[JFFS2] Fix race in garbage collector

Fix the race problem described here:
http://lists.infradead.org/pipermail/linux-mtd/2005-April/012361.html

Signed-off-by: Artem B. Bityuckiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Artem B. Bityuckiy 2005-04-09 11:47:03 +01:00 committed by Thomas Gleixner
parent abc37e6771
commit 8557fd51c2
2 changed files with 37 additions and 7 deletions

View File

@ -7,7 +7,7 @@
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: gc.c,v 1.147 2005/03/20 21:43:22 dedekind Exp $
* $Id: gc.c,v 1.148 2005/04/09 10:47:00 dedekind Exp $
*
*/
@ -669,9 +669,10 @@ static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_
{
struct jffs2_full_dnode *new_fn;
struct jffs2_raw_inode ri;
struct jffs2_node_frag *last_frag;
jint16_t dev;
char *mdata = NULL, mdatalen = 0;
uint32_t alloclen, phys_ofs;
uint32_t alloclen, phys_ofs, ilen;
int ret;
if (S_ISBLK(JFFS2_F_I_MODE(f)) ||
@ -707,6 +708,14 @@ static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_
goto out;
}
last_frag = frag_last(&f->fragtree);
if (last_frag)
/* Fetch the inode length from the fragtree rather then
* from i_size since i_size may have not been updated yet */
ilen = last_frag->ofs + last_frag->size;
else
ilen = JFFS2_F_I_SIZE(f);
memset(&ri, 0, sizeof(ri));
ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
@ -718,7 +727,7 @@ static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_
ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
ri.isize = cpu_to_je32(JFFS2_F_I_SIZE(f));
ri.isize = cpu_to_je32(ilen);
ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
@ -898,7 +907,7 @@ static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eras
struct jffs2_raw_inode ri;
struct jffs2_node_frag *frag;
struct jffs2_full_dnode *new_fn;
uint32_t alloclen, phys_ofs;
uint32_t alloclen, phys_ofs, ilen;
int ret;
D1(printk(KERN_DEBUG "Writing replacement hole node for ino #%u from offset 0x%x to 0x%x\n",
@ -958,10 +967,19 @@ static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eras
ri.csize = cpu_to_je32(0);
ri.compr = JFFS2_COMPR_ZERO;
}
frag = frag_last(&f->fragtree);
if (frag)
/* Fetch the inode length from the fragtree rather then
* from i_size since i_size may have not been updated yet */
ilen = frag->ofs + frag->size;
else
ilen = JFFS2_F_I_SIZE(f);
ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
ri.isize = cpu_to_je32(JFFS2_F_I_SIZE(f));
ri.isize = cpu_to_je32(ilen);
ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
@ -1168,7 +1186,7 @@ static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_era
D1(printk(KERN_DEBUG "Expanded dnode to write from (0x%x-0x%x) to (0x%x-0x%x)\n",
orig_start, orig_end, start, end));
BUG_ON(end > JFFS2_F_I_SIZE(f));
D1(BUG_ON(end > frag_last(&f->fragtree)->ofs + frag_last(&f->fragtree)->size));
BUG_ON(end < orig_end);
BUG_ON(start > orig_start);
}

View File

@ -7,7 +7,7 @@
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: nodelist.h,v 1.128 2005/02/27 23:01:32 dwmw2 Exp $
* $Id: nodelist.h,v 1.130 2005/04/09 10:46:59 dedekind Exp $
*
*/
@ -363,6 +363,18 @@ static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
node = node->rb_left;
return rb_entry(node, struct jffs2_node_frag, rb);
}
static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
{
struct rb_node *node = root->rb_node;
if (!node)
return NULL;
while(node->rb_right)
node = node->rb_right;
return rb_entry(node, struct jffs2_node_frag, rb);
}
#define rb_parent(rb) ((rb)->rb_parent)
#define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
#define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)