Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

Pull pstore update from Tony Luck:
 "Miscellaneous fs/pstore fixes"

* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore: Fix sprintf format specifier in pstore_dump()
  pstore: Add pmsg - user-space accessible pstore object
  pstore: Handle zero-sized prz in series
  pstore: Remove superfluous memory size check
  pstore: Use scnprintf() in pstore_mkfile()

9 files changed, 193 insertions, 25 deletions

diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index 983d9510becc..916b8e23d968 100644
--- a/fs/pstore/Kconfig
+++ b/fs/pstore/Kconfig
@@ -21,6 +21,16 @@ config PSTORE_CONSOLE
           When the option is enabled, pstore will log all kernel
           messages, even if no oops or panic happened.
 
+config PSTORE_PMSG
+        bool "Log user space messages"
+        depends on PSTORE
+        help
+          When the option is enabled, pstore will export a character
+          interface /dev/pmsg0 to log user space messages. On reboot
+          data can be retrieved from /sys/fs/pstore/pmsg-ramoops-[ID].
+
+          If unsure, say N.
+
 config PSTORE_FTRACE
         bool "Persistent function tracer"
         depends on PSTORE
diff --git a/fs/pstore/Makefile b/fs/pstore/Makefile
index 4c9095c2781e..e647d8e81712 100644
--- a/fs/pstore/Makefile
+++ b/fs/pstore/Makefile
@@ -7,5 +7,7 @@ obj-y += pstore.o
 pstore-objs += inode.o platform.o
 obj-$(CONFIG_PSTORE_FTRACE)     += ftrace.o
 
+obj-$(CONFIG_PSTORE_PMSG)       += pmsg.o
+
 ramoops-objs += ram.o ram_core.o
 obj-$(CONFIG_PSTORE_RAM)        += ramoops.o
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 50416602774d..b32ce53d24ee 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -338,32 +338,38 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
 
         switch (type) {
         case PSTORE_TYPE_DMESG:
-                sprintf(name, "dmesg-%s-%lld%s", psname, id,
-                                                compressed ? ".enc.z" : "");
+                scnprintf(name, sizeof(name), "dmesg-%s-%lld%s",
+                          psname, id, compressed ? ".enc.z" : "");
                 break;
         case PSTORE_TYPE_CONSOLE:
-                sprintf(name, "console-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "console-%s-%lld", psname, id);
                 break;
         case PSTORE_TYPE_FTRACE:
-                sprintf(name, "ftrace-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "ftrace-%s-%lld", psname, id);
                 break;
         case PSTORE_TYPE_MCE:
-                sprintf(name, "mce-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "mce-%s-%lld", psname, id);
                 break;
         case PSTORE_TYPE_PPC_RTAS:
-                sprintf(name, "rtas-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "rtas-%s-%lld", psname, id);
                 break;
         case PSTORE_TYPE_PPC_OF:
-                sprintf(name, "powerpc-ofw-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "powerpc-ofw-%s-%lld",
+                          psname, id);
                 break;
         case PSTORE_TYPE_PPC_COMMON:
-                sprintf(name, "powerpc-common-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "powerpc-common-%s-%lld",
+                          psname, id);
+                break;
+        case PSTORE_TYPE_PMSG:
+                scnprintf(name, sizeof(name), "pmsg-%s-%lld", psname, id);
                 break;
         case PSTORE_TYPE_UNKNOWN:
-                sprintf(name, "unknown-%s-%lld", psname, id);
+                scnprintf(name, sizeof(name), "unknown-%s-%lld", psname, id);
                 break;
         default:
-                sprintf(name, "type%d-%s-%lld", type, psname, id);
+                scnprintf(name, sizeof(name), "type%d-%s-%lld",
+                          type, psname, id);
                 break;
         }
 
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index 3b3d305277c4..c36ba2cd0b5d 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -45,6 +45,12 @@ extern void pstore_register_ftrace(void);
 static inline void pstore_register_ftrace(void) {}
 #endif
 
+#ifdef CONFIG_PSTORE_PMSG
+extern void pstore_register_pmsg(void);
+#else
+static inline void pstore_register_pmsg(void) {}
+#endif
+
 extern struct pstore_info *psinfo;
 
 extern void     pstore_set_kmsg_bytes(int);
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 0a9b72cdfeca..c4c9a10c5760 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -301,7 +301,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
 
                 if (big_oops_buf) {
                         dst = big_oops_buf;
-                        hsize = sprintf(dst, "%s#%d Part%d\n", why,
+                        hsize = sprintf(dst, "%s#%d Part%u\n", why,
                                                         oopscount, part);
                         size = big_oops_buf_sz - hsize;
 
@@ -321,7 +321,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
                         }
                 } else {
                         dst = psinfo->buf;
-                        hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount,
+                        hsize = sprintf(dst, "%s#%d Part%u\n", why, oopscount,
                                                                         part);
                         size = psinfo->bufsize - hsize;
                         dst += hsize;
@@ -447,6 +447,7 @@ int pstore_register(struct pstore_info *psi)
         if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) {
                 pstore_register_console();
                 pstore_register_ftrace();
+                pstore_register_pmsg();
         }
 
         if (pstore_update_ms >= 0) {
diff --git a/fs/pstore/pmsg.c b/fs/pstore/pmsg.c
new file mode 100644
index 000000000000..feb5dd2948b4
--- /dev/null
+++ b/fs/pstore/pmsg.c
@@ -0,0 +1,114 @@
+/*
+ * Copyright 2014  Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include "internal.h"
+
+static DEFINE_MUTEX(pmsg_lock);
+#define PMSG_MAX_BOUNCE_BUFFER_SIZE (2*PAGE_SIZE)
+
+static ssize_t write_pmsg(struct file *file, const char __user *buf,
+                          size_t count, loff_t *ppos)
+{
+        size_t i, buffer_size;
+        char *buffer;
+
+        if (!count)
+                return 0;
+
+        if (!access_ok(VERIFY_READ, buf, count))
+                return -EFAULT;
+
+        buffer_size = count;
+        if (buffer_size > PMSG_MAX_BOUNCE_BUFFER_SIZE)
+                buffer_size = PMSG_MAX_BOUNCE_BUFFER_SIZE;
+        buffer = vmalloc(buffer_size);