powerpc/nvram: Change nvram_setup_partition() to use new helper

This changes the function to use nvram_find_partition() instead
of doing the lookup "by hand". It also makes some of the logic
clearer and prints out more useful diagnostic information.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 32 insertions, 39 deletions

diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 01e6844be8d7..76f546b9944d 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -469,9 +469,8 @@ loff_t nvram_find_partition(const char *name, int sig, int *out_size)
  */
 static int __init nvram_setup_partition(void)
 {
-        struct list_head * p;
-        struct nvram_partition * part;
-        int rc;
+        loff_t p;
+        int size;
 
         /* For now, we don't do any of this on pmac, until I
          * have figured out if it's worth killing some unused stuffs
@@ -481,48 +480,42 @@ static int __init nvram_setup_partition(void)
         if (machine_is(powermac))
                 return -ENOSPC;
 
-        /* see if we have an OS partition that meets our needs.
-           will try getting the max we need.  If not we'll delete
-           partitions and try again. */
-        list_for_each(p, &nvram_part->partition) {
-                part = list_entry(p, struct nvram_partition, partition);
-                if (part->header.signature != NVRAM_SIG_OS)
-                        continue;
-
-                if (strcmp(part->header.name, "ppc64,linux"))
-                        continue;
-
-                if ((part->header.length - 1) * NVRAM_BLOCK_LEN >= NVRAM_MIN_REQ) {
-                        /* found our partition */
-                        nvram_error_log_index = part->index + NVRAM_HEADER_LEN;
-                        nvram_error_log_size = ((part->header.length - 1) *
-                                                NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
-                        return 0;
-                }
+        p = nvram_find_partition("ppc64,linux", NVRAM_SIG_OS, &size);
 
-                /* Found one but it's too small, remove it */
+        /* Found one but too small, remove it */
+        if (p && size < NVRAM_MIN_REQ) {
+                pr_info("nvram: Found too small ppc64,linux partition"
+                        ",removing it...");
                 nvram_remove_partition("ppc64,linux", NVRAM_SIG_OS);
+                p = 0;
         }
-        
-        /* try creating a partition with the free space we have */
-        rc = nvram_create_partition("ppc64,linux", NVRAM_SIG_OS,
-                                       NVRAM_MAX_REQ, NVRAM_MIN_REQ);
-        if (rc < 0) {
-                /* need to free up some space, remove any "OS" partition */
-                nvram_remove_partition(NULL, NVRAM_SIG_OS);
-        
-                /* Try again */
-                rc = nvram_create_partition("ppc64,linux", NVRAM_SIG_OS,
-                                            NVRAM_MAX_REQ, NVRAM_MIN_REQ);
-                if (rc < 0) {
-                        pr_err("nvram_create_partition: Could not find"
-                               " enough space in NVRAM for partition\n");
-                        return rc;
+
+        /* Create one if we didn't find */
+        if (!p) {
+                p = nvram_create_partition("ppc64,linux", NVRAM_SIG_OS,
+                                           NVRAM_MAX_REQ, NVRAM_MIN_REQ);
+                /* No room for it, try to get rid of any OS partition
+                 * and try again
+                 */
+                if (p == -ENOSPC) {
+                        pr_info("nvram: No room to create ppc64,linux"
+                                " partition, deleting all OS partitions...");
+                        nvram_remove_partition(NULL, NVRAM_SIG_OS);
+                        p = nvram_create_partition("ppc64,linux", NVRAM_SIG_OS,
+                                                   NVRAM_MAX_REQ, NVRAM_MIN_REQ);
                 }
         }
+
+        if (p <= 0) {
+                pr_err("nvram: Failed to find or create ppc64,linux"
+                       " partition, err %d\n", (int)p);
+                return 0;
+        }
+
+        nvram_error_log_index = p;
+        nvram_error_log_size = nvram_get_partition_size(p) -
+                sizeof(struct err_log_info);
         
-        nvram_error_log_index = rc;     
-        nvram_error_log_size = nvram_get_partition_size(rc) - sizeof(struct err_log_info);      
         return 0;
 }