diff options
Diffstat (limited to 'fs/iomap/direct-io.c')
| -rw-r--r-- | fs/iomap/direct-io.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 420c0c82f0ac..23837926c0c5 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -201,12 +201,12 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, unsigned int blkbits = blksize_bits(bdev_logical_block_size(iomap->bdev)); unsigned int fs_block_size = i_blocksize(inode), pad; unsigned int align = iov_iter_alignment(dio->submit.iter); - struct iov_iter iter; struct bio *bio; bool need_zeroout = false; bool use_fua = false; int nr_pages, ret = 0; size_t copied = 0; + size_t orig_count; if ((pos | length | align) & ((1 << blkbits) - 1)) return -EINVAL; @@ -236,15 +236,18 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, } /* - * Operate on a partial iter trimmed to the extent we were called for. - * We'll update the iter in the dio once we're done with this extent. + * Save the original count and trim the iter to just the extent we + * are operating on right now. The iter will be re-expanded once + * we are done. */ - iter = *dio->submit.iter; - iov_iter_truncate(&iter, length); + orig_count = iov_iter_count(dio->submit.iter); + iov_iter_truncate(dio->submit.iter, length); - nr_pages = iov_iter_npages(&iter, BIO_MAX_PAGES); - if (nr_pages <= 0) - return nr_pages; + nr_pages = iov_iter_npages(dio->submit.iter, BIO_MAX_PAGES); + if (nr_pages <= 0) { + ret = nr_pages; + goto out; + } if (need_zeroout) { /* zero out from the start of the block to the write offset */ @@ -257,7 +260,8 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, size_t n; if (dio->error) { iov_iter_revert(dio->submit.iter, copied); - return 0; + copied = ret = 0; + goto out; } bio = bio_alloc(GFP_KERNEL, nr_pages); @@ -268,7 +272,7 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, bio->bi_private = dio; bio->bi_end_io = iomap_dio_bio_end_io; - ret = bio_iov_iter_get_pages(bio, &iter); + ret = bio_iov_iter_get_pages(bio, dio->submit.iter); if (unlikely(ret)) { /* * We have to stop part way through an IO. We must fall @@ -294,13 +298,11 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, bio_set_pages_dirty(bio); } - iov_iter_advance(dio->submit.iter, n); - dio->size += n; pos += n; copied += n; - nr_pages = iov_iter_npages(&iter, BIO_MAX_PAGES); + nr_pages = iov_iter_npages(dio->submit.iter, BIO_MAX_PAGES); iomap_dio_submit_bio(dio, iomap, bio); } while (nr_pages); @@ -318,6 +320,9 @@ zero_tail: if (pad) iomap_dio_zero(dio, iomap, pos, fs_block_size - pad); } +out: + /* Undo iter limitation to current extent */ + iov_iter_reexpand(dio->submit.iter, orig_count - copied); if (copied) return copied; return ret; @@ -400,7 +405,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, struct address_space *mapping = iocb->ki_filp->f_mapping; struct inode *inode = file_inode(iocb->ki_filp); size_t count = iov_iter_count(iter); - loff_t pos = iocb->ki_pos, start = pos; + loff_t pos = iocb->ki_pos; loff_t end = iocb->ki_pos + count - 1, ret = 0; unsigned int flags = IOMAP_DIRECT; struct blk_plug plug; @@ -456,14 +461,14 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, } if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_has_page(mapping, start, end)) { + if (filemap_range_has_page(mapping, pos, end)) { ret = -EAGAIN; goto out_free_dio; } flags |= IOMAP_NOWAIT; } - ret = filemap_write_and_wait_range(mapping, start, end); + ret = filemap_write_and_wait_range(mapping, pos, end); if (ret) goto out_free_dio; @@ -474,7 +479,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, * pretty crazy thing to do, so we don't support it 100%. */ ret = invalidate_inode_pages2_range(mapping, - start >> PAGE_SHIFT, end >> PAGE_SHIFT); + pos >> PAGE_SHIFT, end >> PAGE_SHIFT); if (ret) dio_warn_stale_pagecache(iocb->ki_filp); ret = 0; |