From: Linus Walleij <linus.walleij@linaro.org>
To: David Woodhouse <dwmw2@infradead.org>,
Brian Norris <computersforpeace@gmail.com>,
Boris Brezillon <boris.brezillon@free-electrons.com>,
Marek Vasut <marek.vasut@gmail.com>,
Richard Weinberger <richard@nod.at>,
Cyrille Pitchen <cyrille.pitchen@atmel.com>,
linux-mtd@lists.infradead.org
Cc: Linus Walleij <linus.walleij@linaro.org>,
Liviu Dudau <liviu.dudau@arm.com>,
Ryan Harkin <ryan.harkin@linaro.org>
Subject: [PATCH 2/6] mtd: afs: simplify partition detection
Date: Mon, 28 Jan 2019 14:54:45 +0100 [thread overview]
Message-ID: <20190128135449.15555-3-linus.walleij@linaro.org> (raw)
In-Reply-To: <20190128135449.15555-1-linus.walleij@linaro.org>
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>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/mtd/parsers/afs.c | 33 ++++++++++++++++++++++-----------
1 file 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;
}
--
2.20.1
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next prev parent reply other threads:[~2019-01-28 13:55 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-28 13:54 [PATCH 0/6] mtd: afs: Support AFSv2 parsing Linus Walleij
2019-01-28 13:54 ` [PATCH 1/6] mtd: afs: simplify partition parsing Linus Walleij
2019-01-31 17:13 ` Liviu Dudau
2019-01-31 17:45 ` Boris Brezillon
2019-02-05 11:25 ` Liviu Dudau
2019-02-12 14:31 ` Liviu Dudau
2019-01-28 13:54 ` Linus Walleij [this message]
2019-01-28 13:54 ` [PATCH 3/6] mtd: factor out v1 " Linus Walleij
2019-01-28 13:54 ` [PATCH 4/6] mtd: afs: factor footer parsing into the v1 part parsing Linus Walleij
2019-01-28 13:54 ` [PATCH 5/6] mtd: afs: factor the IIS read into partition parser Linus Walleij
2019-01-28 13:54 ` [PATCH 6/6] mtd: afs: add v2 partition parsing Linus Walleij
2019-04-28 11:38 ` [PATCH 0/6] mtd: afs: Support AFSv2 parsing Linus Walleij
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