diff options
| -rw-r--r-- | mm/filemap.c | 117 |
1 files changed, 51 insertions, 66 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 65d9d9e2b75..6343f3c841b 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -42,9 +42,6 @@ #include <asm/mman.h> -static ssize_t -generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, - loff_t offset, unsigned long nr_segs); /* * Shared mappings implemented 30.11.1994. It's not fully working yet, @@ -1205,8 +1202,11 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov, goto out; /* skip atime */ size = i_size_read(inode); if (pos < size) { - retval = generic_file_direct_IO(READ, iocb, - iov, pos, nr_segs); + retval = filemap_write_and_wait(mapping); + if (!retval) { + retval = mapping->a_ops->direct_IO(READ, iocb, + iov, pos, nr_segs); + } if (retval > 0) *ppos = pos + retval; } @@ -2004,11 +2004,55 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov, struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; ssize_t written; + size_t write_len; + pgoff_t end; if (count != ocount) *nr_segs = iov_shorten((struct iovec *)iov, *nr_segs, count); - written = generic_file_direct_IO(WRITE, iocb, iov, pos, *nr_segs); + /* + * Unmap all mmappings of the file up-front. + * + * This will cause any pte dirty bits to be propagated into the + * pageframes for the subsequent filemap_write_and_wait(). + */ + write_len = iov_length(iov, *nr_segs); + end = (pos + write_len - 1) >> PAGE_CACHE_SHIFT; + if (mapping_mapped(mapping)) + unmap_mapping_range(mapping, pos, write_len, 0); + + written = filemap_write_and_wait(mapping); + if (written) + goto out; + + /* + * After a write we want buffered reads to be sure to go to disk to get + * the new data. We invalidate clean cached page from the region we're + * about to write. We do this *before* the write so that we can return + * -EIO without clobbering -EIOCBQUEUED from ->direct_IO(). + */ + if (mapping->nrpages) { + written = invalidate_inode_pages2_range(mapping, + pos >> PAGE_CACHE_SHIFT, end); + if (written) + goto out; + } + + written = mapping->a_ops->direct_IO(WRITE, iocb, iov, pos, *nr_segs); + + /* + * Finally, try again to invalidate clean pages which might have been + * cached by non-direct readahead, or faulted in by get_user_pages() + * if the source of the write was an mmap'ed region of the file + * we're writing. Either one is a pretty crazy thing to do, + * so we don't support it 100%. If this invalidation + * fails, tough, the write still worked... + */ + if (mapping->nrpages) { + invalidate_inode_pages2_range(mapping, + pos >> PAGE_CACHE_SHIFT, end); + } + if (written > 0) { loff_t end = pos + written; if (end > i_size_read(inode) && !S_ISBLK(inode->i_mode)) { @@ -2024,6 +2068,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov, * i_mutex is held, which protects generic_osync_inode() from * livelocking. AIO O_DIRECT ops attempt to sync metadata here. */ +out: if ((written >= 0 || written == -EIOCBQUEUED) && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { int err = generic_osync_inode(inode, mapping, OSYNC_METADATA); @@ -2511,66 +2556,6 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov, } EXPORT_SYMBOL(generic_file_aio_write); -/* - * Called under i_mutex for writes to S_ISREG files. Returns -EIO if something - * went wrong during pagecache shootdown. - */ -static ssize_t -generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, - loff_t offset, unsigned long nr_segs) -{ - struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - ssize_t retval; - size_t write_len; - pgoff_t end = 0; /* silence gcc */ - - /* - * If it's a write, unmap all mmappings of the file up-front. This - * will cause any pte dirty bits to be propagated into the pageframes - * for the subsequent filemap_write_and_wait(). - */ - if (rw == WRITE) { - write_len = iov_length(iov, nr_segs); - end = (offset + write_len - 1) >> PAGE_CACHE_SHIFT; - if (mapping_mapped(mapping)) - unmap_mapping_range(mapping, offset, write_len, 0); - } - - retval = filemap_write_and_wait(mapping); - if (retval) - goto out; - - /* - * After a write we want buffered reads to be sure to go to disk to get - * the new data. We invalidate clean cached page from the region we're - * about to write. We do this *before* the write so that we can return - * -EIO without clobbering -EIOCBQUEUED from ->direct_IO(). - */ - if (rw == WRITE && mapping->nrpages) { - retval = invalidate_inode_pages2_range(mapping, - offset >> PAGE_CACHE_SHIFT, end); - if (retval) - goto out; - } - - retval = mapping->a_ops->direct_IO(rw, iocb, iov, offset, nr_segs); - - /* - * Finally, try again to invalidate clean pages which might have been - * cached by non-direct readahead, or faulted in by get_user_pages() - * if the source of the write was an mmap'ed region of the file - * we're writing. Either one is a pretty crazy thing to do, - * so we don't support it 100%. If this invalidation - * fails, tough, the write still worked... - */ - if (rw == WRITE && mapping->nrpages) { - invalidate_inode_pages2_range(mapping, offset >> PAGE_CACHE_SHIFT, end); - } -out: - return retval; -} - /** * try_to_release_page() - release old fs-specific metadata on a page * |