X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffuse%2Ffile.c;h=67ff2c6a8f6309bc09746a65d29b8d55f0a90bb5;hb=996abf053eec4d67136be8b911bbaaf989cfb99c;hp=f0f0f278b4eae6cc150daa07f6ad220131d222f4;hpb=854512ec358f291bcadd7daea10d6bf3704933de;p=linux-2.6 diff --git a/fs/fuse/file.c b/fs/fuse/file.c index f0f0f278b4..67ff2c6a8f 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -363,7 +363,7 @@ static int fuse_fsync(struct file *file, struct dentry *de, int datasync) void fuse_read_fill(struct fuse_req *req, struct file *file, struct inode *inode, loff_t pos, size_t count, int opcode) { - struct fuse_read_in *inarg = &req->misc.read_in; + struct fuse_read_in *inarg = &req->misc.read.in; struct fuse_file *ff = file->private_data; inarg->fh = ff->fh; @@ -389,7 +389,7 @@ static size_t fuse_send_read(struct fuse_req *req, struct file *file, fuse_read_fill(req, file, inode, pos, count, FUSE_READ); if (owner != NULL) { - struct fuse_read_in *inarg = &req->misc.read_in; + struct fuse_read_in *inarg = &req->misc.read.in; inarg->read_flags |= FUSE_READ_LOCKOWNER; inarg->lock_owner = fuse_lock_owner_id(fc, owner); @@ -398,11 +398,29 @@ static size_t fuse_send_read(struct fuse_req *req, struct file *file, return req->out.args[0].size; } +static void fuse_read_update_size(struct inode *inode, loff_t size, + u64 attr_ver) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_inode *fi = get_fuse_inode(inode); + + spin_lock(&fc->lock); + if (attr_ver == fi->attr_version && size < inode->i_size) { + fi->attr_version = ++fc->attr_version; + i_size_write(inode, size); + } + spin_unlock(&fc->lock); +} + static int fuse_readpage(struct file *file, struct page *page) { struct inode *inode = page->mapping->host; struct fuse_conn *fc = get_fuse_conn(inode); struct fuse_req *req; + size_t num_read; + loff_t pos = page_offset(page); + size_t count = PAGE_CACHE_SIZE; + u64 attr_ver; int err; err = -EIO; @@ -421,15 +439,25 @@ static int fuse_readpage(struct file *file, struct page *page) if (IS_ERR(req)) goto out; + attr_ver = fuse_get_attr_version(fc); + req->out.page_zeroing = 1; req->num_pages = 1; req->pages[0] = page; - fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE, - NULL); + num_read = fuse_send_read(req, file, inode, pos, count, NULL); err = req->out.h.error; fuse_put_request(fc, req); - if (!err) + + if (!err) { + /* + * Short read means EOF. If file size is larger, truncate it + */ + if (num_read < count) + fuse_read_update_size(inode, pos + num_read, attr_ver); + SetPageUptodate(page); + } + fuse_invalidate_attr(inode); /* atime changed */ out: unlock_page(page); @@ -439,8 +467,19 @@ static int fuse_readpage(struct file *file, struct page *page) static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) { int i; + size_t count = req->misc.read.in.size; + size_t num_read = req->out.args[0].size; + struct inode *inode = req->pages[0]->mapping->host; + + /* + * Short read means EOF. If file size is larger, truncate it + */ + if (!req->out.h.error && num_read < count) { + loff_t pos = page_offset(req->pages[0]) + num_read; + fuse_read_update_size(inode, pos, req->misc.read.attr_ver); + } - fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */ + fuse_invalidate_attr(inode); /* atime changed */ for (i = 0; i < req->num_pages; i++) { struct page *page = req->pages[i]; @@ -463,6 +502,7 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file, size_t count = req->num_pages << PAGE_CACHE_SHIFT; req->out.page_zeroing = 1; fuse_read_fill(req, file, inode, pos, count, FUSE_READ); + req->misc.read.attr_ver = fuse_get_attr_version(fc); if (fc->async_read) { struct fuse_file *ff = file->private_data; req->ff = fuse_file_get(ff); @@ -677,6 +717,200 @@ static int fuse_write_end(struct file *file, struct address_space *mapping, return res; } +static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, + struct inode *inode, loff_t pos, + size_t count) +{ + size_t res; + unsigned offset; + unsigned i; + + for (i = 0; i < req->num_pages; i++) + fuse_wait_on_page_writeback(inode, req->pages[i]->index); + + res = fuse_send_write(req, file, inode, pos, count, NULL); + + offset = req->page_offset; + count = res; + for (i = 0; i < req->num_pages; i++) { + struct page *page = req->pages[i]; + + if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE) + SetPageUptodate(page); + + if (count > PAGE_CACHE_SIZE - offset) + count -= PAGE_CACHE_SIZE - offset; + else + count = 0; + offset = 0; + + unlock_page(page); + page_cache_release(page); + } + + return res; +} + +static ssize_t fuse_fill_write_pages(struct fuse_req *req, + struct address_space *mapping, + struct iov_iter *ii, loff_t pos) +{ + struct fuse_conn *fc = get_fuse_conn(mapping->host); + unsigned offset = pos & (PAGE_CACHE_SIZE - 1); + size_t count = 0; + int err; + + req->page_offset = offset; + + do { + size_t tmp; + struct page *page; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset, + iov_iter_count(ii)); + + bytes = min_t(size_t, bytes, fc->max_write - count); + + again: + err = -EFAULT; + if (iov_iter_fault_in_readable(ii, bytes)) + break; + + err = -ENOMEM; + page = __grab_cache_page(mapping, index); + if (!page) + break; + + pagefault_disable(); + tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes); + pagefault_enable(); + flush_dcache_page(page); + + if (!tmp) { + unlock_page(page); + page_cache_release(page); + bytes = min(bytes, iov_iter_single_seg_count(ii)); + goto again; + } + + err = 0; + req->pages[req->num_pages] = page; + req->num_pages++; + + iov_iter_advance(ii, tmp); + count += tmp; + pos += tmp; + offset += tmp; + if (offset == PAGE_CACHE_SIZE) + offset = 0; + + if (!fc->big_writes) + break; + } while (iov_iter_count(ii) && count < fc->max_write && + req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0); + + return count > 0 ? count : err; +} + +static ssize_t fuse_perform_write(struct file *file, + struct address_space *mapping, + struct iov_iter *ii, loff_t pos) +{ + struct inode *inode = mapping->host; + struct fuse_conn *fc = get_fuse_conn(inode); + int err = 0; + ssize_t res = 0; + + if (is_bad_inode(inode)) + return -EIO; + + do { + struct fuse_req *req; + ssize_t count; + + req = fuse_get_req(fc); + if (IS_ERR(req)) { + err = PTR_ERR(req); + break; + } + + count = fuse_fill_write_pages(req, mapping, ii, pos); + if (count <= 0) { + err = count; + } else { + size_t num_written; + + num_written = fuse_send_write_pages(req, file, inode, + pos, count); + err = req->out.h.error; + if (!err) { + res += num_written; + pos += num_written; + + /* break out of the loop on short write */ + if (num_written != count) + err = -EIO; + } + } + fuse_put_request(fc, req); + } while (!err && iov_iter_count(ii)); + + if (res > 0) + fuse_write_update_size(inode, pos); + + fuse_invalidate_attr(inode); + + return res > 0 ? res : err; +} + +static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + struct file *file = iocb->ki_filp; + struct address_space *mapping = file->f_mapping; + size_t count = 0; + ssize_t written = 0; + struct inode *inode = mapping->host; + ssize_t err; + struct iov_iter i; + + WARN_ON(iocb->ki_pos != pos); + + err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ); + if (err) + return err; + + mutex_lock(&inode->i_mutex); + vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); + + /* We can write back this queue in page reclaim */ + current->backing_dev_info = mapping->backing_dev_info; + + err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); + if (err) + goto out; + + if (count == 0) + goto out; + + err = remove_suid(file->f_path.dentry); + if (err) + goto out; + + file_update_time(file); + + iov_iter_init(&i, iov, nr_segs, count, 0); + written = fuse_perform_write(file, mapping, &i, pos); + if (written >= 0) + iocb->ki_pos = pos + written; + +out: + current->backing_dev_info = NULL; + mutex_unlock(&inode->i_mutex); + + return written ? written : err; +} + static void fuse_release_user_pages(struct fuse_req *req, int write) { unsigned i; @@ -702,7 +936,7 @@ static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf, nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; - npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ); + npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ); down_read(¤t->mm->mmap_sem); npages = get_user_pages(current, current->mm, user_addr, npages, write, 0, req->pages, NULL); @@ -734,14 +968,15 @@ static ssize_t fuse_direct_io(struct file *file, const char __user *buf, while (count) { size_t nres; - size_t nbytes = min(count, nmax); - int err = fuse_get_user_pages(req, buf, nbytes, !write); + size_t nbytes_limit = min(count, nmax); + size_t nbytes; + int err = fuse_get_user_pages(req, buf, nbytes_limit, !write); if (err) { res = err; break; } nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset; - nbytes = min(count, nbytes); + nbytes = min(nbytes_limit, nbytes); if (write) nres = fuse_send_write(req, file, inode, pos, nbytes, current->files); @@ -1106,6 +1341,11 @@ static int fuse_setlk(struct file *file, struct file_lock *fl, int flock) pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; int err; + if (fl->fl_lmops && fl->fl_lmops->fl_grant) { + /* NLM needs asynchronous locks, which we don't support yet */ + return -ENOLCK; + } + /* Unlock on close is handled by the flush method */ if (fl->fl_flags & FL_CLOSE) return 0; @@ -1130,7 +1370,9 @@ static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) struct fuse_conn *fc = get_fuse_conn(inode); int err; - if (cmd == F_GETLK) { + if (cmd == F_CANCELLK) { + err = 0; + } else if (cmd == F_GETLK) { if (fc->no_lock) { posix_test_lock(file, fl); err = 0; @@ -1138,7 +1380,7 @@ static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) err = fuse_getlk(file, fl); } else { if (fc->no_lock) - err = posix_lock_file_wait(file, fl); + err = posix_lock_file(file, fl, NULL); else err = fuse_setlk(file, fl, 0); } @@ -1198,12 +1440,37 @@ static sector_t fuse_bmap(struct address_space *mapping, sector_t block) return err ? 0 : outarg.block; } +static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin) +{ + loff_t retval; + struct inode *inode = file->f_path.dentry->d_inode; + + mutex_lock(&inode->i_mutex); + switch (origin) { + case SEEK_END: + offset += i_size_read(inode); + break; + case SEEK_CUR: + offset += file->f_pos; + } + retval = -EINVAL; + if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { + if (offset != file->f_pos) { + file->f_pos = offset; + file->f_version = 0; + } + retval = offset; + } + mutex_unlock(&inode->i_mutex); + return retval; +} + static const struct file_operations fuse_file_operations = { - .llseek = generic_file_llseek, + .llseek = fuse_file_llseek, .read = do_sync_read, .aio_read = fuse_file_aio_read, .write = do_sync_write, - .aio_write = generic_file_aio_write, + .aio_write = fuse_file_aio_write, .mmap = fuse_file_mmap, .open = fuse_open, .flush = fuse_flush, @@ -1215,7 +1482,7 @@ static const struct file_operations fuse_file_operations = { }; static const struct file_operations fuse_direct_io_file_operations = { - .llseek = generic_file_llseek, + .llseek = fuse_file_llseek, .read = fuse_direct_read, .write = fuse_direct_write, .open = fuse_open,