bio_map_user_iov(): move alignment check into the main loop
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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parent
e2e115d18b
commit
98f0bc9905
1 changed files with 23 additions and 23 deletions
46
block/bio.c
46
block/bio.c
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@ -1344,11 +1344,6 @@ struct bio *bio_map_user_iov(struct request_queue *q,
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return ERR_PTR(-EINVAL);
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nr_pages += end - start;
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/*
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* buffer must be aligned to at least logical block size for now
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*/
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if (uaddr & queue_dma_alignment(q))
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return ERR_PTR(-EINVAL);
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}
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if (!nr_pages)
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@ -1373,29 +1368,34 @@ struct bio *bio_map_user_iov(struct request_queue *q,
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npages = DIV_ROUND_UP(offs + bytes, PAGE_SIZE);
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for (j = 0; j < npages; j++) {
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unsigned int n = PAGE_SIZE - offs;
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unsigned short prev_bi_vcnt = bio->bi_vcnt;
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if (unlikely(offs & queue_dma_alignment(q))) {
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ret = -EINVAL;
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j = 0;
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} else {
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for (j = 0; j < npages; j++) {
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struct page *page = pages[j];
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unsigned int n = PAGE_SIZE - offs;
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unsigned short prev_bi_vcnt = bio->bi_vcnt;
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if (n > bytes)
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n = bytes;
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if (n > bytes)
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n = bytes;
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if (!bio_add_pc_page(q, bio, pages[j], n, offs))
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break;
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if (!bio_add_pc_page(q, bio, page, n, offs))
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break;
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/*
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* check if vector was merged with previous
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* drop page reference if needed
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*/
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if (bio->bi_vcnt == prev_bi_vcnt)
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put_page(pages[j]);
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/*
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* check if vector was merged with previous
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* drop page reference if needed
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*/
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if (bio->bi_vcnt == prev_bi_vcnt)
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put_page(page);
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added += n;
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bytes -= n;
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offs = 0;
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added += n;
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bytes -= n;
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offs = 0;
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}
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iov_iter_advance(&i, added);
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}
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iov_iter_advance(&i, added);
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/*
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* release the pages we didn't map into the bio, if any
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*/
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