Commit 67d9e95c authored by Estelle Hammache's avatar Estelle Hammache Committed by Thomas Gleixner
Browse files

[JFFS2] Prevent deadlock during write buffer recovery 



Prevent deadlock when checking erased block for
space allocation during wbuf recovery.

Signed-off-by: default avatarEstelle Hammache <estelle.hammache@st.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 72b56a2d

fs/jffs2/wbuf.c

+8 −4
Original line number Diff line number Diff line
@@ -9,7 +9,7 @@ 
 *

 * For licensing information, see the file 'LICENCE' in this directory.

 *

 * $Id: wbuf.c,v 1.85 2005/02/02 22:12:04 dwmw2 Exp $

 * $Id: wbuf.c,v 1.86 2005/02/05 18:23:37 hammache Exp $

 *

 */
@@ -865,7 +865,6 @@ int jffs2_flash_read(struct jffs2_sb_info *c, loff_t ofs, size_t len, size_t *re 


	/* Read flash */

	if (!jffs2_can_mark_obsolete(c)) {

		down_read(&c->wbuf_sem);



		if (jffs2_cleanmarker_oob(c))

			ret = c->mtd->read_ecc(c->mtd, ofs, len, retlen, buf, NULL, c->oobinfo);
@@ -892,11 +891,16 @@ int jffs2_flash_read(struct jffs2_sb_info *c, loff_t ofs, size_t len, size_t *re 


	/* if no writebuffer available or write buffer empty, return */

	if (!c->wbuf_pagesize || !c->wbuf_len)

		goto exit;

		return ret;;



	/* if we read in a different block, return */

	if ( (ofs & ~(c->sector_size-1)) != (c->wbuf_ofs & ~(c->sector_size-1)) ) 

		goto exit;

		return ret;



	/* Lock only if we have reason to believe wbuf contains relevant data,

	   so that checking an erased block during wbuf recovery space allocation

	   does not deadlock. */

	down_read(&c->wbuf_sem);



	if (ofs >= c->wbuf_ofs) {

		owbf = (ofs - c->wbuf_ofs);	/* offset in write buffer */