1 files changed, 138 insertions, 0 deletions
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
new file mode 100644
index 0000000000..dc2611f732
--- /dev/null
+++ b/fs/pstore/platform.c
@@ -0,0 +1,138 @@
+/*
+ * Persistent Storage - platform driver interface parts.
+ *
+ * Copyright (C) 2007-2008 Google, Inc.
+ * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ *  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.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "pstore: " fmt
+
+#include <linux/types.h>
+#include <linux/pstore.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <malloc.h>
+#include <printk.h>
+#include <module.h>
+
+#include "internal.h"
+
+struct pstore_info *psinfo;
+
+static char *backend;
+
+/* How much of the console log to snapshot */
+static unsigned long kmsg_bytes = 10240;
+
+void pstore_set_kmsg_bytes(int bytes)
+{
+	kmsg_bytes = bytes;
+}
+
+static int pstore_write_compat(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)
+{
+	return psi->write_buf(type, reason, id, part, psinfo->buf, compressed,
+			     size, psi);
+}
+
+/*
+ * platform specific persistent storage driver registers with
+ * us here. If pstore is already mounted, call the platform
+ * read function right away to populate the file system. If not
+ * then the pstore mount code will call us later to fill out
+ * the file system.
+ *
+ * Register with kmsg_dump to save last part of console log on panic.
+ */
+int pstore_register(struct pstore_info *psi)
+{
+	if (backend && strcmp(backend, psi->name))
+		return -EPERM;
+
+	spin_lock(&pstore_lock);
+	if (psinfo) {
+		spin_unlock(&pstore_lock);
+		return -EBUSY;
+	}
+
+	if (!psi->write)
+		psi->write = pstore_write_compat;
+	psinfo = psi;
+	mutex_init(&psinfo->read_mutex);
+	spin_unlock(&pstore_lock);
+
+	pstore_get_records(0);
+
+	pr_info("Registered %s as persistent store backend\n", psi->name);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pstore_register);
+
+/*
+ * Read all the records from the persistent store. Create
+ * files in our filesystem.  Don't warn about -EEXIST errors
+ * when we are re-scanning the backing store looking to add new
+ * error records.
+ */
+void pstore_get_records(int quiet)
+{
+	struct pstore_info *psi = psinfo;
+	char			*buf = NULL;
+	ssize_t			size;
+	u64			id;
+	int			count;
+	enum pstore_type_id	type;
+	int			failed = 0, rc;
+	bool			compressed;
+	int			unzipped_len = -1;
+
+	if (!psi)
+		return;
+
+	mutex_lock(&psi->read_mutex);
+	if (psi->open && psi->open(psi))
+		goto out;
+
+	while ((size = psi->read(&id, &type, &count, &buf, &compressed,
+				psi)) > 0) {
+		if (compressed && (type == PSTORE_TYPE_DMESG)) {
+			pr_err("barebox does not have ramoops compression support\n");
+			continue;
+		}
+		rc = pstore_mkfile(type, psi->name, id, count, buf,
+				  compressed, (size_t)size, psi);
+		if (unzipped_len < 0) {
+			/* Free buffer other than big oops */
+			kfree(buf);
+			buf = NULL;
+		} else
+			unzipped_len = -1;
+		if (rc && (rc != -EEXIST || !quiet))
+			failed++;
+	}
+	if (psi->close)
+		psi->close(psi);
+out:
+	mutex_unlock(&psi->read_mutex);
+
+	if (failed)
+		pr_warn("failed to load %d record(s) from '%s'\n",
+			failed, psi->name);
+}