}
EXPORT_SYMBOL(__breadahead);
+void __breadahead_gfp(struct block_device *bdev, sector_t block, unsigned size,
+ gfp_t gfp)
+{
+ struct buffer_head *bh = __getblk_gfp(bdev, block, size, gfp);
+ if (likely(bh)) {
+ ll_rw_block(REQ_OP_READ, REQ_RAHEAD, 1, &bh);
+ brelse(bh);
+ }
+}
+EXPORT_SYMBOL(__breadahead_gfp);
+
/**
* __bread_gfp() - reads a specified block and returns the bh
* @bdev: the block_device to read from
/* Is the page fully outside i_size? (truncate in progress) */
offset = i_size & (PAGE_SIZE-1);
if (page->index >= end_index+1 || !offset) {
- /*
- * The page may have dirty, unmapped buffers. For example,
- * they may have been added in ext3_writepage(). Make them
- * freeable here, so the page does not leak.
- */
-#if 0
- /* Not really sure about this - do we need this ? */
- if (page->mapping->a_ops->invalidatepage)
- page->mapping->a_ops->invalidatepage(page, offset);
-#endif
unlock_page(page);
return 0; /* don't care */
}
/* Is the page fully outside i_size? (truncate in progress) */
offset = i_size & (PAGE_SIZE-1);
if (page->index >= end_index+1 || !offset) {
- /*
- * The page may have dirty, unmapped buffers. For example,
- * they may have been added in ext3_writepage(). Make them
- * freeable here, so the page does not leak.
- */
- do_invalidatepage(page, 0, PAGE_SIZE);
unlock_page(page);
return 0; /* don't care */
}
* errors, this only handles the "we need to be able to
* do IO at the final sector" case.
*/
-void guard_bio_eod(int op, struct bio *bio)
+void guard_bio_eod(struct bio *bio)
{
sector_t maxsector;
- struct bio_vec *bvec = bio_last_bvec_all(bio);
- unsigned truncated_bytes;
struct hd_struct *part;
rcu_read_lock();
if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))
return;
- /* Uhhuh. We've got a bio that straddles the device size! */
- truncated_bytes = bio->bi_iter.bi_size - (maxsector << 9);
-
- /*
- * The bio contains more than one segment which spans EOD, just return
- * and let IO layer turn it into an EIO
- */
- if (truncated_bytes > bvec->bv_len)
- return;
-
- /* Truncate the bio.. */
- bio->bi_iter.bi_size -= truncated_bytes;
- bvec->bv_len -= truncated_bytes;
-
- /* ..and clear the end of the buffer for reads */
- if (op == REQ_OP_READ) {
- struct bio_vec bv;
-
- mp_bvec_last_segment(bvec, &bv);
- zero_user(bv.bv_page, bv.bv_offset + bv.bv_len,
- truncated_bytes);
- }
+ bio_truncate(bio, maxsector << 9);
}
static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
bio->bi_end_io = end_bio_bh_io_sync;
bio->bi_private = bh;
- /* Take care of bh's that straddle the end of the device */
- guard_bio_eod(op, bio);
-
if (buffer_meta(bh))
op_flags |= REQ_META;
if (buffer_prio(bh))
op_flags |= REQ_PRIO;
bio_set_op_attrs(bio, op, op_flags);
+ /* Take care of bh's that straddle the end of the device */
+ guard_bio_eod(bio);
+
if (wbc) {
wbc_init_bio(wbc, bio);
wbc_account_cgroup_owner(wbc, bh->b_page, bh->b_size);
WARN_ON(atomic_read(&bh->b_count) < 1);
lock_buffer(bh);
if (test_clear_buffer_dirty(bh)) {
+ /*
+ * The bh should be mapped, but it might not be if the
+ * device was hot-removed. Not much we can do but fail the I/O.
+ */
+ if (!buffer_mapped(bh)) {
+ unlock_buffer(bh);
+ return -EIO;
+ }
+
get_bh(bh);
bh->b_end_io = end_buffer_write_sync;
ret = submit_bh(REQ_OP_WRITE, op_flags, bh);