| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Persistent Storage - platform driver interface parts. |
| * |
| * Copyright (C) 2007-2008 Google, Inc. |
| * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com> |
| */ |
| |
| #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)"); |
| |
| /* Names should be in the same order as the enum pstore_type_id */ |
| static const char * const pstore_type_names[] = { |
| "dmesg", |
| "mce", |
| "console", |
| "ftrace", |
| "rtas", |
| "powerpc-ofw", |
| "powerpc-common", |
| "pmsg", |
| "powerpc-opal", |
| }; |
| |
| 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; |
| |
| const char *pstore_type_to_name(enum pstore_type_id type) |
| { |
| BUILD_BUG_ON(ARRAY_SIZE(pstore_type_names) != PSTORE_TYPE_MAX); |
| |
| if (WARN_ON_ONCE(type >= PSTORE_TYPE_MAX)) |
| return "unknown"; |
| |
| return pstore_type_names[type]; |
| } |
| EXPORT_SYMBOL_GPL(pstore_type_to_name); |
| |
| enum pstore_type_id pstore_name_to_type(const char *name) |
| { |
| int i; |
| |
| for (i = 0; i < PSTORE_TYPE_MAX; i++) { |
| if (!strcmp(pstore_type_names[i], name)) |
| return i; |
| } |
| |
| return PSTORE_TYPE_MAX; |
| } |
| EXPORT_SYMBOL_GPL(pstore_name_to_type); |
| |
| 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 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 crash dump 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. Save as much as we can (up to kmsg_bytes) 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; |
| |
| if (!c) |
| return; |
| |
| 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 ret; |
| int unzipped_len; |
| char *unzipped, *workspace; |
| |
| 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; |
| } |
| |
| /* Missing compression buffer means compression was not initialized. */ |
| if (!big_oops_buf) { |
| pr_warn("no decompression method initialized!\n"); |
| return; |
| } |
| |
| /* Allocate enough space to hold max decompression and ECC. */ |
| unzipped_len = big_oops_buf_sz; |
| workspace = kmalloc(unzipped_len + record->ecc_notice_size, |
| GFP_KERNEL); |
| if (!workspace) |
| return; |
| |
| /* After decompression "unzipped_len" is almost certainly smaller. */ |
| ret = crypto_comp_decompress(tfm, record->buf, record->size, |
| workspace, &unzipped_len); |
| if (ret) { |
| pr_err("crypto_comp_decompress failed, ret = %d!\n", ret); |
| kfree(workspace); |
| return; |
| } |
| |
| /* Append ECC notice to decompressed buffer. */ |
| memcpy(workspace + unzipped_len, record->buf + record->size, |
| record->ecc_notice_size); |
| |
| /* Copy decompressed contents into an minimum-sized allocation. */ |
| unzipped = kmemdup(workspace, unzipped_len + record->ecc_notice_size, |
| GFP_KERNEL); |
| kfree(workspace); |
| if (!unzipped) |
| return; |
| |
| /* Swap out compressed contents with decompressed contents. */ |
| kfree(record->buf); |
| record->buf = unzipped; |
| 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"); |