Merge tag 'pstore-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/kees/linux

Pull pstore subsystem updates from Kees Cook:
 "This expands the supported compressors, fixes some bugs, and finally
  adds DT bindings"

* tag 'pstore-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore/ram: add Device Tree bindings
  efi-pstore: implement efivars_pstore_exit()
  pstore: drop file opened reference count
  pstore: add lzo/lz4 compression support
  pstore: Cleanup pstore_dump()
  pstore: Enable compression on normal path (again)
  ramoops: Only unregister when registered

Documentation/devicetree/bindings/misc/ramoops.txt

@@ -0,0 +1,48 @@
+Ramoops oops/panic logger
+=========================
+
+ramoops provides persistent RAM storage for oops and panics, so they can be
+recovered after a reboot. It is a backend to pstore, so this node is named
+"ramoops" after the backend, rather than "pstore" which is the subsystem.
+
+Parts of this storage may be set aside for other persistent log buffers, such
+as kernel log messages, or for optional ECC error-correction data.  The total
+size of these optional buffers must fit in the reserved region.
+
+Any remaining space will be used for a circular buffer of oops and panic
+records.  These records have a configurable size, with a size of 0 indicating
+that they should be disabled.
+
+At least one of "record-size", "console-size", "ftrace-size", or "pmsg-size"
+must be set non-zero, but are otherwise optional as listed below.
+
+
+Required properties:
+
+- compatible: must be "ramoops"
+
+- memory-region: phandle to a region of memory that is preserved between
+  reboots
+
+
+Optional properties:
+
+- ecc-size: enables ECC support and specifies ECC buffer size in bytes
+  (defaults to 0: no ECC)
+
+- record-size: maximum size in bytes of each dump done on oops/panic
+  (defaults to 0: disabled)
+
+- console-size: size in bytes of log buffer reserved for kernel messages
+  (defaults to 0: disabled)
+
+- ftrace-size: size in bytes of log buffer reserved for function tracing and
+  profiling (defaults to 0: disabled)
+
+- pmsg-size: size in bytes of log buffer reserved for userspace messages
+  (defaults to 0: disabled)
+
+- unbuffered: if present, use unbuffered mappings to map the reserved region
+  (defaults to buffered mappings)
+
+- no-dump-oops: if present, only dump panics (defaults to panics and oops)

Documentation/ramoops.txt

@@ -45,7 +45,7 @@ corrupt, but usually it is restorable.
 
 2. Setting the parameters
 
-Setting the ramoops parameters can be done in 2 different manners:
+Setting the ramoops parameters can be done in 3 different manners:
  1. Use the module parameters (which have the names of the variables described
  as before).
  For quick debugging, you can also reserve parts of memory during boot
@@ -54,7 +54,9 @@ Setting the ramoops parameters can be done in 2 different manners:
  kernel to use only the first 128 MB of memory, and place ECC-protected ramoops
  region at 128 MB boundary:
  "mem=128M ramoops.mem_address=0x8000000 ramoops.ecc=1"
- 2. Use a platform device and set the platform data. The parameters can then
+ 2. Use Device Tree bindings, as described in
+ Documentation/device-tree/bindings/misc/ramoops.txt.
+ 3. Use a platform device and set the platform data. The parameters can then
  be set through that platform data. An example of doing that is:
 
 #include <linux/pstore_ram.h>

arch/powerpc/kernel/nvram_64.c

@@ -444,7 +444,8 @@ static int nvram_pstore_write(enum pstore_type_id type,
  */
 static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
 				int *count, struct timespec *time, char **buf,
-				bool *compressed, struct pstore_info *psi)
+				bool *compressed, ssize_t *ecc_notice_size,
+				struct pstore_info *psi)
 {
 	struct oops_log_info *oops_hdr;
 	unsigned int err_type, id_no, size = 0;
@@ -545,6 +546,7 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
 			return -ENOMEM;
 		kfree(buff);
 
+		*ecc_notice_size = 0;
 		if (err_type == ERR_TYPE_KERNEL_PANIC_GZ)
 			*compressed = true;
 		else

drivers/acpi/apei/erst.c

@@ -927,7 +927,8 @@ static int erst_open_pstore(struct pstore_info *psi);
 static int erst_close_pstore(struct pstore_info *psi);
 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
 			   struct timespec *time, char **buf,
-			   bool *compressed, struct pstore_info *psi);
+			   bool *compressed, ssize_t *ecc_notice_size,
+			   struct pstore_info *psi);
 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
 		       u64 *id, unsigned int part, int count, bool compressed,
 		       size_t size, struct pstore_info *psi);
@@ -987,7 +988,8 @@ static int erst_close_pstore(struct pstore_info *psi)
 
 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
 			   struct timespec *time, char **buf,
-			   bool *compressed, struct pstore_info *psi)
+			   bool *compressed, ssize_t *ecc_notice_size,
+			   struct pstore_info *psi)
 {
 	int rc;
 	ssize_t len = 0;
@@ -1033,6 +1035,7 @@ static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
 	memcpy(*buf, rcd->data, len - sizeof(*rcd));
 	*id = record_id;
 	*compressed = false;
+	*ecc_notice_size = 0;
 	if (uuid_le_cmp(rcd->sec_hdr.section_type,
 			CPER_SECTION_TYPE_DMESG_Z) == 0) {
 		*type = PSTORE_TYPE_DMESG;

drivers/firmware/efi/efi-pstore.c

@@ -34,6 +34,7 @@ struct pstore_read_data {
 	int *count;
 	struct timespec *timespec;
 	bool *compressed;
+	ssize_t *ecc_notice_size;
 	char **buf;
 };
 
@@ -69,13 +70,15 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
 			*cb_data->compressed = true;
 		else
 			*cb_data->compressed = false;
+		*cb_data->ecc_notice_size = 0;
 	} else if (sscanf(name, "dump-type%u-%u-%d-%lu",
 		   cb_data->type, &part, &cnt, &time) == 4) {
 		*cb_data->id = generic_id(time, part, cnt);
 		*cb_data->count = cnt;
 		cb_data->timespec->tv_sec = time;
 		cb_data->timespec->tv_nsec = 0;
 		*cb_data->compressed = false;
+		*cb_data->ecc_notice_size = 0;
 	} else if (sscanf(name, "dump-type%u-%u-%lu",
 			  cb_data->type, &part, &time) == 3) {
 		/*
@@ -88,6 +91,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
 		cb_data->timespec->tv_sec = time;
 		cb_data->timespec->tv_nsec = 0;
 		*cb_data->compressed = false;
+		*cb_data->ecc_notice_size = 0;
 	} else
 		return 0;
 
@@ -210,6 +214,7 @@ static int efi_pstore_sysfs_entry_iter(void *data, struct efivar_entry **pos)
 static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
 			       int *count, struct timespec *timespec,
 			       char **buf, bool *compressed,
+			       ssize_t *ecc_notice_size,
 			       struct pstore_info *psi)
 {
 	struct pstore_read_data data;
@@ -220,6 +225,7 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
 	data.count = count;
 	data.timespec = timespec;
 	data.compressed = compressed;
+	data.ecc_notice_size = ecc_notice_size;
 	data.buf = buf;
 
 	*data.buf = kzalloc(EFIVARS_DATA_SIZE_MAX, GFP_KERNEL);
@@ -393,6 +399,13 @@ static __init int efivars_pstore_init(void)
 
 static __exit void efivars_pstore_exit(void)
 {
+	if (!efi_pstore_info.bufsize)
+		return;
+
+	pstore_unregister(&efi_pstore_info);
+	kfree(efi_pstore_info.buf);
+	efi_pstore_info.buf = NULL;
+	efi_pstore_info.bufsize = 0;
 }
 
 module_init(efivars_pstore_init);

fs/pstore/Kconfig

@@ -1,8 +1,6 @@
 config PSTORE
 	tristate "Persistent store support"
 	default n
-	select ZLIB_DEFLATE
-	select ZLIB_INFLATE
 	help
 	   This option enables generic access to platform level
 	   persistent storage via "pstore" filesystem that can
@@ -14,6 +12,35 @@ config PSTORE
 	   If you don't have a platform persistent store driver,
 	   say N.
 
+choice
+        prompt "Choose compression algorithm"
+        depends on PSTORE
+        default PSTORE_ZLIB_COMPRESS
+        help
+          This option chooses compression algorithm.
+
+config PSTORE_ZLIB_COMPRESS
+        bool "ZLIB"
+        select ZLIB_DEFLATE
+        select ZLIB_INFLATE
+        help
+          This option enables ZLIB compression algorithm support.
+
+config PSTORE_LZO_COMPRESS
+        bool "LZO"
+        select LZO_COMPRESS
+        select LZO_DECOMPRESS
+        help
+          This option enables LZO compression algorithm support.
+
+config PSTORE_LZ4_COMPRESS
+        bool "LZ4"
+        select LZ4_COMPRESS
+        select LZ4_DECOMPRESS
+        help
+          This option enables LZ4 compression algorithm support.
+endchoice
+
 config PSTORE_CONSOLE
 	bool "Log kernel console messages"
 	depends on PSTORE

fs/pstore/inode.c

@@ -178,7 +178,6 @@ static loff_t pstore_file_llseek(struct file *file, loff_t off, int whence)
 }
 
 static const struct file_operations pstore_file_operations = {
-	.owner		= THIS_MODULE,
 	.open		= pstore_file_open,
 	.read		= pstore_file_read,
 	.llseek		= pstore_file_llseek,