From patchwork Sun Aug 26 17:21:39 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [2/3] mtd: cmdlinepart: sort the unsorted partitions Date: Sun, 26 Aug 2012 07:21:39 -0000 From: Huang Shijie X-Patchwork-Id: 180025 Message-Id: <1346001700-26895-2-git-send-email-shijie8@gmail.com> To: dwmw2@infradead.org Cc: Huang Shijie , shmulik.ladkani@gmail.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, dedekind1@gmail.com Assume we have a 1GB(8Gb) nand chip. It is legit if we set the partitions as the following: gpmi-nand:1g@200m(rootfs),100m@0(boot),100m@100m(kernel) But the current code can not parse out any partition with this cmdline. This patch sorts the unsorted partitions by the @offset. For there are maybe only several partitions, i use the simple Bubble sort algorithm. Signed-off-by: Huang Shijie --- drivers/mtd/cmdlinepart.c | 29 +++++++++++++++++++++++++++++ 1 files changed, 29 insertions(+), 0 deletions(-) diff --git a/drivers/mtd/cmdlinepart.c b/drivers/mtd/cmdlinepart.c index 0b7b2ad..f40d390 100644 --- a/drivers/mtd/cmdlinepart.c +++ b/drivers/mtd/cmdlinepart.c @@ -234,6 +234,32 @@ static struct mtd_partition * newpart(char *s, return parts; } +/* There are only several partitions, so the Bubble sort is enough. */ +static inline void sort_partitons(struct mtd_partition *parts, int num_parts) +{ + int i, j; + + if (num_parts < 2) + return; + + if (parts[0].offset == OFFSET_CONTINUOUS) + return; + + /* sort by the offset */ + for (i = 0; i < num_parts - 1; i++) { + for (j = 1; j < num_parts - i; j++) { + if (parts[j - 1].offset > parts[j].offset) { + struct mtd_partition tmp; + + tmp = parts[j - 1]; + parts[j - 1] = parts[j]; + parts[j] = tmp; + } + } + } + return; +} + /* * Parse the command line. */ @@ -292,6 +318,9 @@ static int mtdpart_setup_real(char *s) this_mtd->mtd_id = (char*)(this_mtd + 1); strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1); + /* sort the partitions */ + sort_partitons(parts, num_parts); + /* link into chain */ this_mtd->next = partitions; partitions = this_mtd;