf_get, -}; - -static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, - size_t len, unsigned int flags) -{ - int ret; - int page_nr = 0; - int do_wakeup = 0; - struct pipe_buffer *bufs; - struct fuse_copy_state cs; - struct fuse_conn *fc = fuse_get_conn(in); - if (!fc) - return -EPERM; - - bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL); - if (!bufs) - return -ENOMEM; - - fuse_copy_init(&cs, fc, 1, NULL, 0); - cs.pipebufs = bufs; - cs.pipe = pipe; - ret = fuse_dev_do_read(fc, in, &cs, len); - if (ret < 0) - goto out; - - ret = 0; - pipe_lock(pipe); - - if (!pipe->readers) { - send_sig(SIGPIPE, current, 0); - if (!ret) - ret = -EPIPE; - goto out_unlock; - } - - if (pipe->nrbufs + cs.nr_segs > pipe->buffers) { - ret = -EIO; - goto out_unlock; - } - - while (page_nr < cs.nr_segs) { - int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - struct pipe_buffer *buf = pipe->bufs + newbuf; - - buf->page = bufs[page_nr].page; - buf->offset = bufs[page_nr].offset; - buf->len = bufs[page_nr].len; - buf->ops = &fuse_dev_pipe_buf_ops; - - pipe->nrbufs++; - page_nr++; - ret += buf->len; - - if (pipe->inode) - do_wakeup = 1; - } - -out_unlock: - pipe_unlock(pipe); - - if (do_wakeup) { - smp_mb(); - if (waitqueue_active(&pipe->wait)) - wake_up_interruptible(&pipe->wait); - kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); - } - -out: - for (; page_nr < cs.nr_segs; page_nr++) - page_cache_release(bufs[page_nr].page); - - kfree(bufs); - return ret; -} - -static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_poll_wakeup_out outarg; - int err = -EINVAL; - - if (size != sizeof(outarg)) - goto err; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto err; - - fuse_copy_finish(cs); - return fuse_notify_poll_wakeup(fc, &outarg); - -err: - fuse_copy_finish(cs); - return err; -} - -static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_inval_inode_out outarg; - int err = -EINVAL; - - if (size != sizeof(outarg)) - goto err; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto err; - fuse_copy_finish(cs); - - down_read(&fc->killsb); - err = -ENOENT; - if (fc->sb) { - err = fuse_reverse_inval_inode(fc->sb, outarg.ino, - outarg.off, outarg.len); - } - up_read(&fc->killsb); - return err; - -err: - fuse_copy_finish(cs); - return err; -} - -static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_inval_entry_out outarg; - int err = -ENOMEM; - char *buf; - struct qstr name; - - buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL); - if (!buf) - goto err; - - err = -EINVAL; - if (size < sizeof(outarg)) - goto err; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto err; - - err = -ENAMETOOLONG; - if (outarg.namelen > FUSE_NAME_MAX) - goto err; - - err = -EINVAL; - if (size != sizeof(outarg) + outarg.namelen + 1) - goto err; - - name.name = buf; - name.len = outarg.namelen; - err = fuse_copy_one(cs, buf, outarg.namelen + 1); - if (err) - goto err; - fuse_copy_finish(cs); - buf[outarg.namelen] = 0; - name.hash = full_name_hash(name.name, name.len); - - down_read(&fc->killsb); - err = -ENOENT; - if (fc->sb) - err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name); - up_read(&fc->killsb); - kfree(buf); - return err; - -err: - kfree(buf); - fuse_copy_finish(cs); - return err; -} - -static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_delete_out outarg; - int err = -ENOMEM; - char *buf; - struct qstr name; - - buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL); - if (!buf) - goto err; - - err = -EINVAL; - if (size < sizeof(outarg)) - goto err; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto err; - - err = -ENAMETOOLONG; - if (outarg.namelen > FUSE_NAME_MAX) - goto err; - - err = -EINVAL; - if (size != sizeof(outarg) + outarg.namelen + 1) - goto err; - - name.name = buf; - name.len = outarg.namelen; - err = fuse_copy_one(cs, buf, outarg.namelen + 1); - if (err) - goto err; - fuse_copy_finish(cs); - buf[outarg.namelen] = 0; - name.hash = full_name_hash(name.name, name.len); - - down_read(&fc->killsb); - err = -ENOENT; - if (fc->sb) - err = fuse_reverse_inval_entry(fc->sb, outarg.parent, - outarg.child, &name); - up_read(&fc->killsb); - kfree(buf); - return err; - -err: - kfree(buf); - fuse_copy_finish(cs); - return err; -} - -static int fuse_notify_store(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_store_out outarg; - struct inode *inode; - struct address_space *mapping; - u64 nodeid; - int err; - pgoff_t index; - unsigned int offset; - unsigned int num; - loff_t file_size; - loff_t end; - - err = -EINVAL; - if (size < sizeof(outarg)) - goto out_finish; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto out_finish; - - err = -EINVAL; - if (size - sizeof(outarg) != outarg.size) - goto out_finish; - - nodeid = outarg.nodeid; - - down_read(&fc->killsb); - - err = -ENOENT; - if (!fc->sb) - goto out_up_killsb; - - inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid); - if (!inode) - goto out_up_killsb; - - mapping = inode->i_mapping; - index = outarg.offset >> PAGE_CACHE_SHIFT; - offset = outarg.offset & ~PAGE_CACHE_MASK; - file_size = i_size_read(inode); - end = outarg.offset + outarg.size; - if (end > file_size) { - file_size = end; - fuse_write_update_size(inode, file_size); - } - - num = outarg.size; - while (num) { - struct page *page; - unsigned int this_num; - - err = -ENOMEM; - page = find_or_create_page(mapping, index, - mapping_gfp_mask(mapping)); - if (!page) - goto out_iput; - - this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset); - err = fuse_copy_page(cs, &page, offset, this_num, 0); - if (!err && offset == 0 && (num != 0 || file_size == end)) - SetPageUptodate(page); - unlock_page(page); - page_cache_release(page); - - if (err) - goto out_iput; - - num -= this_num; - offset = 0; - index++; - } - - err = 0; - -out_iput: - iput(inode); -out_up_killsb: - up_read(&fc->killsb); -out_finish: - fuse_copy_finish(cs); - return err; -} - -static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req) -{ - release_pages(req->pages, req->num_pages, 0); -} - -static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, - struct fuse_notify_retrieve_out *outarg) -{ - int err; - struct address_space *mapping = inode->i_mapping; - struct fuse_req *req; - pgoff_t index; - loff_t file_size; - unsigned int num; - unsigned int offset; - size_t total_len = 0; - - req = fuse_get_req(fc); - if (IS_ERR(req)) - return PTR_ERR(req); - - offset = outarg->offset & ~PAGE_CACHE_MASK; - - req->in.h.opcode = FUSE_NOTIFY_REPLY; - req->in.h.nodeid = outarg->nodeid; - req->in.numargs = 2; - req->in.argpages = 1; - req->page_offset = offset; - req->end = fuse_retrieve_end; - - index = outarg->offset >> PAGE_CACHE_SHIFT; - file_size = i_size_read(inode); - num = outarg->size; - if (outarg->offset > file_size) - num = 0; - else if (outarg->offset + num > file_size) - num = file_size - outarg->offset; - - while (num && req->num_pages < FUSE_MAX_PAGES_PER_REQ) { - struct page *page; - unsigned int this_num; - - page = find_get_page(mapping, index); - if (!page) - break; - - this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset); - req->pages[req->num_pages] = page; - req->num_pages++; - - num -= this_num; - total_len += this_num; - index++; - } - req->misc.retrieve_in.offset = outarg->offset; - req->misc.retrieve_in.size = total_len; - req->in.args[0].size = sizeof(req->misc.retrieve_in); - req->in.args[0].value = &req->misc.retrieve_in; - req->in.args[1].size = total_len; - - err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique); - if (err) - fuse_retrieve_end(fc, req); - - return err; -} - -static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size, - struct fuse_copy_state *cs) -{ - struct fuse_notify_retrieve_out outarg; - struct inode *inode; - int err; - - err = -EINVAL; - if (size != sizeof(outarg)) - goto copy_finish; - - err = fuse_copy_one(cs, &outarg, sizeof(outarg)); - if (err) - goto copy_finish; - - fuse_copy_finish(cs); - - down_read(&fc->killsb); - err = -ENOENT; - if (fc->sb) { - u64 nodeid = outarg.nodeid; - - inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid); - if (inode) { - err = fuse_retrieve(fc, inode, &outarg); - iput(inode); - } - } - up_read(&fc->killsb); - - return err; - -copy_finish: - fuse_copy_finish(cs); - return err; -} - -static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code, - unsigned int size, struct fuse_copy_state *cs) -{ - switch (code) { - case FUSE_NOTIFY_POLL: - return fuse_notify_poll(fc, size, cs); - - case FUSE_NOTIFY_INVAL_INODE: - return fuse_notify_inval_inode(fc, size, cs); - - case FUSE_NOTIFY_INVAL_ENTRY: - return fuse_notify_inval_entry(fc, size, cs); - - case FUSE_NOTIFY_STORE: - return fuse_notify_store(fc, size, cs); - - case FUSE_NOTIFY_RETRIEVE: - return fuse_notify_retrieve(fc, size, cs); - - case FUSE_NOTIFY_DELETE: - return fuse_notify_delete(fc, size, cs); - - default: - fuse_copy_finish(cs); - return -EINVAL; - } -} - -/* Look up request on processing list by unique ID */ -static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique) -{ - struct list_head *entry; - - list_for_each(entry, &fc->processing) { - struct fuse_req *req; - req = list_entry(entry, struct fuse_req, list); - if (req->in.h.unique == unique || req->intr_unique == unique) - return req; - } - return NULL; -} - -static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out, - unsigned nbytes) -{ - unsigned reqsize = sizeof(struct fuse_out_header); - - if (out->h.error) - return nbytes != reqsize ? -EINVAL : 0; - - reqsize += len_args(out->numargs, out->args); - - if (reqsize < nbytes || (reqsize > nbytes && !out->argvar)) - return -EINVAL; - else if (reqsize > nbytes) { - struct fuse_arg *lastarg = &out->args[out->numargs-1]; - unsigned diffsize = reqsize - nbytes; - if (diffsize > lastarg->size) - return -EINVAL; - lastarg->size -= diffsize; - } - return fuse_copy_args(cs, out->numargs, out->argpages, out->args, - out->page_zeroing); -} - -/* - * Write a single reply to a request. First the header is copied from - * the write buffer. The request is then searched on the processing - * list by the unique ID found in the header. If found, then remove - * it from the list and copy the rest of the buffer to the request. - * The request is finished by calling request_end() - */ -static ssize_t fuse_dev_do_write(struct fuse_conn *fc, - struct fuse_copy_state *cs, size_t nbytes) -{ - int err; - struct fuse_req *req; - struct fuse_out_header oh; - - if (nbytes < sizeof(struct fuse_out_header)) - return -EINVAL; - - err = fuse_copy_one(cs, &oh, sizeof(oh)); - if (err) - goto err_finish; - - err = -EINVAL; - if (oh.len != nbytes) - goto err_finish; - - /* - * Zero oh.unique indicates unsolicited notification message - * and error contains notification code. - */ - if (!oh.unique) { - err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs); - return err ? err : nbytes; - } - - err = -EINVAL; - if (oh.error <= -1000 || oh.error > 0) - goto err_finish; - - spin_lock(&fc->lock); - err = -ENOENT; - if (!fc->connected) - goto err_unlock; - - req = request_find(fc, oh.unique); - if (!req) - goto err_unlock; - - 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; - cs->req = req; - if (!req->out.page_replace) - cs->move_pages = 0; - spin_unlock(&fc->lock); - - err = copy_out_args(cs, &req->out, nbytes); - fuse_copy_finish(cs); - - spin_lock(&fc->lock); - req->locked = 0; - if (!err) { - if (req->aborted) - err = -ENOENT; - } else if (!req->aborted) - req->out.h.error = -EIO; - request_end(fc, req); - - return err ? err : nbytes; - - err_unlock: - spin_unlock(&fc->lock); - err_finish: - fuse_copy_finish(cs); - return err; -} - -static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) -{ - struct fuse_copy_state cs; - struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp); - if (!fc) - return -EPERM; - - fuse_copy_init(&cs, fc, 0, iov, nr_segs); - - return fuse_dev_do_write(fc, &cs, iov_length(iov, nr_segs)); -} - -static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, - struct file *out, loff_t *ppos, - size_t len, unsigned int flags) -{ - unsigned nbuf; - unsigned idx; - struct pipe_buffer *bufs; - struct fuse_copy_state cs; - struct fuse_conn *fc; - size_t rem; - ssize_t ret; - - fc = fuse_get_conn(out); - if (!fc) - return -EPERM; - - bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL); - if (!bufs) - return -ENOMEM; - - pipe_lock(pipe); - nbuf = 0; - rem = 0; - for (idx = 0; idx < pipe->nrbufs && rem < len; idx++) - rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len; - - ret = -EINVAL; - if (rem < len) { - pipe_unlock(pipe); - goto out; - } - - rem = len; - while (rem) { - struct pipe_buffer *ibuf; - struct pipe_buffer *obuf; - - BUG_ON(nbuf >= pipe->buffers); - BUG_ON(!pipe->nrbufs); - ibuf = &pipe->bufs[pipe->curbuf]; - obuf = &bufs[nbuf]; - - if (rem >= ibuf->len) { - *obuf = *ibuf; - ibuf->ops = NULL; - pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); - pipe->nrbufs--; - } else { - ibuf->ops->get(pipe, ibuf); - *obuf = *ibuf; - obuf->flags &= ~PIPE_BUF_FLAG_GIFT; - obuf->len = rem; - ibuf->offset += obuf->len; - ibuf->len -= obuf->len; - } - nbuf++; - rem -= obuf->len; - } - pipe_unlock(pipe); - - fuse_copy_init(&cs, fc, 0, NULL, nbuf); - cs.pipebufs = bufs; - cs.pipe = pipe; - - if (flags & SPLICE_F_MOVE) - cs.move_pages = 1; - - ret = fuse_dev_do_write(fc, &cs, len); - - for (idx = 0; idx < nbuf; idx++) { - struct pipe_buffer *buf = &bufs[idx]; - buf->ops->release(pipe, buf); - } -out: - kfree(bufs); - return ret; -} - -static unsigned fuse_dev_poll(struct file *file, poll_table *wait) -{ - unsigned mask = POLLOUT | POLLWRNORM; - struct fuse_conn *fc = fuse_get_conn(file); - if (!fc) - return POLLERR; - - poll_wait(file, &fc->waitq, wait); - - spin_lock(&fc->lock); - if (!fc->connected) - mask = POLLERR; - else if (request_pending(fc)) - mask |= POLLIN | POLLRDNORM; - spin_unlock(&fc->lock); - - return mask; -} - -/* - * Abort all requests on the given list (pending or processing) - * - * This function releases and reacquires fc->lock - */ -static void end_requests(struct fuse_conn *fc, struct list_head *head) -__releases(fc->lock) -__acquires(fc->lock) -{ - while (!list_empty(head)) { - struct fuse_req *req; - req = list_entry(head->next, struct fuse_req, list); - req->out.h.error = -ECONNABORTED; - request_end(fc, req); - spin_lock(&fc->lock); - } -} - -/* - * Abort requests under I/O - * - * 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. - * - * If the request is asynchronous, then the end function needs to be - * called after waiting for the request to be unlocked (if it was - * locked). - */ -static void end_io_requests(struct fuse_conn *fc) -__releases(fc->lock) -__acquires(fc->lock) -{ - while (!list_empty(&fc->io)) { - struct fuse_req *req = - list_entry(fc->io.next, struct fuse_req, list); - void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; - - req->aborted = 1; - req->out.h.error = -ECONNABORTED; - req->state = FUSE_REQ_FINISHED; - list_del_init(&req->list); - wake_up(&req->waitq); - if (end) { - req->end = NULL; - __fuse_get_request(req); - spin_unlock(&fc->lock); - wait_event(req->waitq, !req->locked); - end(fc, req); - fuse_put_request(fc, req); - spin_lock(&fc->lock); - } - } -} - -static void end_queued_requests(struct fuse_conn *fc) -__releases(fc->lock) -__acquires(fc->lock) -{ - fc->max_background = UINT_MAX; - flush_bg_queue(fc); - end_requests(fc, &fc->pending); - end_requests(fc, &fc->processing); - while (forget_pending(fc)) - kfree(dequeue_forget(fc, 1, NULL)); -} - -static void end_polls(struct fuse_conn *fc) -{ - struct rb_node *p; - - p = rb_first(&fc->polled_files); - - while (p) { - struct fuse_file *ff; - ff = rb_entry(p, struct fuse_file, polled_node); - wake_up_interruptible_all(&ff->poll_wait); - - p = rb_next(p); - } -} - -/* - * Abort all requests. - * - * Emergency exit in case of a malicious or accidental deadlock, or - * just a hung filesystem. - * - * The same effect is usually achievable through killing the - * filesystem daemon and all users of the filesystem. The exception - * is the combination of an asynchronous request and the tricky - * deadlock (see Documentation/filesystems/fuse.txt). - * - * During the aborting, progression of requests from the pending and - * processing lists onto the io list, and progression of new requests - * 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->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_queued_requests(fc); - end_polls(fc); - wake_up_all(&fc->waitq); - wake_up_all(&fc->blocked_waitq); - kill_fasync(&fc->fasync, SIGIO, POLL_IN); - } - spin_unlock(&fc->lock); -} -EXPORT_SYMBOL_GPL(fuse_abort_conn); - -int fuse_dev_release(struct inode *inode, struct file *file) -{ - struct fuse_conn *fc = fuse_get_conn(file); - if (fc) { - spin_lock(&fc->lock); - fc->connected = 0; - fc->blocked = 0; - end_queued_requests(fc); - end_polls(fc); - wake_up_all(&fc->blocked_waitq); - spin_unlock(&fc->lock); - fuse_conn_put(fc); - } - - return 0; -} -EXPORT_SYMBOL_GPL(fuse_dev_release); - -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, - .read = do_sync_read, - .aio_read = fuse_dev_read, - .splice_read = fuse_dev_splice_read, - .write = do_sync_write, - .aio_write = fuse_dev_write, - .splice_write = fuse_dev_splice_write, - .poll = fuse_dev_poll, - .release = fuse_dev_release, - .fasync = fuse_dev_fasync, -}; -EXPORT_SYMBOL_GPL(fuse_dev_operations); - -static struct miscdevice fuse_miscdevice = { - .minor = FUSE_MINOR, - .name = "fuse", - .fops = &fuse_dev_operations, -}; - -int __init fuse_dev_init(void) -{ - int err = -ENOMEM; - fuse_req_cachep = kmem_cache_create("fuse_request", - sizeof(struct fuse_req), - 0, 0, NULL); - if (!fuse_req_cachep) - goto out; - - err = misc_register(&fuse_miscdevice); - if (err) - goto out_cache_clean; - - return 0; - - out_cache_clean: - kmem_cache_destroy(fuse_req_cachep); - out: - return err; -} - -void fuse_dev_cleanup(void) -{ - misc_deregister(&fuse_miscdevice); - kmem_cache_destroy(fuse_req_cachep); -} |