JFFS2: Only list each directory entry once
authorMark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Wed, 1 Jul 2015 04:38:24 +0000 (16:38 +1200)
committerLothar Waßmann <LW@KARO-electronics.de>
Thu, 10 Sep 2015 06:24:12 +0000 (08:24 +0200)
If multiple versions of a file exist, only the most recent version
should be used. The scheme to write 0 for the inode in older versions
did not work, since this would have required writing to flash.

The only time this caused an issue was listing a directory, where older
versions of the file would still be seen. Since the directory entries
are sorted, just look at the next entry in the list, and if it's the same
move to that entry instead.

Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
fs/jffs2/jffs2_1pass.c

index aaeb522..346f3a1 100644 (file)
@@ -845,7 +845,6 @@ jffs2_1pass_find_inode(struct b_lists * pL, const char *name, u32 pino)
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
                if ((pino == jDir->pino) && (len == jDir->nsize) &&
-                   (jDir->ino) &&      /* 0 for unlink */
                    (!strncmp((char *)jDir->name, name, len))) {        /* a match */
                        if (jDir->version < version) {
                                put_fl_mem(jDir, pL->readbuf);
@@ -966,13 +965,43 @@ jffs2_1pass_list_inodes(struct b_lists * pL, u32 pino)
        for (b = pL->dir.listHead; b; b = b->next) {
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
-               if ((pino == jDir->pino) && (jDir->ino)) { /* ino=0 -> unlink */
+               if (pino == jDir->pino) {
                        u32 i_version = 0;
                        struct jffs2_raw_inode ojNode;
                        struct jffs2_raw_inode *jNode, *i = NULL;
-                       struct b_node *b2 = pL->frag.listHead;
+                       struct b_node *b2;
 
-                       while (b2) {
+#ifdef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
+                       /* Check for more recent versions of this file */
+                       int match;
+                       do {
+                               struct b_node *next = b->next;
+                               struct jffs2_raw_dirent *jDirNext;
+                               if (!next)
+                                       break;
+                               jDirNext = (struct jffs2_raw_dirent *)
+                                       get_node_mem(next->offset, NULL);
+                               match = jDirNext->pino == jDir->pino &&
+                                       jDirNext->nsize == jDir->nsize &&
+                                       strncmp((char *)jDirNext->name,
+                                               (char *)jDir->name,
+                                               jDir->nsize) == 0;
+                               if (match) {
+                                       /* Use next. It is more recent */
+                                       b = next;
+                                       /* Update buffer with the new info */
+                                       *jDir = *jDirNext;
+                               }
+                               put_fl_mem(jDirNext, NULL);
+                       } while (match);
+#endif
+                       if (jDir->ino == 0) {
+                               /* Deleted file */
+                               put_fl_mem(jDir, pL->readbuf);
+                               continue;
+                       }
+
+                       for (b2 = pL->frag.listHead; b2; b2 = b2->next) {
                                jNode = (struct jffs2_raw_inode *)
                                        get_fl_mem(b2->offset, sizeof(ojNode), &ojNode);
                                if (jNode->ino == jDir->ino && jNode->version >= i_version) {
@@ -988,7 +1017,6 @@ jffs2_1pass_list_inodes(struct b_lists * pL, u32 pino)
                                                               sizeof(*i),
                                                               NULL);
                                }
-                               b2 = b2->next;
                        }
 
                        dump_inode(pL, jDir, i);