powerpc/nvram: Improve partition removal

[pandora-kernel.git] / arch / powerpc / kernel / nvram_64.c

diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index eabee7c..6dd2700 100644 (file)
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -247,61 +247,54 @@ static unsigned char __init nvram_checksum(struct nvram_header *p)
        return c_sum;
 }
 
-static int __init nvram_remove_os_partition(void)
+/**
+ * nvram_remove_partition - Remove one or more partitions in nvram
+ * @name: name of the partition to remove, or NULL for a
+ *        signature only match
+ * @sig: signature of the partition(s) to remove
+ */
+
+static int __init nvram_remove_partition(const char *name, int sig)
 {
-       struct list_head *i;
-       struct list_head *j;
-       struct nvram_partition * part;
-       struct nvram_partition * cur_part;
+       struct nvram_partition *part, *prev, *tmp;
        int rc;
 
-       list_for_each(i, &nvram_part->partition) {
-               part = list_entry(i, struct nvram_partition, partition);
-               if (part->header.signature != NVRAM_SIG_OS)
+       list_for_each_entry(part, &nvram_part->partition, partition) {
+               if (part->header.signature != sig)
                        continue;
-               
-               /* Make os partition a free partition */
+               if (name && strncmp(name, part->header.name, 12))
+                       continue;
+
+               /* Make partition a free partition */
                part->header.signature = NVRAM_SIG_FREE;
                sprintf(part->header.name, "wwwwwwwwwwww");
                part->header.checksum = nvram_checksum(&part->header);
-
-               /* Merge contiguous free partitions backwards */
-               list_for_each_prev(j, &part->partition) {
-                       cur_part = list_entry(j, struct nvram_partition, partition);
-                       if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
-                               break;
-                       }
-                       
-                       part->header.length += cur_part->header.length;
-                       part->header.checksum = nvram_checksum(&part->header);
-                       part->index = cur_part->index;
-
-                       list_del(&cur_part->partition);
-                       kfree(cur_part);
-                       j = &part->partition; /* fixup our loop */
-               }
-               
-               /* Merge contiguous free partitions forwards */
-               list_for_each(j, &part->partition) {
-                       cur_part = list_entry(j, struct nvram_partition, partition);
-                       if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) {
-                               break;
-                       }
-
-                       part->header.length += cur_part->header.length;
-                       part->header.checksum = nvram_checksum(&part->header);
-
-                       list_del(&cur_part->partition);
-                       kfree(cur_part);
-                       j = &part->partition; /* fixup our loop */
-               }
-               
                rc = nvram_write_header(part);
                if (rc <= 0) {
-                       printk(KERN_ERR "nvram_remove_os_partition: nvram_write failed (%d)\n", rc);
+                       printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
                        return rc;
                }
+       }
 
+       /* Merge contiguous ones */
+       prev = NULL;
+       list_for_each_entry_safe(part, tmp, &nvram_part->partition, partition) {
+               if (part->header.signature != NVRAM_SIG_FREE) {
+                       prev = NULL;
+                       continue;
+               }
+               if (prev) {
+                       prev->header.length += part->header.length;
+                       prev->header.checksum = nvram_checksum(&part->header);
+                       rc = nvram_write_header(part);
+                       if (rc <= 0) {
+                               printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
+                               return rc;
+                       }
+                       list_del(&part->partition);
+                       kfree(part);
+               } else
+                       prev = part;
        }
        
        return 0;
@@ -484,17 +477,19 @@ static int __init nvram_setup_partition(void)
                                                NVRAM_BLOCK_LEN) - sizeof(struct err_log_info);
                        return 0;
                }
+
+               /* Found one but it's too small, remove it */
+               nvram_remove_partition("ppc64,linux", NVRAM_SIG_OS);
        }
        
        /* 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 */
-               rc = nvram_remove_os_partition();
-               if (rc)
-                       return rc;      
-               /* create a partition in this new space */
+               /* 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) {