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847 lines
19 KiB
847 lines
19 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Persistent Storage - platform driver interface parts. |
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* |
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* Copyright (C) 2007-2008 Google, Inc. |
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* Copyright (C) 2010 Intel Corporation <[email protected]> |
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*/ |
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|
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#define pr_fmt(fmt) "pstore: " fmt |
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|
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#include <linux/atomic.h> |
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#include <linux/types.h> |
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#include <linux/errno.h> |
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#include <linux/init.h> |
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#include <linux/kmsg_dump.h> |
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#include <linux/console.h> |
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#include <linux/module.h> |
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#include <linux/pstore.h> |
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS) |
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#include <linux/lzo.h> |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS) |
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#include <linux/lz4.h> |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS) |
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#include <linux/zstd.h> |
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#endif |
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#include <linux/crypto.h> |
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#include <linux/string.h> |
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#include <linux/timer.h> |
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#include <linux/slab.h> |
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#include <linux/uaccess.h> |
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#include <linux/jiffies.h> |
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#include <linux/workqueue.h> |
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#include "internal.h" |
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/* |
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* We defer making "oops" entries appear in pstore - see |
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* whether the system is actually still running well enough |
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* to let someone see the entry |
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*/ |
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static int pstore_update_ms = -1; |
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module_param_named(update_ms, pstore_update_ms, int, 0600); |
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MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content " |
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"(default is -1, which means runtime updates are disabled; " |
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"enabling this option may not be safe; it may lead to further " |
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"corruption on Oopses)"); |
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/* Names should be in the same order as the enum pstore_type_id */ |
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static const char * const pstore_type_names[] = { |
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"dmesg", |
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"mce", |
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"console", |
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"ftrace", |
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"rtas", |
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"powerpc-ofw", |
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"powerpc-common", |
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"pmsg", |
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"powerpc-opal", |
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}; |
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static int pstore_new_entry; |
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static void pstore_timefunc(struct timer_list *); |
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static DEFINE_TIMER(pstore_timer, pstore_timefunc); |
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static void pstore_dowork(struct work_struct *); |
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static DECLARE_WORK(pstore_work, pstore_dowork); |
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/* |
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* psinfo_lock protects "psinfo" during calls to |
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* pstore_register(), pstore_unregister(), and |
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* the filesystem mount/unmount routines. |
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*/ |
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static DEFINE_MUTEX(psinfo_lock); |
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struct pstore_info *psinfo; |
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static char *backend; |
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module_param(backend, charp, 0444); |
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MODULE_PARM_DESC(backend, "specific backend to use"); |
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static char *compress = |
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#ifdef CONFIG_PSTORE_COMPRESS_DEFAULT |
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CONFIG_PSTORE_COMPRESS_DEFAULT; |
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#else |
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NULL; |
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#endif |
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module_param(compress, charp, 0444); |
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MODULE_PARM_DESC(compress, "compression to use"); |
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/* Compression parameters */ |
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static struct crypto_comp *tfm; |
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struct pstore_zbackend { |
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int (*zbufsize)(size_t size); |
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const char *name; |
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}; |
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static char *big_oops_buf; |
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static size_t big_oops_buf_sz; |
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/* How much of the console log to snapshot */ |
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unsigned long kmsg_bytes = CONFIG_PSTORE_DEFAULT_KMSG_BYTES; |
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void pstore_set_kmsg_bytes(int bytes) |
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{ |
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kmsg_bytes = bytes; |
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} |
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/* Tag each group of saved records with a sequence number */ |
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static int oopscount; |
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const char *pstore_type_to_name(enum pstore_type_id type) |
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{ |
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BUILD_BUG_ON(ARRAY_SIZE(pstore_type_names) != PSTORE_TYPE_MAX); |
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if (WARN_ON_ONCE(type >= PSTORE_TYPE_MAX)) |
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return "unknown"; |
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return pstore_type_names[type]; |
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} |
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EXPORT_SYMBOL_GPL(pstore_type_to_name); |
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enum pstore_type_id pstore_name_to_type(const char *name) |
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{ |
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int i; |
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for (i = 0; i < PSTORE_TYPE_MAX; i++) { |
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if (!strcmp(pstore_type_names[i], name)) |
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return i; |
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} |
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return PSTORE_TYPE_MAX; |
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} |
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EXPORT_SYMBOL_GPL(pstore_name_to_type); |
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static void pstore_timer_kick(void) |
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{ |
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if (pstore_update_ms < 0) |
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return; |
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mod_timer(&pstore_timer, jiffies + msecs_to_jiffies(pstore_update_ms)); |
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} |
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/* |
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* Should pstore_dump() wait for a concurrent pstore_dump()? If |
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* not, the current pstore_dump() will report a failure to dump |
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* and return. |
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*/ |
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static bool pstore_cannot_wait(enum kmsg_dump_reason reason) |
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{ |
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/* In NMI path, pstore shouldn't block regardless of reason. */ |
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if (in_nmi()) |
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return true; |
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switch (reason) { |
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/* In panic case, other cpus are stopped by smp_send_stop(). */ |
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case KMSG_DUMP_PANIC: |
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/* Emergency restart shouldn't be blocked. */ |
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case KMSG_DUMP_EMERG: |
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return true; |
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default: |
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return false; |
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} |
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} |
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#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS) |
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static int zbufsize_deflate(size_t size) |
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{ |
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size_t cmpr; |
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|
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switch (size) { |
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/* buffer range for efivars */ |
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case 1000 ... 2000: |
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cmpr = 56; |
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break; |
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case 2001 ... 3000: |
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cmpr = 54; |
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break; |
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case 3001 ... 3999: |
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cmpr = 52; |
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break; |
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/* buffer range for nvram, erst */ |
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case 4000 ... 10000: |
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cmpr = 45; |
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break; |
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default: |
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cmpr = 60; |
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break; |
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} |
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return (size * 100) / cmpr; |
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} |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS) |
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static int zbufsize_lzo(size_t size) |
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{ |
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return lzo1x_worst_compress(size); |
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} |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS) |
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static int zbufsize_lz4(size_t size) |
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{ |
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return LZ4_compressBound(size); |
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} |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS) |
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static int zbufsize_842(size_t size) |
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{ |
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return size; |
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} |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS) |
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static int zbufsize_zstd(size_t size) |
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{ |
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return ZSTD_compressBound(size); |
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} |
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#endif |
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static const struct pstore_zbackend *zbackend __ro_after_init; |
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static const struct pstore_zbackend zbackends[] = { |
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#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS) |
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{ |
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.zbufsize = zbufsize_deflate, |
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.name = "deflate", |
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}, |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS) |
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{ |
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.zbufsize = zbufsize_lzo, |
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.name = "lzo", |
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}, |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) |
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{ |
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.zbufsize = zbufsize_lz4, |
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.name = "lz4", |
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}, |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS) |
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{ |
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.zbufsize = zbufsize_lz4, |
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.name = "lz4hc", |
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}, |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS) |
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{ |
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.zbufsize = zbufsize_842, |
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.name = "842", |
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}, |
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#endif |
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS) |
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{ |
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.zbufsize = zbufsize_zstd, |
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.name = "zstd", |
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}, |
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#endif |
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{ } |
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}; |
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static int pstore_compress(const void *in, void *out, |
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unsigned int inlen, unsigned int outlen) |
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{ |
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int ret; |
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if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS)) |
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return -EINVAL; |
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ret = crypto_comp_compress(tfm, in, inlen, out, &outlen); |
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if (ret) { |
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pr_err("crypto_comp_compress failed, ret = %d!\n", ret); |
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return ret; |
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} |
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return outlen; |
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} |
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static void allocate_buf_for_compression(void) |
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{ |
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struct crypto_comp *ctx; |
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int size; |
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char *buf; |
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|
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/* Skip if not built-in or compression backend not selected yet. */ |
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if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend) |
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return; |
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/* Skip if no pstore backend yet or compression init already done. */ |
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if (!psinfo || tfm) |
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return; |
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if (!crypto_has_comp(zbackend->name, 0, 0)) { |
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pr_err("Unknown compression: %s\n", zbackend->name); |
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return; |
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} |
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size = zbackend->zbufsize(psinfo->bufsize); |
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if (size <= 0) { |
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pr_err("Invalid compression size for %s: %d\n", |
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zbackend->name, size); |
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return; |
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} |
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buf = kmalloc(size, GFP_KERNEL); |
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if (!buf) { |
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pr_err("Failed %d byte compression buffer allocation for: %s\n", |
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size, zbackend->name); |
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return; |
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} |
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ctx = crypto_alloc_comp(zbackend->name, 0, 0); |
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if (IS_ERR_OR_NULL(ctx)) { |
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kfree(buf); |
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pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name, |
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PTR_ERR(ctx)); |
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return; |
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} |
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/* A non-NULL big_oops_buf indicates compression is available. */ |
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tfm = ctx; |
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big_oops_buf_sz = size; |
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big_oops_buf = buf; |
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pr_info("Using crash dump compression: %s\n", zbackend->name); |
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} |
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static void free_buf_for_compression(void) |
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{ |
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if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && tfm) { |
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crypto_free_comp(tfm); |
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tfm = NULL; |
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} |
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kfree(big_oops_buf); |
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big_oops_buf = NULL; |
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big_oops_buf_sz = 0; |
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} |
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/* |
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* Called when compression fails, since the printk buffer |
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* would be fetched for compression calling it again when |
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* compression fails would have moved the iterator of |
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* printk buffer which results in fetching old contents. |
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* Copy the recent messages from big_oops_buf to psinfo->buf |
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*/ |
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static size_t copy_kmsg_to_buffer(int hsize, size_t len) |
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{ |
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size_t total_len; |
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size_t diff; |
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total_len = hsize + len; |
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if (total_len > psinfo->bufsize) { |
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diff = total_len - psinfo->bufsize + hsize; |
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memcpy(psinfo->buf, big_oops_buf, hsize); |
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memcpy(psinfo->buf + hsize, big_oops_buf + diff, |
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psinfo->bufsize - hsize); |
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total_len = psinfo->bufsize; |
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} else |
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memcpy(psinfo->buf, big_oops_buf, total_len); |
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return total_len; |
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} |
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void pstore_record_init(struct pstore_record *record, |
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struct pstore_info *psinfo) |
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{ |
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memset(record, 0, sizeof(*record)); |
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record->psi = psinfo; |
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|
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/* Report zeroed timestamp if called before timekeeping has resumed. */ |
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record->time = ns_to_timespec64(ktime_get_real_fast_ns()); |
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} |
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/* |
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* callback from kmsg_dump. Save as much as we can (up to kmsg_bytes) from the |
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* end of the buffer. |
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*/ |
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static void pstore_dump(struct kmsg_dumper *dumper, |
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enum kmsg_dump_reason reason) |
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{ |
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unsigned long total = 0; |
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const char *why; |
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unsigned int part = 1; |
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int ret; |
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why = kmsg_dump_reason_str(reason); |
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if (down_trylock(&psinfo->buf_lock)) { |
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/* Failed to acquire lock: give up if we cannot wait. */ |
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if (pstore_cannot_wait(reason)) { |
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pr_err("dump skipped in %s path: may corrupt error record\n", |
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in_nmi() ? "NMI" : why); |
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return; |
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} |
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if (down_interruptible(&psinfo->buf_lock)) { |
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pr_err("could not grab semaphore?!\n"); |
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return; |
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} |
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} |
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oopscount++; |
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while (total < kmsg_bytes) { |
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char *dst; |
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size_t dst_size; |
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int header_size; |
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int zipped_len = -1; |
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size_t dump_size; |
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struct pstore_record record; |
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pstore_record_init(&record, psinfo); |
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record.type = PSTORE_TYPE_DMESG; |
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record.count = oopscount; |
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record.reason = reason; |
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record.part = part; |
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record.buf = psinfo->buf; |
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if (big_oops_buf) { |
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dst = big_oops_buf; |
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dst_size = big_oops_buf_sz; |
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} else { |
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dst = psinfo->buf; |
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dst_size = psinfo->bufsize; |
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} |
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/* Write dump header. */ |
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header_size = snprintf(dst, dst_size, "%s#%d Part%u\n", why, |
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oopscount, part); |
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dst_size -= header_size; |
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/* Write dump contents. */ |
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if (!kmsg_dump_get_buffer(dumper, true, dst + header_size, |
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dst_size, &dump_size)) |
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break; |
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if (big_oops_buf) { |
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zipped_len = pstore_compress(dst, psinfo->buf, |
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header_size + dump_size, |
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psinfo->bufsize); |
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if (zipped_len > 0) { |
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record.compressed = true; |
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record.size = zipped_len; |
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} else { |
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record.size = copy_kmsg_to_buffer(header_size, |
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dump_size); |
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} |
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} else { |
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record.size = header_size + dump_size; |
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} |
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ret = psinfo->write(&record); |
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if (ret == 0 && reason == KMSG_DUMP_OOPS) { |
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pstore_new_entry = 1; |
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pstore_timer_kick(); |
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} |
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total += record.size; |
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part++; |
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} |
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up(&psinfo->buf_lock); |
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} |
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static struct kmsg_dumper pstore_dumper = { |
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.dump = pstore_dump, |
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}; |
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/* |
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* Register with kmsg_dump to save last part of console log on panic. |
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*/ |
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static void pstore_register_kmsg(void) |
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{ |
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kmsg_dump_register(&pstore_dumper); |
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} |
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static void pstore_unregister_kmsg(void) |
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{ |
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kmsg_dump_unregister(&pstore_dumper); |
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} |
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#ifdef CONFIG_PSTORE_CONSOLE |
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static void pstore_console_write(struct console *con, const char *s, unsigned c) |
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{ |
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struct pstore_record record; |
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if (!c) |
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return; |
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pstore_record_init(&record, psinfo); |
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record.type = PSTORE_TYPE_CONSOLE; |
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record.buf = (char *)s; |
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record.size = c; |
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psinfo->write(&record); |
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} |
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static struct console pstore_console = { |
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.write = pstore_console_write, |
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.index = -1, |
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}; |
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static void pstore_register_console(void) |
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{ |
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/* Show which backend is going to get console writes. */ |
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strscpy(pstore_console.name, psinfo->name, |
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sizeof(pstore_console.name)); |
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/* |
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* Always initialize flags here since prior unregister_console() |
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* calls may have changed settings (specifically CON_ENABLED). |
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*/ |
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pstore_console.flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME; |
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register_console(&pstore_console); |
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} |
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static void pstore_unregister_console(void) |
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{ |
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unregister_console(&pstore_console); |
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} |
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#else |
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static void pstore_register_console(void) {} |
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static void pstore_unregister_console(void) {} |
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#endif |
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static int pstore_write_user_compat(struct pstore_record *record, |
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const char __user *buf) |
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{ |
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int ret = 0; |
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|
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if (record->buf) |
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return -EINVAL; |
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record->buf = memdup_user(buf, record->size); |
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if (IS_ERR(record->buf)) { |
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ret = PTR_ERR(record->buf); |
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goto out; |
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} |
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ret = record->psi->write(record); |
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|
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kfree(record->buf); |
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out: |
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record->buf = NULL; |
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return unlikely(ret < 0) ? ret : record->size; |
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} |
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|
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/* |
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* platform specific persistent storage driver registers with |
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* us here. If pstore is already mounted, call the platform |
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* read function right away to populate the file system. If not |
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* then the pstore mount code will call us later to fill out |
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* the file system. |
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*/ |
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int pstore_register(struct pstore_info *psi) |
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{ |
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if (backend && strcmp(backend, psi->name)) { |
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pr_warn("ignoring unexpected backend '%s'\n", psi->name); |
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return -EPERM; |
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} |
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|
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/* Sanity check flags. */ |
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if (!psi->flags) { |
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pr_warn("backend '%s' must support at least one frontend\n", |
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psi->name); |
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return -EINVAL; |
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} |
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|
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/* Check for required functions. */ |
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if (!psi->read || !psi->write) { |
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pr_warn("backend '%s' must implement read() and write()\n", |
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psi->name); |
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return -EINVAL; |
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} |
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mutex_lock(&psinfo_lock); |
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if (psinfo) { |
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pr_warn("backend '%s' already loaded: ignoring '%s'\n", |
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psinfo->name, psi->name); |
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mutex_unlock(&psinfo_lock); |
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return -EBUSY; |
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} |
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|
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if (!psi->write_user) |
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psi->write_user = pstore_write_user_compat; |
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psinfo = psi; |
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mutex_init(&psinfo->read_mutex); |
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sema_init(&psinfo->buf_lock, 1); |
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|
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if (psi->flags & PSTORE_FLAGS_DMESG) |
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allocate_buf_for_compression(); |
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|
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pstore_get_records(0); |
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|
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if (psi->flags & PSTORE_FLAGS_DMESG) { |
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pstore_dumper.max_reason = psinfo->max_reason; |
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pstore_register_kmsg(); |
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} |
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if (psi->flags & PSTORE_FLAGS_CONSOLE) |
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pstore_register_console(); |
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if (psi->flags & PSTORE_FLAGS_FTRACE) |
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pstore_register_ftrace(); |
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if (psi->flags & PSTORE_FLAGS_PMSG) |
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pstore_register_pmsg(); |
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|
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/* Start watching for new records, if desired. */ |
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pstore_timer_kick(); |
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|
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/* |
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* Update the module parameter backend, so it is visible |
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* through /sys/module/pstore/parameters/backend |
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*/ |
|
backend = kstrdup(psi->name, GFP_KERNEL); |
|
|
|
pr_info("Registered %s as persistent store backend\n", psi->name); |
|
|
|
mutex_unlock(&psinfo_lock); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(pstore_register); |
|
|
|
void pstore_unregister(struct pstore_info *psi) |
|
{ |
|
/* It's okay to unregister nothing. */ |
|
if (!psi) |
|
return; |
|
|
|
mutex_lock(&psinfo_lock); |
|
|
|
/* Only one backend can be registered at a time. */ |
|
if (WARN_ON(psi != psinfo)) { |
|
mutex_unlock(&psinfo_lock); |
|
return; |
|
} |
|
|
|
/* Unregister all callbacks. */ |
|
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(); |
|
|
|
/* Stop timer and make sure all work has finished. */ |
|
del_timer_sync(&pstore_timer); |
|
flush_work(&pstore_work); |
|
|
|
/* Remove all backend records from filesystem tree. */ |
|
pstore_put_backend_records(psi); |
|
|
|
free_buf_for_compression(); |
|
|
|
psinfo = NULL; |
|
kfree(backend); |
|
backend = NULL; |
|
mutex_unlock(&psinfo_lock); |
|
} |
|
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); |
|
} |
|
|
|
pstore_timer_kick(); |
|
} |
|
|
|
static 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_AUTHOR("Tony Luck <[email protected]>"); |
|
MODULE_LICENSE("GPL");
|
|
|