From c5b1940f5729232b9230d4e669d30d29fa72c9b7 Mon Sep 17 00:00:00 2001 From: Mark Tomlinson Date: Wed, 1 Jul 2015 16:38:26 +1200 Subject: [PATCH] JFFS2: Optimize building lists during scan If the flash is slow, reading less from the flash into buffers makes the process faster. Signed-off-by: Mark Tomlinson --- fs/jffs2/jffs2_1pass.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/fs/jffs2/jffs2_1pass.c b/fs/jffs2/jffs2_1pass.c index e58e7d25cf..f488537c9f 100644 --- a/fs/jffs2/jffs2_1pass.c +++ b/fs/jffs2/jffs2_1pass.c @@ -1501,7 +1501,7 @@ jffs2_1pass_build_lists(struct part_info * part) u32 counterF = 0; u32 counterN = 0; u32 max_totlen = 0; - u32 buf_size = DEFAULT_EMPTY_SCAN_SIZE; + u32 buf_size; char *buf; nr_sectors = lldiv(part->size, part->sector_size); @@ -1513,7 +1513,7 @@ jffs2_1pass_build_lists(struct part_info * part) /* if we are building a list we need to refresh the cache. */ jffs_init_1pass_list(part); pL = (struct b_lists *)part->jffs2_priv; - buf = malloc(buf_size); + buf = malloc(DEFAULT_EMPTY_SCAN_SIZE); puts ("Scanning JFFS2 FS: "); /* start at the beginning of the partition */ @@ -1529,6 +1529,8 @@ jffs2_1pass_build_lists(struct part_info * part) int ret; #endif + /* Set buf_size to maximum length */ + buf_size = DEFAULT_EMPTY_SCAN_SIZE; WATCHDOG_RESET(); #ifdef CONFIG_JFFS2_SUMMARY @@ -1603,6 +1605,11 @@ jffs2_1pass_build_lists(struct part_info * part) ofs += sector_ofs; prevofs = ofs - 1; + /* + * Set buf_size down to the minimum size required. + * This prevents reading in chunks of flash data unnecessarily. + */ + buf_size = sizeof(union jffs2_node_union); scan_more: while (ofs < sector_ofs + part->sector_size) { @@ -1683,13 +1690,18 @@ jffs2_1pass_build_lists(struct part_info * part) case JFFS2_NODETYPE_INODE: if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { + buf_len = min_t(uint32_t, + sizeof(struct jffs2_raw_inode), + sector_ofs + + part->sector_size - + ofs); get_fl_mem((u32)part->offset + ofs, buf_len, buf); buf_ofs = ofs; node = (void *)buf; } - if (!inode_crc((struct jffs2_raw_inode *) node)) - break; + if (!inode_crc((struct jffs2_raw_inode *)node)) + break; if (insert_node(&pL->frag, (u32) part->offset + ofs) == NULL) { @@ -1706,6 +1718,11 @@ jffs2_1pass_build_lists(struct part_info * part) ((struct jffs2_raw_dirent *) node)->nsize) { + buf_len = min_t(uint32_t, + node->totlen, + sector_ofs + + part->sector_size - + ofs); get_fl_mem((u32)part->offset + ofs, buf_len, buf); buf_ofs = ofs; -- 2.30.2