diff options
author | David Woodhouse <dwmw2@infradead.org> | 2007-07-23 10:20:10 +0100 |
---|---|---|
committer | David Woodhouse <dwmw2@infradead.org> | 2007-07-23 10:20:10 +0100 |
commit | 39fe5434cb9de5da40510028b17b96bc4eb312b3 (patch) | |
tree | 7a02a317b9ad57da51ca99887c119e779ccf3f13 /fs/splice.c | |
parent | 0fc72b81d3111d114ab378935b1cf07680ca1289 (diff) | |
parent | f695baf2df9e0413d3521661070103711545207a (diff) |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Diffstat (limited to 'fs/splice.c')
-rw-r--r-- | fs/splice.c | 83 |
1 files changed, 39 insertions, 44 deletions
diff --git a/fs/splice.c b/fs/splice.c index ed2ce995475c..0a0973218084 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -28,6 +28,7 @@ #include <linux/module.h> #include <linux/syscalls.h> #include <linux/uio.h> +#include <linux/security.h> /* * Attempt to steal a page from a pipe buffer. This should perhaps go into @@ -264,7 +265,7 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, unsigned int flags) { struct address_space *mapping = in->f_mapping; - unsigned int loff, nr_pages; + unsigned int loff, nr_pages, req_pages; struct page *pages[PIPE_BUFFERS]; struct partial_page partial[PIPE_BUFFERS]; struct page *page; @@ -280,28 +281,24 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, index = *ppos >> PAGE_CACHE_SHIFT; loff = *ppos & ~PAGE_CACHE_MASK; - nr_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - - if (nr_pages > PIPE_BUFFERS) - nr_pages = PIPE_BUFFERS; - - /* - * Don't try to 2nd guess the read-ahead logic, call into - * page_cache_readahead() like the page cache reads would do. - */ - page_cache_readahead(mapping, &in->f_ra, in, index, nr_pages); + req_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; + nr_pages = min(req_pages, (unsigned)PIPE_BUFFERS); /* * Lookup the (hopefully) full range of pages we need. */ spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, pages); + index += spd.nr_pages; /* * If find_get_pages_contig() returned fewer pages than we needed, - * allocate the rest and fill in the holes. + * readahead/allocate the rest and fill in the holes. */ + if (spd.nr_pages < nr_pages) + page_cache_sync_readahead(mapping, &in->f_ra, in, + index, req_pages - spd.nr_pages); + error = 0; - index += spd.nr_pages; while (spd.nr_pages < nr_pages) { /* * Page could be there, find_get_pages_contig() breaks on @@ -310,12 +307,6 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, page = find_get_page(mapping, index); if (!page) { /* - * Make sure the read-ahead engine is notified - * about this failure. - */ - handle_ra_miss(mapping, &in->f_ra, index); - - /* * page didn't exist, allocate one. */ page = page_cache_alloc_cold(mapping); @@ -360,6 +351,10 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, this_len = min_t(unsigned long, len, PAGE_CACHE_SIZE - loff); page = pages[page_nr]; + if (PageReadahead(page)) + page_cache_async_readahead(mapping, &in->f_ra, in, + page, index, req_pages - page_nr); + /* * If the page isn't uptodate, we may need to start io on it */ @@ -452,6 +447,7 @@ fill_it: */ while (page_nr < nr_pages) page_cache_release(pages[page_nr++]); + in->f_ra.prev_index = index; if (spd.nr_pages) return splice_to_pipe(pipe, &spd); @@ -491,7 +487,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, ret = 0; spliced = 0; - while (len) { + while (len && !spliced) { ret = __generic_file_splice_read(in, ppos, pipe, len, flags); if (ret < 0) @@ -598,7 +594,7 @@ find_page: ret = add_to_page_cache_lru(page, mapping, index, GFP_KERNEL); if (unlikely(ret)) - goto out; + goto out_release; } ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len); @@ -654,8 +650,9 @@ find_page: */ mark_page_accessed(page); out: - page_cache_release(page); unlock_page(page); +out_release: + page_cache_release(page); out_ret: return ret; } @@ -961,6 +958,10 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, if (unlikely(ret < 0)) return ret; + ret = security_file_permission(out, MAY_WRITE); + if (unlikely(ret < 0)) + return ret; + return out->f_op->splice_write(pipe, out, ppos, len, flags); } @@ -983,6 +984,10 @@ static long do_splice_to(struct file *in, loff_t *ppos, if (unlikely(ret < 0)) return ret; + ret = security_file_permission(in, MAY_READ); + if (unlikely(ret < 0)) + return ret; + return in->f_op->splice_read(in, ppos, pipe, len, flags); } @@ -1051,15 +1056,11 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, sd->flags &= ~SPLICE_F_NONBLOCK; while (len) { - size_t read_len, max_read_len; + size_t read_len; + loff_t pos = sd->pos; - /* - * Do at most PIPE_BUFFERS pages worth of transfer: - */ - max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE)); - - ret = do_splice_to(in, &sd->pos, pipe, max_read_len, flags); - if (unlikely(ret < 0)) + ret = do_splice_to(in, &pos, pipe, len, flags); + if (unlikely(ret <= 0)) goto out_release; read_len = ret; @@ -1071,26 +1072,18 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, * could get stuck data in the internal pipe: */ ret = actor(pipe, sd); - if (unlikely(ret < 0)) + if (unlikely(ret <= 0)) goto out_release; bytes += ret; len -= ret; + sd->pos = pos; - /* - * In nonblocking mode, if we got back a short read then - * that was due to either an IO error or due to the - * pagecache entry not being there. In the IO error case - * the _next_ splice attempt will produce a clean IO error - * return value (not a short read), so in both cases it's - * correct to break out of the loop here: - */ - if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len)) - break; + if (ret < read_len) + goto out_release; } pipe->nrbufs = pipe->curbuf = 0; - return bytes; out_release: @@ -1152,10 +1145,12 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, .pos = *ppos, .u.file = out, }; - size_t ret; + long ret; ret = splice_direct_to_actor(in, &sd, direct_splice_actor); - *ppos = sd.pos; + if (ret > 0) + *ppos += ret; + return ret; } |