[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>
diff --git a/fs/jffs2/gc.c b/fs/jffs2/gc.c
index 694bc90..7086cd6 100644
--- a/fs/jffs2/gc.c
+++ b/fs/jffs2/gc.c
@@ -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 @@
{
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 @@
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 @@
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 @@
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 @@
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 @@
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);
}
diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
index 57f675c..a65539f 100644
--- a/fs/jffs2/nodelist.h
+++ b/fs/jffs2/nodelist.h
@@ -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 @@
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)
