block/partitions: optimize memory allocation in check_partition()

[karo-tx-linux.git] / block / partitions / check.c

diff --git a/block/partitions/check.c b/block/partitions/check.c
index bc908672c9764ca782f1e575825c1495e11a6ab4..19ba207ea7d12de48ae0a6182c71df3d188c2b3a 100644 (file)
--- a/block/partitions/check.c
+++ b/block/partitions/check.c
@@ -14,6 +14,7 @@
  */
 
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
 #include <linux/ctype.h>
 #include <linux/genhd.h>
 
@@ -106,18 +107,45 @@ static int (*check_part[])(struct parsed_partitions *) = {
        NULL
 };
 
+static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
+{
+       struct parsed_partitions *state;
+       int nr;
+
+       state = kzalloc(sizeof(*state), GFP_KERNEL);
+       if (!state)
+               return NULL;
+
+       nr = disk_max_parts(hd);
+       state->parts = vzalloc(nr * sizeof(state->parts[0]));
+       if (!state->parts) {
+               kfree(state);
+               return NULL;
+       }
+
+       state->limit = nr;
+
+       return state;
+}
+
+void free_partitions(struct parsed_partitions *state)
+{
+       vfree(state->parts);
+       kfree(state);
+}
+
 struct parsed_partitions *
 check_partition(struct gendisk *hd, struct block_device *bdev)
 {
        struct parsed_partitions *state;
        int i, res, err;
 
-       state = kzalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
+       state = allocate_partitions(hd);
        if (!state)
                return NULL;
        state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
        if (!state->pp_buf) {
-               kfree(state);
+               free_partitions(state);
                return NULL;
        }
        state->pp_buf[0] = '\0';
@@ -128,10 +156,9 @@ check_partition(struct gendisk *hd, struct block_device *bdev)
        if (isdigit(state->name[strlen(state->name)-1]))
                sprintf(state->name, "p");
 
-       state->limit = disk_max_parts(hd);
        i = res = err = 0;
        while (!res && check_part[i]) {
-               memset(&state->parts, 0, sizeof(state->parts));
+               memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
                res = check_part[i++](state);
                if (res < 0) {
                        /* We have hit an I/O error which we don't report now.
@@ -161,6 +188,6 @@ check_partition(struct gendisk *hd, struct block_device *bdev)
        printk(KERN_INFO "%s", state->pp_buf);
 
        free_page((unsigned long)state->pp_buf);
-       kfree(state);
+       free_partitions(state);
        return ERR_PTR(res);
 }