errorlog: Simplify log calling convention

Remove the callback functionality from log_error() and replace it with
the ability to append to a user data section, or add addtional user
data sections to an error log.

For multiline or otherwise complex logging the convention is now to call
opal_elog_create() to obtain a errorlog buffer and use log_append_msg()
and log_append_data() to append to the user data section. Additional
user data sections can be added to the error log via log_add_section().
The caller is then responsible for calling log_commit().

For simple logs log_simple_error() takes care of creating and committing
the error log as before.

Signed-off-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

3 files changed, 109 insertions, 68 deletions

diff --git a/core/errorlog.c b/core/errorlog.c
index d0ca71fd..7afd16ce 100644
--- a/core/errorlog.c
+++ b/core/errorlog.c
@@ -59,35 +59,8 @@ static struct errorlog *get_write_buffer(int opal_event_severity)
 	return buf;
 }
 
-int opal_elog_update_user_dump(struct errorlog *buf, unsigned char *data,
-					      uint32_t tag, uint16_t size)
-{
-	char *buffer;
-	struct elog_user_data_section *tmp;
-
-	if (!buf) {
-		prerror("ELOG: Cannot update user data. Buffer is invalid\n");
-		return -1;
-	}
-
-	buffer = (char *)buf->user_data_dump + buf->user_section_size;
-	if ((buf->user_section_size + size) > OPAL_LOG_MAX_DUMP) {
-		prerror("ELOG: Size of dump data overruns buffer\n");
-		return -1;
-	}
-
-	tmp = (struct elog_user_data_section *)buffer;
-	tmp->tag = tag;
-	tmp->size = size + sizeof(struct elog_user_data_section) - 1;
-	memcpy(tmp->data_dump, data, size);
-
-	buf->user_section_size += tmp->size;
-	buf->user_section_count++;
-	return 0;
-}
-
 /* Reporting of error via struct errorlog */
-struct errorlog *opal_elog_create(struct opal_err_info *e_info)
+struct errorlog *opal_elog_create(struct opal_err_info *e_info, uint32_t tag)
 {
 	struct errorlog *buf;
 
@@ -104,11 +77,41 @@ struct errorlog *opal_elog_create(struct opal_err_info *e_info)
 		lock(&elog_lock);
 		buf->plid = ++sapphire_elog_id;
 		unlock(&elog_lock);
+
+		/* Initialise the first user dump section */
+		log_add_section(buf, tag);
 	}
 
 	return buf;
 }
 
+/* Add a new user data section to an existing error log */
+void log_add_section(struct errorlog *buf, uint32_t tag)
+{
+	size_t size = sizeof(struct elog_user_data_section) - 1;
+	struct elog_user_data_section *tmp;
+
+	if (!buf) {
+		prerror("ELOG: Cannot add user data section. "
+			"Buffer is invalid\n");
+		return;
+	}
+
+	if ((buf->user_section_size + size) > OPAL_LOG_MAX_DUMP) {
+		prerror("ELOG: Size of dump data overruns buffer\n");
+		return;
+	}
+
+	tmp = (struct elog_user_data_section *)(buf->user_data_dump +
+						buf->user_section_size);
+	/* Use DESC if no other tag provided */
+	tmp->tag = tag ? tag : 0x44455343;
+	tmp->size = size;
+
+	buf->user_section_size += tmp->size;
+	buf->user_section_count++;
+}
+
 void opal_elog_complete(struct errorlog *buf, bool success)
 {
 	if (!success)
@@ -119,10 +122,13 @@ void opal_elog_complete(struct errorlog *buf, bool success)
 	unlock(&elog_lock);
 }
 
-static void elog_commit(struct errorlog *elog)
+void log_commit(struct errorlog *elog)
 {
 	int rc;
 
+	if (!elog)
+		return;
+
 	if (platform.elog_commit) {
 		rc = platform.elog_commit(elog);
 		if (rc)
@@ -132,13 +138,53 @@ static void elog_commit(struct errorlog *elog)
 	opal_elog_complete(elog, false);
 }
 
-void log_error(struct opal_err_info *e_info, void *data, uint16_t size,
-	       const char *fmt, ...)
+void log_append_data(struct errorlog *buf, unsigned char *data, uint16_t size)
+{
+	struct elog_user_data_section *section;
+	uint8_t n_sections;
+	char *buffer;
+
+	if (!buf) {
+		prerror("ELOG: Cannot update user data. Buffer is invalid\n");
+		return;
+	}
+
+	if ((buf->user_section_size + size) > OPAL_LOG_MAX_DUMP) {
+		prerror("ELOG: Size of dump data overruns buffer\n");
+		return;
+	}
+
+	/* Step through user sections to find latest dump section */
+	buffer = buf->user_data_dump;
+	n_sections = buf->user_section_count;
+
+	if (!n_sections) {
+		prerror("ELOG: User section invalid\n");
+		return;
+	}
+
+	while (--n_sections) {
+		section = (struct elog_user_data_section *)buffer;
+		buffer += section->size;
+	}
+
+	section = (struct elog_user_data_section *)buffer;
+	buffer += section->size;
+	memcpy(buffer, data, size);
+
+	section->size += size;
+	buf->user_section_size += size;
+}
+
+void log_append_msg(struct errorlog *buf, const char *fmt, ...)
 {
-	struct errorlog *buf;
-	int tag = 0x44455343;  /* ASCII of DESC */
-	va_list list;
 	char err_msg[250];
+	va_list list;
+
+	if (!buf) {
+		prerror("Tried to append log to NULL buffer\n");
+		return;
+	}
 
 	va_start(list, fmt);
 	vsnprintf(err_msg, sizeof(err_msg), fmt, list);
@@ -147,22 +193,12 @@ void log_error(struct opal_err_info *e_info, void *data, uint16_t size,
 	/* Log the error on to Sapphire console */
 	prerror("%s", err_msg);
 
-	buf = opal_elog_create(e_info);
-	if (buf == NULL)
-		prerror("ELOG: Error getting buffer to log error\n");
-	else {
-		opal_elog_update_user_dump(buf, err_msg, tag, strlen(err_msg));
-		/* Append any number of call out dumps */
-		if (e_info->call_out)
-			e_info->call_out(buf, data, size);
-		elog_commit(buf);
-	}
+	log_append_data(buf, err_msg, strlen(err_msg));
 }
 
 void log_simple_error(struct opal_err_info *e_info, const char *fmt, ...)
 {
 	struct errorlog *buf;
-	int tag = 0x44455343;  /* ASCII of DESC */
 	va_list list;
 	char err_msg[250];
 
@@ -173,12 +209,12 @@ void log_simple_error(struct opal_err_info *e_info, const char *fmt, ...)
 	/* Log the error on to Sapphire console */
 	prerror("%s", err_msg);
 
-	buf = opal_elog_create(e_info);
+	buf = opal_elog_create(e_info, 0);
 	if (buf == NULL)
 		prerror("ELOG: Error getting buffer to log error\n");
 	else {
-		opal_elog_update_user_dump(buf, err_msg, tag, strlen(err_msg));
-		elog_commit(buf);
+		log_append_data(buf, err_msg, strlen(err_msg));
+		log_commit(buf);
 	}
 }
 
diff --git a/hw/fsp/fsp-mem-err.c b/hw/fsp/fsp-mem-err.c
index 3eaa1a39..a4b45fc5 100644
--- a/hw/fsp/fsp-mem-err.c
+++ b/hw/fsp/fsp-mem-err.c
@@ -41,20 +41,13 @@ static LIST_HEAD(mem_error_list);
  */
 static struct lock mem_err_lock = LOCK_UNLOCKED;
 
-static void mem_err_info_dump(struct errorlog *buf, void *data, uint16_t size);
-
 DEFINE_LOG_ENTRY(OPAL_RC_MEM_ERR_RES, OPAL_PLATFORM_ERR_EVT, OPAL_MEM_ERR,
 			OPAL_MISC_SUBSYSTEM, OPAL_PREDICTIVE_ERR_GENERAL,
-			OPAL_NA, mem_err_info_dump);
+			OPAL_NA, NULL);
 
 DEFINE_LOG_ENTRY(OPAL_RC_MEM_ERR_DEALLOC, OPAL_PLATFORM_ERR_EVT, OPAL_MEM_ERR,
 			OPAL_MISC_SUBSYSTEM, OPAL_PREDICTIVE_ERR_GENERAL,
-			OPAL_NA, mem_err_info_dump);
-
-static void mem_err_info_dump(struct errorlog *buf, void *data, uint16_t size)
-{
-	opal_elog_update_user_dump(buf, data, 0x44455350, size);
-}
+			OPAL_NA, NULL);
 
 static bool send_response_to_fsp(u32 cmd_sub_mod)
 {
@@ -192,6 +185,7 @@ static bool handle_memory_resilience(u32 cmd_sub_mod, u64 paddr)
 {
 	int rc = 0;
 	struct OpalMemoryErrorData mem_err_evt;
+	struct errorlog *buf;
 
 	memset(&mem_err_evt, 0, sizeof(struct OpalMemoryErrorData));
 	/* Check arguments */
@@ -243,10 +237,14 @@ send_response:
 	if (!rc)
 		return send_response_to_fsp(FSP_RSP_MEM_RES);
 	else {
-		log_error(&e_info(OPAL_RC_MEM_ERR_RES),
-			&mem_err_evt, sizeof(struct OpalMemoryErrorData),
+		buf = opal_elog_create(&e_info(OPAL_RC_MEM_ERR_RES), 0);
+		log_append_msg(buf,
 			"OPAL_MEM_ERR: Cannot queue up memory "
 			"resilience error event to the OS");
+		log_add_section(buf, 0x44455350);
+		log_append_data(buf, (char *) &mem_err_evt,
+					   sizeof(struct OpalMemoryErrorData));
+		log_commit(buf);
 		return false;
 	}
 }
@@ -290,6 +288,7 @@ static bool handle_memory_deallocation(u64 paddr_start, u64 paddr_end)
 	int rc = 0;
 	u8 err = 0;
 	struct OpalMemoryErrorData mem_err_evt;
+	struct errorlog *buf;
 
 	memset(&mem_err_evt, 0, sizeof(struct OpalMemoryErrorData));
 	/* Check arguments */
@@ -327,10 +326,14 @@ send_response:
 	if (!rc)
 		return send_response_to_fsp(FSP_RSP_MEM_DYN_DEALLOC);
 	else {
-		log_error(&e_info(OPAL_RC_MEM_ERR_DEALLOC),
-			&mem_err_evt, sizeof(struct OpalMemoryErrorData),
+		buf = opal_elog_create(&e_info(OPAL_RC_MEM_ERR_DEALLOC), 0);
+		log_append_msg(buf,
 			"OPAL_MEM_ERR: Cannot queue up memory "
 			"deallocation error event to the OS");
+		log_add_section(buf, 0x44455350);
+		log_append_data(buf, (char *)&mem_err_evt,
+					   sizeof(struct OpalMemoryErrorData));
+		log_commit(buf);
 		return false;
 	}
 }
diff --git a/include/errorlog.h b/include/errorlog.h
index af9b4412..eb374523 100644
--- a/include/errorlog.h
+++ b/include/errorlog.h
@@ -335,16 +335,18 @@ severity, subtype, callout_func) static struct opal_err_info err_##reason =	\
  * and commits the error to FSP.
  * Used for simple error logging
  */
-void log_simple_error(struct opal_err_info *e_info, const char *fmt, ...) __attribute__ ((format (printf, 2, 3)));
-void log_error(struct opal_err_info *e_info, void *data, uint16_t size,
-		const char *fmt, ...) __attribute__ ((format (printf, 4, 5)));
+void log_simple_error(struct opal_err_info *e_info,
+		const char *fmt, ...) __attribute__ ((format (printf, 2, 3)));
 
 #define e_info(reason_code) err_##reason_code
 
-struct errorlog *opal_elog_create(struct opal_err_info *e_info) __warn_unused_result;
-
-int opal_elog_update_user_dump(struct errorlog *buf, unsigned char *data,
-						uint32_t tag, uint16_t size);
+struct errorlog *opal_elog_create(struct opal_err_info *e_info,
+				  uint32_t tag) __warn_unused_result;
+void log_add_section(struct errorlog *buf, uint32_t tag);
+void log_append_data(struct errorlog *buf, unsigned char *data, uint16_t size);
+void log_append_msg(struct errorlog *buf,
+		const char *fmt, ...) __attribute__ ((format (printf, 2, 3)));
+void log_commit(struct errorlog *elog);
 
 /* Called by the backend after an error has been logged by the
  * backend. If the error could not be logged successfully success is