From: Andrey Smirnov <andrew.smirnov@gmail.com>
To: barebox@lists.infradead.org
Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
Subject: [PATCH 1/2] block: Do not write past block device boundary during a flush
Date: Mon, 21 Jan 2019 22:06:24 -0800 [thread overview]
Message-ID: <20190122060625.12337-1-andrew.smirnov@gmail.com> (raw)
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>
---
common/block.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/common/block.c b/common/block.c
index 35173c65f..3a031a4fc 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;
--
2.20.1
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
next reply other threads:[~2019-01-22 6:06 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-22 6:06 Andrey Smirnov [this message]
2019-01-22 6:06 ` [PATCH 2/2] block: Move shared code in get_chunk() out of if statement Andrey Smirnov
2019-01-22 7:57 ` [PATCH 1/2] block: Do not write past block device boundary during a flush Sascha Hauer
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190122060625.12337-1-andrew.smirnov@gmail.com \
--to=andrew.smirnov@gmail.com \
--cc=barebox@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox