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authorAndrey Smirnov <andrew.smirnov@gmail.com>2019-01-21 22:06:24 -0800
committerSascha Hauer <s.hauer@pengutronix.de>2019-01-22 08:57:21 +0100
commit17c4b989a5d00fe5fc84c528bbd59583c45d80d0 (patch)
treedbe49644ba01922270c74b85df7f9499cdfe9b40 /common
parentcee4c2a064796db730c572bf8973e799c1b89b02 (diff)
downloadbarebox-17c4b989a5d00fe5fc84c528bbd59583c45d80d0.tar.gz
block: Do not write past block device boundary during a flush
When calling I/O functions of underlying block device driver we always need to make sure that its size is small enough to not go past device's boundary. Not only in get_chunk() and block_cache(), but in writebuffer_flush() as well. Since the same code is used in three different places, move it into a subroutine and adjust all of the calls to ->write()/->read() accordingly. Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'common')
-rw-r--r--common/block.c22
1 files changed, 13 insertions, 9 deletions
diff --git a/common/block.c b/common/block.c
index 35173c6..3a031a4 100644
--- a/common/block.c
+++ b/common/block.c
@@ -38,6 +38,11 @@ struct chunk {
#define BUFSIZE (PAGE_SIZE * 4)
+static int writebuffer_io_len(struct block_device *blk, struct chunk *chunk)
+{
+ return min(blk->rdbufsize, blk->num_blocks - chunk->block_start);
+}
+
/*
* Write all dirty chunks back to the device
*/
@@ -51,7 +56,9 @@ static int writebuffer_flush(struct block_device *blk)
list_for_each_entry(chunk, &blk->buffered_blocks, list) {
if (chunk->dirty) {
- ret = blk->ops->write(blk, chunk->data, chunk->block_start, blk->rdbufsize);
+ ret = blk->ops->write(blk, chunk->data,
+ chunk->block_start,
+ writebuffer_io_len(blk, chunk));
if (ret < 0)
return ret;
@@ -118,10 +125,9 @@ static struct chunk *get_chunk(struct block_device *blk)
/* use last entry which is the most unused */
chunk = list_last_entry(&blk->buffered_blocks, struct chunk, list);
if (chunk->dirty) {
- size_t num_blocks = min(blk->rdbufsize,
- blk->num_blocks - chunk->block_start);
- ret = blk->ops->write(blk, chunk->data, chunk->block_start,
- num_blocks);
+ ret = blk->ops->write(blk, chunk->data,
+ chunk->block_start,
+ writebuffer_io_len(blk, chunk));
if (ret < 0)
return ERR_PTR(ret);
@@ -145,7 +151,6 @@ static struct chunk *get_chunk(struct block_device *blk)
static int block_cache(struct block_device *blk, int block)
{
struct chunk *chunk;
- size_t num_blocks;
int ret;
chunk = get_chunk(blk);
@@ -157,9 +162,8 @@ static int block_cache(struct block_device *blk, int block)
dev_dbg(blk->dev, "%s: %d to %d\n", __func__, chunk->block_start,
chunk->num);
- num_blocks = min(blk->rdbufsize, blk->num_blocks - chunk->block_start);
-
- ret = blk->ops->read(blk, chunk->data, chunk->block_start, num_blocks);
+ ret = blk->ops->read(blk, chunk->data, chunk->block_start,
+ writebuffer_io_len(blk, chunk));
if (ret) {
list_add_tail(&chunk->list, &blk->idle_blocks);
return ret;