/*
* Default synchronous end-of-IO handler.. Just mark it up-to-date and
- * unlock the buffer. This is what ll_rw_block uses too.
+ * unlock the buffer.
*/
void end_buffer_read_sync(struct buffer_head *bh, int uptodate)
{
* all already-submitted IO to complete, but does not queue any new
* writes to the disk.
*
- * To do O_SYNC writes, just queue the buffer writes with ll_rw_block as
- * you dirty the buffers, and then use osync_inode_buffers to wait for
+ * To do O_SYNC writes, just queue the buffer writes with write_dirty_buffer
+ * as you dirty the buffers, and then use osync_inode_buffers to wait for
* completion. Any other dirty buffers which are not yet queued for
* write will not be flushed to disk by the osync.
*/
struct buffer_head *bh = __find_get_block(bdev, bblock + 1, blocksize);
if (bh) {
if (buffer_dirty(bh))
- ll_rw_block(REQ_OP_WRITE, 1, &bh);
+ write_dirty_buffer(bh, 0);
put_bh(bh);
}
}
{
struct buffer_head *bh = __getblk(bdev, block, size);
if (likely(bh)) {
- ll_rw_block(REQ_OP_READ | REQ_RAHEAD, 1, &bh);
+ bh_readahead(bh, REQ_RAHEAD);
brelse(bh);
}
}
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
static void discard_buffer(struct buffer_head * bh)
{
- unsigned long b_state, b_state_old;
+ unsigned long b_state;
lock_buffer(bh);
clear_buffer_dirty(bh);
bh->b_bdev = NULL;
- b_state = bh->b_state;
- for (;;) {
- b_state_old = cmpxchg(&bh->b_state, b_state,
- (b_state & ~BUFFER_FLAGS_DISCARD));
- if (b_state_old == b_state)
- break;
- b_state = b_state_old;
- }
+ b_state = READ_ONCE(bh->b_state);
+ do {
+ } while (!try_cmpxchg(&bh->b_state, &b_state,
+ b_state & ~BUFFER_FLAGS_DISCARD));
unlock_buffer(bh);
}
/*
* The page was marked dirty, but the buffers were
* clean. Someone wrote them back by hand with
- * ll_rw_block/submit_bh. A rare case.
+ * write_dirty_buffer/submit_bh. A rare case.
*/
end_page_writeback(page);
if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
!buffer_unwritten(bh) &&
(block_start < from || block_end > to)) {
- ll_rw_block(REQ_OP_READ, 1, &bh);
+ bh_read_nowait(bh, 0);
*wait_bh++=bh;
}
}
struct address_space *mapping = inode->i_mapping;
const struct address_space_operations *aops = mapping->a_ops;
struct page *page;
- void *fsdata;
+ void *fsdata = NULL;
int err;
err = inode_newsize_ok(inode, size);
const struct address_space_operations *aops = mapping->a_ops;
unsigned int blocksize = i_blocksize(inode);
struct page *page;
- void *fsdata;
+ void *fsdata = NULL;
pgoff_t index, curidx;
loff_t curpos;
unsigned zerofrom, offset, len;
set_buffer_uptodate(bh);
if (!buffer_uptodate(bh) && !buffer_delay(bh) && !buffer_unwritten(bh)) {
- err = -EIO;
- ll_rw_block(REQ_OP_READ, 1, &bh);
- wait_on_buffer(bh);
+ err = bh_read(bh, 0);
/* Uhhuh. Read error. Complain and punt. */
- if (!buffer_uptodate(bh))
+ if (err < 0)
goto unlock;
}
}
EXPORT_SYMBOL(submit_bh);
-/**
- * ll_rw_block: low-level access to block devices (DEPRECATED)
- * @opf: block layer request operation and flags.
- * @nr: number of &struct buffer_heads in the array
- * @bhs: array of pointers to &struct buffer_head
- *
- * ll_rw_block() takes an array of pointers to &struct buffer_heads, and
- * requests an I/O operation on them, either a %REQ_OP_READ or a %REQ_OP_WRITE.
- * @opf contains flags modifying the detailed I/O behavior, most notably
- * %REQ_RAHEAD.
- *
- * This function drops any buffer that it cannot get a lock on (with the
- * BH_Lock state bit), any buffer that appears to be clean when doing a write
- * request, and any buffer that appears to be up-to-date when doing read
- * request. Further it marks as clean buffers that are processed for
- * writing (the buffer cache won't assume that they are actually clean
- * until the buffer gets unlocked).
- *
- * ll_rw_block sets b_end_io to simple completion handler that marks
- * the buffer up-to-date (if appropriate), unlocks the buffer and wakes
- * any waiters.
- *
- * All of the buffers must be for the same device, and must also be a
- * multiple of the current approved size for the device.
- */
-void ll_rw_block(const blk_opf_t opf, int nr, struct buffer_head *bhs[])
-{
- const enum req_op op = opf & REQ_OP_MASK;
- int i;
-
- for (i = 0; i < nr; i++) {
- struct buffer_head *bh = bhs[i];
-
- if (!trylock_buffer(bh))
- continue;
- if (op == REQ_OP_WRITE) {
- if (test_clear_buffer_dirty(bh)) {
- bh->b_end_io = end_buffer_write_sync;
- get_bh(bh);
- submit_bh(opf, bh);
- continue;
- }
- } else {
- if (!buffer_uptodate(bh)) {
- bh->b_end_io = end_buffer_read_sync;
- get_bh(bh);
- submit_bh(opf, bh);
- continue;
- }
- }
- unlock_buffer(bh);
- }
-}
-EXPORT_SYMBOL(ll_rw_block);
-
void write_dirty_buffer(struct buffer_head *bh, blk_opf_t op_flags)
{
lock_buffer(bh);
EXPORT_SYMBOL(bh_uptodate_or_lock);
/**
- * bh_submit_read - Submit a locked buffer for reading
+ * __bh_read - Submit read for a locked buffer
* @bh: struct buffer_head
+ * @op_flags: appending REQ_OP_* flags besides REQ_OP_READ
+ * @wait: wait until reading finish
*
- * Returns zero on success and -EIO on error.
+ * Returns zero on success or don't wait, and -EIO on error.
*/
-int bh_submit_read(struct buffer_head *bh)
+int __bh_read(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
{
- BUG_ON(!buffer_locked(bh));
+ int ret = 0;
- if (buffer_uptodate(bh)) {
- unlock_buffer(bh);
- return 0;
- }
+ BUG_ON(!buffer_locked(bh));
get_bh(bh);
bh->b_end_io = end_buffer_read_sync;
- submit_bh(REQ_OP_READ, bh);
- wait_on_buffer(bh);
- if (buffer_uptodate(bh))
- return 0;
- return -EIO;
+ submit_bh(REQ_OP_READ | op_flags, bh);
+ if (wait) {
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh))
+ ret = -EIO;
+ }
+ return ret;
+}
+EXPORT_SYMBOL(__bh_read);
+
+/**
+ * __bh_read_batch - Submit read for a batch of unlocked buffers
+ * @nr: entry number of the buffer batch
+ * @bhs: a batch of struct buffer_head
+ * @op_flags: appending REQ_OP_* flags besides REQ_OP_READ
+ * @force_lock: force to get a lock on the buffer if set, otherwise drops any
+ * buffer that cannot lock.
+ *
+ * Returns zero on success or don't wait, and -EIO on error.
+ */
+void __bh_read_batch(int nr, struct buffer_head *bhs[],
+ blk_opf_t op_flags, bool force_lock)
+{
+ int i;
+
+ for (i = 0; i < nr; i++) {
+ struct buffer_head *bh = bhs[i];
+
+ if (buffer_uptodate(bh))
+ continue;
+
+ if (force_lock)
+ lock_buffer(bh);
+ else
+ if (!trylock_buffer(bh))
+ continue;
+
+ if (buffer_uptodate(bh)) {
+ unlock_buffer(bh);
+ continue;
+ }
+
+ bh->b_end_io = end_buffer_read_sync;
+ get_bh(bh);
+ submit_bh(REQ_OP_READ | op_flags, bh);
+ }
}
-EXPORT_SYMBOL(bh_submit_read);
+EXPORT_SYMBOL(__bh_read_batch);
void __init buffer_init(void)
{
projects / platform / kernel / linux-starfive.git / blobdiff