commit c7f3c595f6ff7a1cfbf7ac782722bf5173e27775
author Kees Cook <keescook@chromium.org> Fri May 19 15:29:10 2017 -0700
committer Kees Cook <keescook@chromium.org> Wed May 31 10:13:44 2017 -0700
tree 7adaa468343cb5d9a45ce738d1fee91ca22dc489
parent e581ca813a40a4ee53c862d8f6303f486c4b4c34

pstore: Populate pstore record->time field

The current time will be initially available in the record->time field
for all pstore_read() and pstore_write() calls. Backends can either
update the field during read(), or use the field during write() instead
of fetching time themselves.

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

fs/pstore/ram.c

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 5cb022c..7125b39 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -27,7 +27,6 @@
 #include <linux/module.h>
 #include <linux/version.h>
 #include <linux/pstore.h>
-#include <linux/time.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/platform_device.h>
@@ -356,20 +355,15 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
 }
 
 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
-				     bool compressed)
+				     struct pstore_record *record)
 {
 	char *hdr;
-	struct timespec timestamp;
 	size_t len;
 
-	/* Report zeroed timestamp if called before timekeeping has resumed. */
-	if (__getnstimeofday(&timestamp)) {
-		timestamp.tv_sec = 0;
-		timestamp.tv_nsec = 0;
-	}
 	hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
-		(long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000),
-		compressed ? 'C' : 'D');
+		record->time.tv_sec,
+		record->time.tv_nsec / 1000,
+		record->compressed ? 'C' : 'D');
 	WARN_ON_ONCE(!hdr);
 	len = hdr ? strlen(hdr) : 0;
 	persistent_ram_write(prz, hdr, len);
@@ -440,7 +434,7 @@ static int notrace ramoops_pstore_write(struct pstore_record *record)
 	prz = cxt->dprzs[cxt->dump_write_cnt];
 
 	/* Build header and append record contents. */
-	hlen = ramoops_write_kmsg_hdr(prz, record->compressed);
+	hlen = ramoops_write_kmsg_hdr(prz, record);
 	size = record->size;
 	if (size + hlen > prz->buffer_size)
 		size = prz->buffer_size - hlen;