[PATCH -next v2 07/12] pstore/ram: Add kern-doc for struct persistent_ram_zone

From: Kees Cook
Date: Thu Nov 29 2018 - 18:09:02 EST


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

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
fs/pstore/ram_core.c | 10 +++++++++
include/linux/pstore_ram.h | 46 +++++++++++++++++++++++++++++++++++---
2 files changed, 53 insertions(+), 3 deletions(-)

diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 62830734deee..3e9e3ba4fb07 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -29,6 +29,16 @@
#include <linux/vmalloc.h>
#include <asm/page.h>

+/**
+ * struct persistent_ram_buffer - persistent circular RAM buffer
+ *
+ * @sig:
+ * signature to indicate header (PERSISTENT_RAM_SIG xor PRZ-type value)
+ * @start:
+ * offset into @data where the beginning of the stored bytes begin
+ * @size:
+ * number of valid bytes stored in @data
+ */
struct persistent_ram_buffer {
uint32_t sig;
atomic_t start;
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;
--
2.17.1