pstore/ram: Add kern-doc for struct persistent_ram_zone

The struct persistent_ram_zone wasn't well documented. This adds kern-doc
for it.

Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 43 insertions, 3 deletions

diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h
index 6e94980357d2..5d10ad51c1c4 100644
--- a/include/linux/pstore_ram.h
+++ b/include/linux/pstore_ram.h
@@ -30,6 +30,10 @@
  * PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required.
  */
 #define PRZ_FLAG_NO_LOCK        BIT(0)
+/*
+ * If a PRZ should only have a single-boot lifetime, this marks it as
+ * getting wiped after its contents get copied out after boot.
+ */
 #define PRZ_FLAG_ZAP_OLD        BIT(1)
 
 struct persistent_ram_buffer;
@@ -43,17 +47,53 @@ struct persistent_ram_ecc_info {
         uint16_t *par;
 };
 
+/**
+ * struct persistent_ram_zone - Details of a persistent RAM zone (PRZ)
+ *                              used as a pstore backend
+ *
+ * @paddr:      physical address of the mapped RAM area
+ * @size:       size of mapping
+ * @label:      unique name of this PRZ
+ * @flags:      holds PRZ_FLAGS_* bits
+ *
+ * @buffer_lock:
+ *      locks access to @buffer "size" bytes and "start" offset
+ * @buffer:
+ *      pointer to actual RAM area managed by this PRZ
+ * @buffer_size:
+ *      bytes in @buffer->data (not including any trailing ECC bytes)
+ *
+ * @par_buffer:
+ *      pointer into @buffer->data containing ECC bytes for @buffer->data
+ * @par_header:
+ *      pointer into @buffer->data containing ECC bytes for @buffer header
+ *      (i.e. all fields up to @data)
+ * @rs_decoder:
+ *      RSLIB instance for doing ECC calculations
+ * @corrected_bytes:
+ *      ECC corrected bytes accounting since boot
+ * @bad_blocks:
+ *      ECC uncorrectable bytes accounting since boot
+ * @ecc_info:
+ *      ECC configuration details
+ *
+ * @old_log:
+ *      saved copy of @buffer->data prior to most recent wipe
+ * @old_log_size:
+ *      bytes contained in @old_log
+ *
+ */
 struct persistent_ram_zone {
         phys_addr_t paddr;
         size_t size;
         void *vaddr;
         char *label;
-        struct persistent_ram_buffer *buffer;
-        size_t buffer_size;
         u32 flags;
+
         raw_spinlock_t buffer_lock;
+        struct persistent_ram_buffer *buffer;
+        size_t buffer_size;
 
-        /* ECC correction */
         char *par_buffer;
         char *par_header;
         struct rs_control *rs_decoder;