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

Pull pstore changes from Tony Luck:
 "A big part of this is the addition of compression to the generic
  pstore layer so that all backends can use the pitiful amounts of
  storage they control more effectively.  Three other small
  fixes/cleanups too.

* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore/ram: (really) fix undefined usage of rounddown_pow_of_two
  pstore/ram: Read and write to the 'compressed' flag of pstore
  efi-pstore: Read and write to the 'compressed' flag of pstore
  erst: Read and write to the 'compressed' flag of pstore
  powerpc/pseries: Read and write to the 'compressed' flag of pstore
  pstore: Add file extension to pstore file if compressed
  pstore: Add decompression support to pstore
  pstore: Introduce new argument 'compressed' in the read callback
  pstore: Add compression support to pstore
  pstore/Kconfig: Select ZLIB_DEFLATE and ZLIB_INFLATE when PSTORE is selected
  pstore: Add new argument 'compressed' in pstore write callback
  powerpc/pseries: Remove (de)compression in nvram with pstore enabled
  pstore: d_alloc_name() doesn't return an ERR_PTR
  acpi/apei/erst: Add missing iounmap() on error in erst_exec_move_data()

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index 88d0b0f9f92..822b1ed3b00 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -284,8 +284,10 @@ static int erst_exec_move_data(struct apei_exec_context *ctx,
 	if (!src)
 		return -ENOMEM;
 	dst = ioremap(ctx->dst_base + offset, ctx->var2);
-	if (!dst)
+	if (!dst) {
+		iounmap(src);
 		return -ENOMEM;
+	}
 
 	memmove(dst, src, ctx->var2);
 
@@ -933,9 +935,9 @@ 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,
-			   struct pstore_info *psi);
+			   bool *compressed, 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, size_t hsize,
+		       u64 *id, unsigned int part, int count, bool compressed,
 		       size_t size, struct pstore_info *psi);
 static int erst_clearer(enum pstore_type_id type, u64 id, int count,
 			struct timespec time, struct pstore_info *psi);
@@ -956,6 +958,9 @@ static struct pstore_info erst_info = {
 #define CPER_SECTION_TYPE_DMESG						\
 	UUID_LE(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54,	\
 		0x94, 0x19, 0xeb, 0x12)
+#define CPER_SECTION_TYPE_DMESG_Z					\
+	UUID_LE(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d,	\
+		0x34, 0xdd, 0xfa, 0xc6)
 #define CPER_SECTION_TYPE_MCE						\
 	UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96,	\
 		0x04, 0x4a, 0x38, 0xfc)
@@ -989,7 +994,7 @@ 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,
-			   struct pstore_info *psi)
+			   bool *compressed, struct pstore_info *psi)
 {
 	int rc;
 	ssize_t len = 0;
@@ -1034,7 +1039,12 @@ skip:
 	}
 	memcpy(*buf, rcd->data, len - sizeof(*rcd));
 	*id = record_id;
+	*compressed = false;
 	if (uuid_le_cmp(rcd->sec_hdr.section_type,
+			CPER_SECTION_TYPE_DMESG_Z) == 0) {
+		*type = PSTORE_TYPE_DMESG;
+		*compressed = true;
+	} else if (uuid_le_cmp(rcd->sec_hdr.section_type,
 			CPER_SECTION_TYPE_DMESG) == 0)
 		*type = PSTORE_TYPE_DMESG;
 	else if (uuid_le_cmp(rcd->sec_hdr.section_type,
@@ -1055,7 +1065,7 @@ out:
 }
 
 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
-		       u64 *id, unsigned int part, int count, size_t hsize,
+		       u64 *id, unsigned int part, int count, bool compressed,
 		       size_t size, struct pstore_info *psi)
 {
 	struct cper_pstore_record *rcd = (struct cper_pstore_record *)
@@ -1085,7 +1095,10 @@ static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
 	rcd->sec_hdr.flags = CPER_SEC_PRIMARY;
 	switch (type) {
 	case PSTORE_TYPE_DMESG:
-		rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;
+		if (compressed)
+			rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z;
+		else
+			rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;
 		break;
 	case PSTORE_TYPE_MCE:
 		rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE;