diff options
| -rw-r--r-- | drivers/mtd/parsers/afs.c | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/drivers/mtd/parsers/afs.c b/drivers/mtd/parsers/afs.c index c489938cd665..ccc198818057 100644 --- a/drivers/mtd/parsers/afs.c +++ b/drivers/mtd/parsers/afs.c @@ -68,6 +68,26 @@ static u32 word_sum(void *words, int num) return sum; } +static bool afs_is_v1(struct mtd_info *mtd, u_int off) +{ + /* The magic is 12 bytes from the end of the erase block */ + u_int ptr = off + mtd->erasesize - 12; + u32 magic; + size_t sz; + int ret; + + ret = mtd_read(mtd, ptr, 4, &sz, (u_char *)&magic); + if (ret < 0) { + printk(KERN_ERR "AFS: mtd read failed at 0x%x: %d\n", + ptr, ret); + return false; + } + if (ret >= 0 && sz != 4) + return false; + + return (magic == AFSV1_FOOTER_MAGIC); +} + static int afs_read_footer_v1(struct mtd_info *mtd, u_int *img_start, u_int *iis_start, u_int off, u_int mask) @@ -176,18 +196,9 @@ static int parse_afs_partitions(struct mtd_info *mtd, */ mask = mtd->size - 1; - /* - * First, calculate the size of the array we need for the - * partition information. We include in this the size of - * the strings. - */ + /* Count the partitions by looping over all erase blocks */ for (i = off = sz = 0; off < mtd->size; off += mtd->erasesize) { - u_int iis_ptr, img_ptr; - - ret = afs_read_footer_v1(mtd, &img_ptr, &iis_ptr, off, mask); - if (ret < 0) - return ret; - if (ret) { + if (afs_is_v1(mtd, off)) { sz += sizeof(struct mtd_partition); i += 1; } |