All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dmitriy Monakhov <dmonakhov@sw.ru>
To: linux-kernel@vger.kernel.org
Cc: npiggin@suse.de, mark.fasheh@oracle.com, linux-ext4@vger.kernel.org
Subject: [patch] new aop loop fix
Date: Wed, 13 Jun 2007 17:46:31 +0400	[thread overview]
Message-ID: <20070613134631.GB13815@localhost.sw.ru> (raw)

	loop.c code itself is not perfect. In fact before Nick's patch
	partial write was't possible. Assumption what write chunks are
	always page aligned is realy weird ( see "index++" line).

Signed-off-by: Dmitriy Monakhov <dmonakhov@openvz.org>

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 4bab9b1..8726da5 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -215,7 +215,6 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
 	int len, ret;
 
 	mutex_lock(&mapping->host->i_mutex);
-	index = pos >> PAGE_CACHE_SHIFT;
 	offset = pos & ((pgoff_t)PAGE_CACHE_SIZE - 1);
 	bv_offs = bvec->bv_offset;
 	len = bvec->bv_len;
@@ -226,6 +225,7 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
 		struct page *page;
 		void *fsdata;
 
+		index = pos >> PAGE_CACHE_SHIFT;
 		IV = ((sector_t)index << (PAGE_CACHE_SHIFT - 9))+(offset >> 9);
 		size = PAGE_CACHE_SIZE - offset;
 		if (size > len)
@@ -255,7 +255,6 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
 		bv_offs += copied;
 		len -= copied;
 		offset = 0;
-		index++;
 		pos += copied;
 	}
 	ret = 0;

> 
> 

             reply	other threads:[~2007-06-13 10:45 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-13 13:46 Dmitriy Monakhov [this message]
2007-06-13 13:36 ` [patch] new aop loop fix Hugh Dickins
2007-06-13 17:29   ` Dmitriy Monakhov
2007-06-13 14:48     ` Hugh Dickins
2007-06-16 15:39       ` [PATCH] deny partial write for loop dev fd Dmitriy Monakhov
2007-06-18  2:39         ` Nick Piggin

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=20070613134631.GB13815@localhost.sw.ru \
    --to=dmonakhov@sw.ru \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.fasheh@oracle.com \
    --cc=npiggin@suse.de \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.