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-rw-r--r--fs/pstore/platform.c827
1 files changed, 827 insertions, 0 deletions
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
new file mode 100644
index 000000000..904c2a60f
--- /dev/null
+++ b/fs/pstore/platform.c
@@ -0,0 +1,827 @@
+/*
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#define pr_fmt(fmt) "pstore: " fmt
+
+#include <linux/atomic.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kmsg_dump.h>
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/pstore.h>
+#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
+#include <linux/lzo.h>
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
+#include <linux/lz4.h>
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+#include <linux/zstd.h>
+#endif
+#include <linux/crypto.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/jiffies.h>
+#include <linux/workqueue.h>
+
+#include "internal.h"
+
+/*
+ * We defer making "oops" entries appear in pstore - see
+ * whether the system is actually still running well enough
+ * to let someone see the entry
+ */
+static int pstore_update_ms = -1;
+module_param_named(update_ms, pstore_update_ms, int, 0600);
+MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content "
+ "(default is -1, which means runtime updates are disabled; "
+ "enabling this option is not safe, it may lead to further "
+ "corruption on Oopses)");
+
+static int pstore_new_entry;
+
+static void pstore_timefunc(struct timer_list *);
+static DEFINE_TIMER(pstore_timer, pstore_timefunc);
+
+static void pstore_dowork(struct work_struct *);
+static DECLARE_WORK(pstore_work, pstore_dowork);
+
+/*
+ * pstore_lock just protects "psinfo" during
+ * calls to pstore_register()
+ */
+static DEFINE_SPINLOCK(pstore_lock);
+struct pstore_info *psinfo;
+
+static char *backend;
+static char *compress =
+#ifdef CONFIG_PSTORE_COMPRESS_DEFAULT
+ CONFIG_PSTORE_COMPRESS_DEFAULT;
+#else
+ NULL;
+#endif
+
+/* Compression parameters */
+static struct crypto_comp *tfm;
+
+struct pstore_zbackend {
+ int (*zbufsize)(size_t size);
+ const char *name;
+};
+
+static char *big_oops_buf;
+static size_t big_oops_buf_sz;
+
+/* How much of the console log to snapshot */
+unsigned long kmsg_bytes = PSTORE_DEFAULT_KMSG_BYTES;
+
+void pstore_set_kmsg_bytes(int bytes)
+{
+ kmsg_bytes = bytes;
+}
+
+/* Tag each group of saved records with a sequence number */
+static int oopscount;
+
+static const char *get_reason_str(enum kmsg_dump_reason reason)
+{
+ switch (reason) {
+ case KMSG_DUMP_PANIC:
+ return "Panic";
+ case KMSG_DUMP_OOPS:
+ return "Oops";
+ case KMSG_DUMP_EMERG:
+ return "Emergency";
+ case KMSG_DUMP_RESTART:
+ return "Restart";
+ case KMSG_DUMP_HALT:
+ return "Halt";
+ case KMSG_DUMP_POWEROFF:
+ return "Poweroff";
+ default:
+ return "Unknown";
+ }
+}
+
+/*
+ * Should pstore_dump() wait for a concurrent pstore_dump()? If
+ * not, the current pstore_dump() will report a failure to dump
+ * and return.
+ */
+static bool pstore_cannot_wait(enum kmsg_dump_reason reason)
+{
+ /* In NMI path, pstore shouldn't block regardless of reason. */
+ if (in_nmi())
+ return true;
+
+ switch (reason) {
+ /* In panic case, other cpus are stopped by smp_send_stop(). */
+ case KMSG_DUMP_PANIC:
+ /* Emergency restart shouldn't be blocked. */
+ case KMSG_DUMP_EMERG:
+ return true;
+ default:
+ return false;
+ }
+}
+
+#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
+static int zbufsize_deflate(size_t size)
+{
+ size_t cmpr;
+
+ switch (size) {
+ /* buffer range for efivars */
+ case 1000 ... 2000:
+ cmpr = 56;
+ break;
+ case 2001 ... 3000:
+ cmpr = 54;
+ break;
+ case 3001 ... 3999:
+ cmpr = 52;
+ break;
+ /* buffer range for nvram, erst */
+ case 4000 ... 10000:
+ cmpr = 45;
+ break;
+ default:
+ cmpr = 60;
+ break;
+ }
+
+ return (size * 100) / cmpr;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
+static int zbufsize_lzo(size_t size)
+{
+ return lzo1x_worst_compress(size);
+}
+#endif
+
+#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
+static int zbufsize_lz4(size_t size)
+{
+ return LZ4_compressBound(size);
+}
+#endif
+
+#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
+static int zbufsize_842(size_t size)
+{
+ return size;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+static int zbufsize_zstd(size_t size)
+{
+ return ZSTD_compressBound(size);
+}
+#endif
+
+static const struct pstore_zbackend *zbackend __ro_after_init;
+
+static const struct pstore_zbackend zbackends[] = {
+#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
+ {
+ .zbufsize = zbufsize_deflate,
+ .name = "deflate",
+ },
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
+ {
+ .zbufsize = zbufsize_lzo,
+ .name = "lzo",
+ },
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS)
+ {
+ .zbufsize = zbufsize_lz4,
+ .name = "lz4",
+ },
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
+ {
+ .zbufsize = zbufsize_lz4,
+ .name = "lz4hc",
+ },
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
+ {
+ .zbufsize = zbufsize_842,
+ .name = "842",
+ },
+#endif
+#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
+ {
+ .zbufsize = zbufsize_zstd,
+ .name = "zstd",
+ },
+#endif
+ { }
+};
+
+static int pstore_compress(const void *in, void *out,
+ unsigned int inlen, unsigned int outlen)
+{
+ int ret;
+
+ if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS))
+ return -EINVAL;
+
+ ret = crypto_comp_compress(tfm, in, inlen, out, &outlen);
+ if (ret) {
+ pr_err("crypto_comp_compress failed, ret = %d!\n", ret);
+ return ret;
+ }
+
+ return outlen;
+}
+
+static int pstore_decompress(void *in, void *out,
+ unsigned int inlen, unsigned int outlen)
+{
+ int ret;
+
+ ret = crypto_comp_decompress(tfm, in, inlen, out, &outlen);
+ if (ret) {
+ pr_err("crypto_comp_decompress failed, ret = %d!\n", ret);
+ return ret;
+ }
+
+ return outlen;
+}
+
+static void allocate_buf_for_compression(void)
+{
+ struct crypto_comp *ctx;
+ int size;
+ char *buf;
+
+ /* Skip if not built-in or compression backend not selected yet. */
+ if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend)
+ return;
+
+ /* Skip if no pstore backend yet or compression init already done. */
+ if (!psinfo || tfm)
+ return;
+
+ if (!crypto_has_comp(zbackend->name, 0, 0)) {
+ pr_err("Unknown compression: %s\n", zbackend->name);
+ return;
+ }
+
+ size = zbackend->zbufsize(psinfo->bufsize);
+ if (size <= 0) {
+ pr_err("Invalid compression size for %s: %d\n",
+ zbackend->name, size);
+ return;
+ }
+
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf) {
+ pr_err("Failed %d byte compression buffer allocation for: %s\n",
+ size, zbackend->name);
+ return;
+ }
+
+ ctx = crypto_alloc_comp(zbackend->name, 0, 0);
+ if (IS_ERR_OR_NULL(ctx)) {
+ kfree(buf);
+ pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name,
+ PTR_ERR(ctx));
+ return;
+ }
+
+ /* A non-NULL big_oops_buf indicates compression is available. */
+ tfm = ctx;
+ big_oops_buf_sz = size;
+ big_oops_buf = buf;
+
+ pr_info("Using compression: %s\n", zbackend->name);
+}
+
+static void free_buf_for_compression(void)
+{
+ if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && tfm) {
+ crypto_free_comp(tfm);
+ tfm = NULL;
+ }
+ kfree(big_oops_buf);
+ big_oops_buf = NULL;
+ big_oops_buf_sz = 0;
+}
+
+/*
+ * Called when compression fails, since the printk buffer
+ * would be fetched for compression calling it again when
+ * compression fails would have moved the iterator of
+ * printk buffer which results in fetching old contents.
+ * Copy the recent messages from big_oops_buf to psinfo->buf
+ */
+static size_t copy_kmsg_to_buffer(int hsize, size_t len)
+{
+ size_t total_len;
+ size_t diff;
+
+ total_len = hsize + len;
+
+ if (total_len > psinfo->bufsize) {
+ diff = total_len - psinfo->bufsize + hsize;
+ memcpy(psinfo->buf, big_oops_buf, hsize);
+ memcpy(psinfo->buf + hsize, big_oops_buf + diff,
+ psinfo->bufsize - hsize);
+ total_len = psinfo->bufsize;
+ } else
+ memcpy(psinfo->buf, big_oops_buf, total_len);
+
+ return total_len;
+}
+
+void pstore_record_init(struct pstore_record *record,
+ struct pstore_info *psinfo)
+{
+ memset(record, 0, sizeof(*record));
+
+ record->psi = psinfo;
+
+ /* Report zeroed timestamp if called before timekeeping has resumed. */
+ record->time = ns_to_timespec64(ktime_get_real_fast_ns());
+}
+
+/*
+ * callback from kmsg_dump. (s2,l2) has the most recently
+ * written bytes, older bytes are in (s1,l1). Save as much
+ * as we can from the end of the buffer.
+ */
+static void pstore_dump(struct kmsg_dumper *dumper,
+ enum kmsg_dump_reason reason)
+{
+ unsigned long total = 0;
+ const char *why;
+ unsigned int part = 1;
+ int ret;
+
+ why = get_reason_str(reason);
+
+ if (down_trylock(&psinfo->buf_lock)) {
+ /* Failed to acquire lock: give up if we cannot wait. */
+ if (pstore_cannot_wait(reason)) {
+ pr_err("dump skipped in %s path: may corrupt error record\n",
+ in_nmi() ? "NMI" : why);
+ return;
+ }
+ if (down_interruptible(&psinfo->buf_lock)) {
+ pr_err("could not grab semaphore?!\n");
+ return;
+ }
+ }
+
+ oopscount++;
+ while (total < kmsg_bytes) {
+ char *dst;
+ size_t dst_size;
+ int header_size;
+ int zipped_len = -1;
+ size_t dump_size;
+ struct pstore_record record;
+
+ pstore_record_init(&record, psinfo);
+ record.type = PSTORE_TYPE_DMESG;
+ record.count = oopscount;
+ record.reason = reason;
+ record.part = part;
+ record.buf = psinfo->buf;
+
+ if (big_oops_buf) {
+ dst = big_oops_buf;
+ dst_size = big_oops_buf_sz;
+ } else {
+ dst = psinfo->buf;
+ dst_size = psinfo->bufsize;
+ }
+
+ /* Write dump header. */
+ header_size = snprintf(dst, dst_size, "%s#%d Part%u\n", why,
+ oopscount, part);
+ dst_size -= header_size;
+
+ /* Write dump contents. */
+ if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
+ dst_size, &dump_size))
+ break;
+
+ if (big_oops_buf) {
+ zipped_len = pstore_compress(dst, psinfo->buf,
+ header_size + dump_size,
+ psinfo->bufsize);
+
+ if (zipped_len > 0) {
+ record.compressed = true;
+ record.size = zipped_len;
+ } else {
+ record.size = copy_kmsg_to_buffer(header_size,
+ dump_size);
+ }
+ } else {
+ record.size = header_size + dump_size;
+ }
+
+ ret = psinfo->write(&record);
+ if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
+ pstore_new_entry = 1;
+
+ total += record.size;
+ part++;
+ }
+
+ up(&psinfo->buf_lock);
+}
+
+static struct kmsg_dumper pstore_dumper = {
+ .dump = pstore_dump,
+};
+
+/*
+ * Register with kmsg_dump to save last part of console log on panic.
+ */
+static void pstore_register_kmsg(void)
+{
+ kmsg_dump_register(&pstore_dumper);
+}
+
+static void pstore_unregister_kmsg(void)
+{
+ kmsg_dump_unregister(&pstore_dumper);
+}
+
+#ifdef CONFIG_PSTORE_CONSOLE
+static void pstore_console_write(struct console *con, const char *s, unsigned c)
+{
+ struct pstore_record record;
+
+ pstore_record_init(&record, psinfo);
+ record.type = PSTORE_TYPE_CONSOLE;
+
+ record.buf = (char *)s;
+ record.size = c;
+ psinfo->write(&record);
+}
+
+static struct console pstore_console = {
+ .name = "pstore",
+ .write = pstore_console_write,
+ .flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME,
+ .index = -1,
+};
+
+static void pstore_register_console(void)
+{
+ register_console(&pstore_console);
+}
+
+static void pstore_unregister_console(void)
+{
+ unregister_console(&pstore_console);
+}
+#else
+static void pstore_register_console(void) {}
+static void pstore_unregister_console(void) {}
+#endif
+
+static int pstore_write_user_compat(struct pstore_record *record,
+ const char __user *buf)
+{
+ int ret = 0;
+
+ if (record->buf)
+ return -EINVAL;
+
+ record->buf = memdup_user(buf, record->size);
+ if (IS_ERR(record->buf)) {
+ ret = PTR_ERR(record->buf);
+ goto out;
+ }
+
+ ret = record->psi->write(record);
+
+ kfree(record->buf);
+out:
+ record->buf = NULL;
+
+ return unlikely(ret < 0) ? ret : record->size;
+}
+
+/*
+ * 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.
+ */
+int pstore_register(struct pstore_info *psi)
+{
+ struct module *owner = psi->owner;
+
+ if (backend && strcmp(backend, psi->name)) {
+ pr_warn("ignoring unexpected backend '%s'\n", psi->name);
+ return -EPERM;
+ }
+
+ /* Sanity check flags. */
+ if (!psi->flags) {
+ pr_warn("backend '%s' must support at least one frontend\n",
+ psi->name);
+ return -EINVAL;
+ }
+
+ /* Check for required functions. */
+ if (!psi->read || !psi->write) {
+ pr_warn("backend '%s' must implement read() and write()\n",
+ psi->name);
+ return -EINVAL;
+ }
+
+ spin_lock(&pstore_lock);
+ if (psinfo) {
+ pr_warn("backend '%s' already loaded: ignoring '%s'\n",
+ psinfo->name, psi->name);
+ spin_unlock(&pstore_lock);
+ return -EBUSY;
+ }
+
+ if (!psi->write_user)
+ psi->write_user = pstore_write_user_compat;
+ psinfo = psi;
+ mutex_init(&psinfo->read_mutex);
+ sema_init(&psinfo->buf_lock, 1);
+ spin_unlock(&pstore_lock);
+
+ if (owner && !try_module_get(owner)) {
+ psinfo = NULL;
+ return -EINVAL;
+ }
+
+ if (psi->flags & PSTORE_FLAGS_DMESG)
+ allocate_buf_for_compression();
+
+ if (pstore_is_mounted())
+ pstore_get_records(0);
+
+ if (psi->flags & PSTORE_FLAGS_DMESG)
+ pstore_register_kmsg();
+ if (psi->flags & PSTORE_FLAGS_CONSOLE)
+ pstore_register_console();
+ if (psi->flags & PSTORE_FLAGS_FTRACE)
+ pstore_register_ftrace();
+ if (psi->flags & PSTORE_FLAGS_PMSG)
+ pstore_register_pmsg();
+
+ /* Start watching for new records, if desired. */
+ if (pstore_update_ms >= 0) {
+ pstore_timer.expires = jiffies +
+ msecs_to_jiffies(pstore_update_ms);
+ add_timer(&pstore_timer);
+ }
+
+ /*
+ * Update the module parameter backend, so it is visible
+ * through /sys/module/pstore/parameters/backend
+ */
+ backend = psi->name;
+
+ pr_info("Registered %s as persistent store backend\n", psi->name);
+
+ module_put(owner);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pstore_register);
+
+void pstore_unregister(struct pstore_info *psi)
+{
+ /* Stop timer and make sure all work has finished. */
+ pstore_update_ms = -1;
+ del_timer_sync(&pstore_timer);
+ flush_work(&pstore_work);
+
+ if (psi->flags & PSTORE_FLAGS_PMSG)
+ pstore_unregister_pmsg();
+ if (psi->flags & PSTORE_FLAGS_FTRACE)
+ pstore_unregister_ftrace();
+ if (psi->flags & PSTORE_FLAGS_CONSOLE)
+ pstore_unregister_console();
+ if (psi->flags & PSTORE_FLAGS_DMESG)
+ pstore_unregister_kmsg();
+
+ free_buf_for_compression();
+
+ psinfo = NULL;
+ backend = NULL;
+}
+EXPORT_SYMBOL_GPL(pstore_unregister);
+
+static void decompress_record(struct pstore_record *record)
+{
+ int unzipped_len;
+ char *decompressed;
+
+ if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !record->compressed)
+ return;
+
+ /* Only PSTORE_TYPE_DMESG support compression. */
+ if (record->type != PSTORE_TYPE_DMESG) {
+ pr_warn("ignored compressed record type %d\n", record->type);
+ return;
+ }
+
+ /* No compression method has created the common buffer. */
+ if (!big_oops_buf) {
+ pr_warn("no decompression buffer allocated\n");
+ return;
+ }
+
+ unzipped_len = pstore_decompress(record->buf, big_oops_buf,
+ record->size, big_oops_buf_sz);
+ if (unzipped_len <= 0) {
+ pr_err("decompression failed: %d\n", unzipped_len);
+ return;
+ }
+
+ /* Build new buffer for decompressed contents. */
+ decompressed = kmalloc(unzipped_len + record->ecc_notice_size,
+ GFP_KERNEL);
+ if (!decompressed) {
+ pr_err("decompression ran out of memory\n");
+ return;
+ }
+ memcpy(decompressed, big_oops_buf, unzipped_len);
+
+ /* Append ECC notice to decompressed buffer. */
+ memcpy(decompressed + unzipped_len, record->buf + record->size,
+ record->ecc_notice_size);
+
+ /* Swap out compresed contents with decompressed contents. */
+ kfree(record->buf);
+ record->buf = decompressed;
+ record->size = unzipped_len;
+ record->compressed = false;
+}
+
+/*
+ * Read all the records from one persistent store backend. 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_backend_records(struct pstore_info *psi,
+ struct dentry *root, int quiet)
+{
+ int failed = 0;
+ unsigned int stop_loop = 65536;
+
+ if (!psi || !root)
+ return;
+
+ mutex_lock(&psi->read_mutex);
+ if (psi->open && psi->open(psi))
+ goto out;
+
+ /*
+ * Backend callback read() allocates record.buf. decompress_record()
+ * may reallocate record.buf. On success, pstore_mkfile() will keep
+ * the record.buf, so free it only on failure.
+ */
+ for (; stop_loop; stop_loop--) {
+ struct pstore_record *record;
+ int rc;
+
+ record = kzalloc(sizeof(*record), GFP_KERNEL);
+ if (!record) {
+ pr_err("out of memory creating record\n");
+ break;
+ }
+ pstore_record_init(record, psi);
+
+ record->size = psi->read(record);
+
+ /* No more records left in backend? */
+ if (record->size <= 0) {
+ kfree(record);
+ break;
+ }
+
+ decompress_record(record);
+ rc = pstore_mkfile(root, record);
+ if (rc) {
+ /* pstore_mkfile() did not take record, so free it. */
+ kfree(record->buf);
+ kfree(record);
+ if (rc != -EEXIST || !quiet)
+ failed++;
+ }
+ }
+ if (psi->close)
+ psi->close(psi);
+out:
+ mutex_unlock(&psi->read_mutex);
+
+ if (failed)
+ pr_warn("failed to create %d record(s) from '%s'\n",
+ failed, psi->name);
+ if (!stop_loop)
+ pr_err("looping? Too many records seen from '%s'\n",
+ psi->name);
+}
+
+static void pstore_dowork(struct work_struct *work)
+{
+ pstore_get_records(1);
+}
+
+static void pstore_timefunc(struct timer_list *unused)
+{
+ if (pstore_new_entry) {
+ pstore_new_entry = 0;
+ schedule_work(&pstore_work);
+ }
+
+ if (pstore_update_ms >= 0)
+ mod_timer(&pstore_timer,
+ jiffies + msecs_to_jiffies(pstore_update_ms));
+}
+
+void __init pstore_choose_compression(void)
+{
+ const struct pstore_zbackend *step;
+
+ if (!compress)
+ return;
+
+ for (step = zbackends; step->name; step++) {
+ if (!strcmp(compress, step->name)) {
+ zbackend = step;
+ return;
+ }
+ }
+}
+
+static int __init pstore_init(void)
+{
+ int ret;
+
+ pstore_choose_compression();
+
+ /*
+ * Check if any pstore backends registered earlier but did not
+ * initialize compression because crypto was not ready. If so,
+ * initialize compression now.
+ */
+ allocate_buf_for_compression();
+
+ ret = pstore_init_fs();
+ if (ret)
+ free_buf_for_compression();
+
+ return ret;
+}
+late_initcall(pstore_init);
+
+static void __exit pstore_exit(void)
+{
+ pstore_exit_fs();
+}
+module_exit(pstore_exit)
+
+module_param(compress, charp, 0444);
+MODULE_PARM_DESC(compress, "Pstore compression to use");
+
+module_param(backend, charp, 0444);
+MODULE_PARM_DESC(backend, "Pstore backend to use");
+
+MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-19 21:47:06 +0000