diff options
| -rw-r--r-- | drivers/block/loop.c | 11 | ||||
| -rw-r--r-- | fs/coda/file.c | 9 | ||||
| -rw-r--r-- | fs/pipe.c | 14 | ||||
| -rw-r--r-- | fs/read_write.c | 7 | ||||
| -rw-r--r-- | fs/splice.c | 120 | ||||
| -rw-r--r-- | include/linux/fs.h | 2 | ||||
| -rw-r--r-- | include/linux/pipe_fs_i.h | 1 |
7 files changed, 140 insertions, 24 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 9ca4bb01465..801f4ab8330 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -709,10 +709,6 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, if (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode)) goto out_putf; - /* new backing store needs to support loop (eg splice_read) */ - if (!inode->i_fop->splice_read) - goto out_putf; - /* size of the new backing store needs to be the same */ if (get_loop_size(lo, file) != get_loop_size(lo, old_file)) goto out_putf; @@ -788,12 +784,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, error = -EINVAL; if (S_ISREG(inode->i_mode) || S_ISBLK(inode->i_mode)) { const struct address_space_operations *aops = mapping->a_ops; - /* - * If we can't read - sorry. If we only can't write - well, - * it's going to be read-only. - */ - if (!file->f_op->splice_read) - goto out_putf; + if (aops->write_begin) lo_flags |= LO_FLAGS_USE_AOPS; if (!(lo_flags & LO_FLAGS_USE_AOPS) && !file->f_op->write) diff --git a/fs/coda/file.c b/fs/coda/file.c index 6a347fbc998..ffd42815fda 100644 --- a/fs/coda/file.c +++ b/fs/coda/file.c @@ -47,6 +47,8 @@ coda_file_splice_read(struct file *coda_file, loff_t *ppos, struct pipe_inode_info *pipe, size_t count, unsigned int flags) { + ssize_t (*splice_read)(struct file *, loff_t *, + struct pipe_inode_info *, size_t, unsigned int); struct coda_file_info *cfi; struct file *host_file; @@ -54,10 +56,11 @@ coda_file_splice_read(struct file *coda_file, loff_t *ppos, BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); host_file = cfi->cfi_container; - if (!host_file->f_op || !host_file->f_op->splice_read) - return -EINVAL; + splice_read = host_file->f_op->splice_read; + if (!splice_read) + splice_read = default_file_splice_read; - return host_file->f_op->splice_read(host_file, ppos, pipe, count,flags); + return splice_read(host_file, ppos, pipe, count, flags); } static ssize_t diff --git a/fs/pipe.c b/fs/pipe.c index 13414ec45b8..f7dd21ad85a 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -302,6 +302,20 @@ int generic_pipe_buf_confirm(struct pipe_inode_info *info, return 0; } +/** + * generic_pipe_buf_release - put a reference to a &struct pipe_buffer + * @pipe: the pipe that the buffer belongs to + * @buf: the buffer to put a reference to + * + * Description: + * This function releases a reference to @buf. + */ +void generic_pipe_buf_release(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ + page_cache_release(buf->page); +} + static const struct pipe_buf_operations anon_pipe_buf_ops = { .can_merge = 1, .map = generic_pipe_buf_map, diff --git a/fs/read_write.c b/fs/read_write.c index 9d1e76bb9ee..6c8c55dec2b 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -805,12 +805,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, goto out; if (!(in_file->f_mode & FMODE_READ)) goto fput_in; - retval = -EINVAL; - in_inode = in_file->f_path.dentry->d_inode; - if (!in_inode) - goto fput_in; - if (!in_file->f_op || !in_file->f_op->splice_read) - goto fput_in; retval = -ESPIPE; if (!ppos) ppos = &in_file->f_pos; @@ -834,6 +828,7 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, retval = -EINVAL; if (!out_file->f_op || !out_file->f_op->sendpage) goto fput_out; + in_inode = in_file->f_path.dentry->d_inode; out_inode = out_file->f_path.dentry->d_inode; retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); if (retval < 0) diff --git a/fs/splice.c b/fs/splice.c index e405cf552f5..3bd9cb21b38 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -507,9 +507,116 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, return ret; } - EXPORT_SYMBOL(generic_file_splice_read); +static const struct pipe_buf_operations default_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 = generic_pipe_buf_steal, + .get = generic_pipe_buf_get, +}; + +static ssize_t kernel_readv(struct file *file, const struct iovec *vec, + unsigned long vlen, loff_t offset) +{ + mm_segment_t old_fs; + loff_t pos = offset; + ssize_t res; + + old_fs = get_fs(); + set_fs(get_ds()); + /* The cast to a user pointer is valid due to the set_fs() */ + res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos); + set_fs(old_fs); + + return res; +} + +ssize_t default_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + unsigned int nr_pages; + unsigned int nr_freed; + size_t offset; + struct page *pages[PIPE_BUFFERS]; + struct partial_page partial[PIPE_BUFFERS]; + struct iovec vec[PIPE_BUFFERS]; + pgoff_t index; + ssize_t res; + size_t this_len; + int error; + int i; + struct splice_pipe_desc spd = { + .pages = pages, + .partial = partial, + .flags = flags, + .ops = &default_pipe_buf_ops, + .spd_release = spd_release_page, + }; + + index = *ppos >> PAGE_CACHE_SHIFT; + offset = *ppos & ~PAGE_CACHE_MASK; + nr_pages = (len + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; + + for (i = 0; i < nr_pages && i < PIPE_BUFFERS && len; i++) { + struct page *page; + + page = alloc_page(GFP_HIGHUSER); + error = -ENOMEM; + if (!page) + goto err; + + this_len = min_t(size_t, len, PAGE_CACHE_SIZE - offset); + vec[i].iov_base = (void __user *) kmap(page); + vec[i].iov_len = this_len; + pages[i] = page; + spd.nr_pages++; + len -= this_len; + offset = 0; + } + + res = kernel_readv(in, vec, spd.nr_pages, *ppos); + if (res < 0) + goto err; + + error = 0; + if (!res) + goto err; + + nr_freed = 0; + for (i = 0; i < spd.nr_pages; i++) { + kunmap(pages[i]); + this_len = min_t(size_t, vec[i].iov_len, res); + partial[i].offset = 0; + partial[i].len = this_len; + if (!this_len) { + __free_page(pages[i]); + pages[i] = NULL; + nr_freed++; + } + res -= this_len; + } + spd.nr_pages -= nr_freed; + + res = splice_to_pipe(pipe, &spd); + if (res > 0) + *ppos += res; + + return res; + +err: + for (i = 0; i < spd.nr_pages; i++) { + kunmap(pages[i]); + __free_page(pages[i]); + } + return error; +} +EXPORT_SYMBOL(default_file_splice_read); + /* * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' * using sendpage(). Return the number of bytes sent. @@ -933,11 +1040,10 @@ static long do_splice_to(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { + ssize_t (*splice_read)(struct file *, loff_t *, + struct pipe_inode_info *, size_t, unsigned int); int ret; - if (unlikely(!in->f_op || !in->f_op->splice_read)) - return -EINVAL; - if (unlikely(!(in->f_mode & FMODE_READ))) return -EBADF; @@ -945,7 +1051,11 @@ static long do_splice_to(struct file *in, loff_t *ppos, if (unlikely(ret < 0)) return ret; - return in->f_op->splice_read(in, ppos, pipe, len, flags); + splice_read = in->f_op->splice_read; + if (!splice_read) + splice_read = default_file_splice_read; + + return splice_read(in, ppos, pipe, len, flags); } /** diff --git a/include/linux/fs.h b/include/linux/fs.h index 5bed436f435..d926c2bea16 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2204,6 +2204,8 @@ extern int generic_segment_checks(const struct iovec *iov, /* fs/splice.c */ extern ssize_t generic_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); +extern ssize_t default_file_splice_read(struct file *, loff_t *, + struct pipe_inode_info *, size_t, unsigned int); extern ssize_t generic_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index c8f038554e8..b43a9e03905 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -152,5 +152,6 @@ void generic_pipe_buf_unmap(struct pipe_inode_info *, struct pipe_buffer *, void void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); +void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); #endif |