mtd: afs: simplify partition detection

Instead of reading out the AFS footers twice, create a separate
function to just check if there is a footer or not. Rids a few
local variables and prepare us to join the actual parser into
one function.

Cc: Ryan Harkin <ryan.harkin@linaro.org>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Linus Walleij 2019-05-02 16:30:30 +02:00 committed by Richard Weinberger
parent 1fca1f6abb
commit 2070017192
1 changed files with 22 additions and 11 deletions

View File

@ -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;
}