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-rw-r--r--kernel/power/hibernate.c107
1 files changed, 105 insertions, 2 deletions
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 4b0b7cf2e019..43b1a82e800c 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -47,6 +47,15 @@ dev_t swsusp_resume_device;
sector_t swsusp_resume_block;
__visible int in_suspend __nosavedata;
+static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
+
+/*
+ * Compression/decompression algorithm to be used while saving/loading
+ * image to/from disk. This would later be used in 'kernel/power/swap.c'
+ * to allocate comp streams.
+ */
+char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
+
enum {
HIBERNATION_INVALID,
HIBERNATION_PLATFORM,
@@ -718,6 +727,9 @@ static int load_image_and_restore(void)
return error;
}
+#define COMPRESSION_ALGO_LZO "lzo"
+#define COMPRESSION_ALGO_LZ4 "lz4"
+
/**
* hibernate - Carry out system hibernation, including saving the image.
*/
@@ -732,6 +744,17 @@ int hibernate(void)
return -EPERM;
}
+ /*
+ * Query for the compression algorithm support if compression is enabled.
+ */
+ if (!nocompress) {
+ strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo));
+ if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
+ pr_err("%s compression is not available\n", hib_comp_algo);
+ return -EOPNOTSUPP;
+ }
+ }
+
sleep_flags = lock_system_sleep();
/* The snapshot device should not be opened while we're running */
if (!hibernate_acquire()) {
@@ -766,11 +789,24 @@ int hibernate(void)
if (hibernation_mode == HIBERNATION_PLATFORM)
flags |= SF_PLATFORM_MODE;
- if (nocompress)
+ if (nocompress) {
flags |= SF_NOCOMPRESS_MODE;
- else
+ } else {
flags |= SF_CRC32_MODE;
+ /*
+ * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
+ * to override this behaviour and use LZ4.
+ *
+ * Refer kernel/power/power.h for more details
+ */
+
+ if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
+ flags |= SF_COMPRESSION_ALG_LZ4;
+ else
+ flags |= SF_COMPRESSION_ALG_LZO;
+ }
+
pm_pr_dbg("Writing hibernation image.\n");
error = swsusp_write(flags);
swsusp_free();
@@ -955,6 +991,22 @@ static int software_resume(void)
if (error)
goto Unlock;
+ /*
+ * Check if the hibernation image is compressed. If so, query for
+ * the algorithm support.
+ */
+ if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
+ if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
+ strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo));
+ else
+ strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo));
+ if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
+ pr_err("%s compression is not available\n", hib_comp_algo);
+ error = -EOPNOTSUPP;
+ goto Unlock;
+ }
+ }
+
/* The snapshot device should not be opened while we're running */
if (!hibernate_acquire()) {
error = -EBUSY;
@@ -1370,6 +1422,57 @@ static int __init nohibernate_setup(char *str)
return 1;
}
+static const char * const comp_alg_enabled[] = {
+#if IS_ENABLED(CONFIG_CRYPTO_LZO)
+ COMPRESSION_ALGO_LZO,
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
+ COMPRESSION_ALGO_LZ4,
+#endif
+};
+
+static int hibernate_compressor_param_set(const char *compressor,
+ const struct kernel_param *kp)
+{
+ unsigned int sleep_flags;
+ int index, ret;
+
+ sleep_flags = lock_system_sleep();
+
+ index = sysfs_match_string(comp_alg_enabled, compressor);
+ if (index >= 0) {
+ ret = param_set_copystring(comp_alg_enabled[index], kp);
+ if (!ret)
+ strscpy(hib_comp_algo, comp_alg_enabled[index],
+ sizeof(hib_comp_algo));
+ } else {
+ ret = index;
+ }
+
+ unlock_system_sleep(sleep_flags);
+
+ if (ret)
+ pr_debug("Cannot set specified compressor %s\n",
+ compressor);
+
+ return ret;
+}
+
+static const struct kernel_param_ops hibernate_compressor_param_ops = {
+ .set = hibernate_compressor_param_set,
+ .get = param_get_string,
+};
+
+static struct kparam_string hibernate_compressor_param_string = {
+ .maxlen = sizeof(hibernate_compressor),
+ .string = hibernate_compressor,
+};
+
+module_param_cb(compressor, &hibernate_compressor_param_ops,
+ &hibernate_compressor_param_string, 0644);
+MODULE_PARM_DESC(compressor,
+ "Compression algorithm to be used with hibernation");
+
__setup("noresume", noresume_setup);
__setup("resume_offset=", resume_offset_setup);
__setup("resume=", resume_setup);