Merge tag 'pstore-v4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore updates from Kees Cook:
"Improvements and refactorings:
- Improve compression handling
- Refactor argument handling during initialization
- Avoid needless locking for saner EFI backend handling
- Add more kern-doc and improve debugging output"
* tag 'pstore-v4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Avoid NULL deref in ftrace merging failure path
pstore: Convert buf_lock to semaphore
pstore: Fix bool initialization/comparison
pstore/ram: Do not treat empty buffers as valid
pstore/ram: Simplify ramoops_get_next_prz() arguments
pstore: Map PSTORE_TYPE_* to strings
pstore: Replace open-coded << with BIT()
pstore: Improve and update some comments and status output
pstore/ram: Add kern-doc for struct persistent_ram_zone
pstore/ram: Report backend assignments with finer granularity
pstore/ram: Standardize module name in ramoops
pstore: Avoid duplicate call of persistent_ram_zap()
pstore: Remove needless lock during console writes
pstore: Do not use crash buffer for decompression
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 06e2eda..38b03a3 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -563,8 +563,6 @@ static int nvram_pstore_init(void)
nvram_pstore_info.buf = oops_data;
nvram_pstore_info.bufsize = oops_data_sz;
- spin_lock_init(&nvram_pstore_info.buf_lock);
-
rc = pstore_register(&nvram_pstore_info);
if (rc && (rc != -EPERM))
/* Print error only when pstore.backend == nvram */
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index 3c5ea7c..9953e50 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -1035,7 +1035,7 @@ static ssize_t erst_reader(struct pstore_record *record)
CPER_SECTION_TYPE_MCE) == 0)
record->type = PSTORE_TYPE_MCE;
else
- record->type = PSTORE_TYPE_UNKNOWN;
+ record->type = PSTORE_TYPE_MAX;
if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP)
record->time.tv_sec = rcd->hdr.timestamp;
@@ -1176,7 +1176,6 @@ static int __init erst_init(void)
"Error Record Serialization Table (ERST) support is initialized.\n");
buf = kmalloc(erst_erange.size, GFP_KERNEL);
- spin_lock_init(&erst_info.buf_lock);
if (buf) {
erst_info.buf = buf + sizeof(struct cper_pstore_record);
erst_info.bufsize = erst_erange.size -
diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index cfe87b4..0f7d979 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -259,8 +259,7 @@ static int efi_pstore_write(struct pstore_record *record)
efi_name[i] = name[i];
ret = efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES,
- !pstore_cannot_block_path(record->reason),
- record->size, record->psi->buf);
+ preemptible(), record->size, record->psi->buf);
if (record->reason == KMSG_DUMP_OOPS)
efivar_run_worker();
@@ -369,7 +368,6 @@ static __init int efivars_pstore_init(void)
return -ENOMEM;
efi_pstore_info.bufsize = 1024;
- spin_lock_init(&efi_pstore_info.buf_lock);
if (pstore_register(&efi_pstore_info)) {
kfree(efi_pstore_info.buf);
diff --git a/fs/pstore/ftrace.c b/fs/pstore/ftrace.c
index 06aab07..b8a0931 100644
--- a/fs/pstore/ftrace.c
+++ b/fs/pstore/ftrace.c
@@ -148,7 +148,7 @@ void pstore_unregister_ftrace(void)
mutex_lock(&pstore_ftrace_lock);
if (pstore_ftrace_enabled) {
unregister_ftrace_function(&pstore_ftrace_ops);
- pstore_ftrace_enabled = 0;
+ pstore_ftrace_enabled = false;
}
mutex_unlock(&pstore_ftrace_lock);
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 8cf2218..c60ee46 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -335,53 +335,10 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)
goto fail_alloc;
private->record = record;
- switch (record->type) {
- case PSTORE_TYPE_DMESG:
- scnprintf(name, sizeof(name), "dmesg-%s-%llu%s",
- record->psi->name, record->id,
- record->compressed ? ".enc.z" : "");
- break;
- case PSTORE_TYPE_CONSOLE:
- scnprintf(name, sizeof(name), "console-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_FTRACE:
- scnprintf(name, sizeof(name), "ftrace-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_MCE:
- scnprintf(name, sizeof(name), "mce-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_PPC_RTAS:
- scnprintf(name, sizeof(name), "rtas-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_PPC_OF:
- scnprintf(name, sizeof(name), "powerpc-ofw-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_PPC_COMMON:
- scnprintf(name, sizeof(name), "powerpc-common-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_PMSG:
- scnprintf(name, sizeof(name), "pmsg-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_PPC_OPAL:
- scnprintf(name, sizeof(name), "powerpc-opal-%s-%llu",
- record->psi->name, record->id);
- break;
- case PSTORE_TYPE_UNKNOWN:
- scnprintf(name, sizeof(name), "unknown-%s-%llu",
- record->psi->name, record->id);
- break;
- default:
- scnprintf(name, sizeof(name), "type%d-%s-%llu",
- record->type, record->psi->name, record->id);
- break;
- }
+ scnprintf(name, sizeof(name), "%s-%s-%llu%s",
+ pstore_type_to_name(record->type),
+ record->psi->name, record->id,
+ record->compressed ? ".enc.z" : "");
dentry = d_alloc_name(root, name);
if (!dentry)
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index b821054..2d1066e 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -59,6 +59,19 @@ MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content "
"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 *);
@@ -104,6 +117,30 @@ void pstore_set_kmsg_bytes(int 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) {
@@ -124,26 +161,27 @@ static const char *get_reason_str(enum kmsg_dump_reason reason)
}
}
-bool pstore_cannot_block_path(enum kmsg_dump_reason reason)
+/*
+ * 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 case of NMI path, pstore shouldn't be blocked
- * regardless of 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 by spin lock. */
+ /* Emergency restart shouldn't be blocked. */
case KMSG_DUMP_EMERG:
return true;
default:
return false;
}
}
-EXPORT_SYMBOL_GPL(pstore_cannot_block_path);
#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
static int zbufsize_deflate(size_t size)
@@ -258,20 +296,6 @@ static int pstore_compress(const void *in, void *out,
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;
@@ -318,7 +342,7 @@ static void allocate_buf_for_compression(void)
big_oops_buf_sz = size;
big_oops_buf = buf;
- pr_info("Using compression: %s\n", zbackend->name);
+ pr_info("Using crash dump compression: %s\n", zbackend->name);
}
static void free_buf_for_compression(void)
@@ -368,9 +392,8 @@ void pstore_record_init(struct pstore_record *record,
}
/*
- * 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.
+ * 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)
@@ -378,23 +401,23 @@ static void pstore_dump(struct kmsg_dumper *dumper,
unsigned long total = 0;
const char *why;
unsigned int part = 1;
- unsigned long flags = 0;
- int is_locked;
int ret;
why = get_reason_str(reason);
- if (pstore_cannot_block_path(reason)) {
- is_locked = spin_trylock_irqsave(&psinfo->buf_lock, flags);
- if (!is_locked) {
- pr_err("pstore dump routine blocked in %s path, may corrupt error record\n"
- , in_nmi() ? "NMI" : why);
+ 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;
}
- } else {
- spin_lock_irqsave(&psinfo->buf_lock, flags);
- is_locked = 1;
+ if (down_interruptible(&psinfo->buf_lock)) {
+ pr_err("could not grab semaphore?!\n");
+ return;
+ }
}
+
oopscount++;
while (total < kmsg_bytes) {
char *dst;
@@ -411,7 +434,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
record.part = part;
record.buf = psinfo->buf;
- if (big_oops_buf && is_locked) {
+ if (big_oops_buf) {
dst = big_oops_buf;
dst_size = big_oops_buf_sz;
} else {
@@ -429,7 +452,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
dst_size, &dump_size))
break;
- if (big_oops_buf && is_locked) {
+ if (big_oops_buf) {
zipped_len = pstore_compress(dst, psinfo->buf,
header_size + dump_size,
psinfo->bufsize);
@@ -452,8 +475,8 @@ static void pstore_dump(struct kmsg_dumper *dumper,
total += record.size;
part++;
}
- if (is_locked)
- spin_unlock_irqrestore(&psinfo->buf_lock, flags);
+
+ up(&psinfo->buf_lock);
}
static struct kmsg_dumper pstore_dumper = {
@@ -476,31 +499,14 @@ static void pstore_unregister_kmsg(void)
#ifdef CONFIG_PSTORE_CONSOLE
static void pstore_console_write(struct console *con, const char *s, unsigned c)
{
- const char *e = s + c;
+ struct pstore_record record;
- while (s < e) {
- struct pstore_record record;
- unsigned long flags;
+ pstore_record_init(&record, psinfo);
+ record.type = PSTORE_TYPE_CONSOLE;
- pstore_record_init(&record, psinfo);
- record.type = PSTORE_TYPE_CONSOLE;
-
- if (c > psinfo->bufsize)
- c = psinfo->bufsize;
-
- if (oops_in_progress) {
- if (!spin_trylock_irqsave(&psinfo->buf_lock, flags))
- break;
- } else {
- spin_lock_irqsave(&psinfo->buf_lock, flags);
- }
- record.buf = (char *)s;
- record.size = c;
- psinfo->write(&record);
- spin_unlock_irqrestore(&psinfo->buf_lock, flags);
- s += c;
- c = e - s;
- }
+ record.buf = (char *)s;
+ record.size = c;
+ psinfo->write(&record);
}
static struct console pstore_console = {
@@ -589,6 +595,7 @@ int pstore_register(struct pstore_info *psi)
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)) {
@@ -656,8 +663,9 @@ EXPORT_SYMBOL_GPL(pstore_unregister);
static void decompress_record(struct pstore_record *record)
{
+ int ret;
int unzipped_len;
- char *decompressed;
+ char *unzipped, *workspace;
if (!record->compressed)
return;
@@ -668,35 +676,42 @@ static void decompress_record(struct pstore_record *record)
return;
}
- /* No compression method has created the common buffer. */
+ /* Missing compression buffer means compression was not initialized. */
if (!big_oops_buf) {
- pr_warn("no decompression buffer allocated\n");
+ pr_warn("no decompression method initialized!\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);
+ /* 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;
- }
- /* 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");
+ /* 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;
}
- memcpy(decompressed, big_oops_buf, unzipped_len);
/* Append ECC notice to decompressed buffer. */
- memcpy(decompressed + unzipped_len, record->buf + record->size,
+ memcpy(workspace + unzipped_len, record->buf + record->size,
record->ecc_notice_size);
- /* Swap out compresed contents with decompressed contents. */
+ /* 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 = decompressed;
+ record->buf = unzipped;
record->size = unzipped_len;
record->compressed = false;
}
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index e02a903..96f7d32 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -124,19 +124,17 @@ static int ramoops_pstore_open(struct pstore_info *psi)
}
static struct persistent_ram_zone *
-ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
- u64 *id,
- enum pstore_type_id *typep, enum pstore_type_id type,
- bool update)
+ramoops_get_next_prz(struct persistent_ram_zone *przs[], int id,
+ struct pstore_record *record)
{
struct persistent_ram_zone *prz;
- int i = (*c)++;
+ bool update = (record->type == PSTORE_TYPE_DMESG);
/* Give up if we never existed or have hit the end. */
- if (!przs || i >= max)
+ if (!przs)
return NULL;
- prz = przs[i];
+ prz = przs[id];
if (!prz)
return NULL;
@@ -147,8 +145,8 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
if (!persistent_ram_old_size(prz))
return NULL;
- *typep = type;
- *id = i;
+ record->type = prz->type;
+ record->id = id;
return prz;
}
@@ -255,10 +253,8 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
/* Find the next valid persistent_ram_zone for DMESG */
while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) {
- prz = ramoops_get_next_prz(cxt->dprzs, &cxt->dump_read_cnt,
- cxt->max_dump_cnt, &record->id,
- &record->type,
- PSTORE_TYPE_DMESG, 1);
+ prz = ramoops_get_next_prz(cxt->dprzs, cxt->dump_read_cnt++,
+ record);
if (!prz_ok(prz))
continue;
header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz),
@@ -272,22 +268,18 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
}
}
- if (!prz_ok(prz))
- prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
- 1, &record->id, &record->type,
- PSTORE_TYPE_CONSOLE, 0);
+ if (!prz_ok(prz) && !cxt->console_read_cnt++)
+ prz = ramoops_get_next_prz(&cxt->cprz, 0 /* single */, record);
- if (!prz_ok(prz))
- prz = ramoops_get_next_prz(&cxt->mprz, &cxt->pmsg_read_cnt,
- 1, &record->id, &record->type,
- PSTORE_TYPE_PMSG, 0);
+ if (!prz_ok(prz) && !cxt->pmsg_read_cnt++)
+ prz = ramoops_get_next_prz(&cxt->mprz, 0 /* single */, record);
/* ftrace is last since it may want to dynamically allocate memory. */
if (!prz_ok(prz)) {
- if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)) {
- prz = ramoops_get_next_prz(cxt->fprzs,
- &cxt->ftrace_read_cnt, 1, &record->id,
- &record->type, PSTORE_TYPE_FTRACE, 0);
+ if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) &&
+ !cxt->ftrace_read_cnt++) {
+ prz = ramoops_get_next_prz(cxt->fprzs, 0 /* single */,
+ record);
} else {
/*
* Build a new dummy record which combines all the
@@ -299,15 +291,12 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
GFP_KERNEL);
if (!tmp_prz)
return -ENOMEM;
+ prz = tmp_prz;
free_prz = true;
while (cxt->ftrace_read_cnt < cxt->max_ftrace_cnt) {
prz_next = ramoops_get_next_prz(cxt->fprzs,
- &cxt->ftrace_read_cnt,
- cxt->max_ftrace_cnt,
- &record->id,
- &record->type,
- PSTORE_TYPE_FTRACE, 0);
+ cxt->ftrace_read_cnt++, record);
if (!prz_ok(prz_next))
continue;
@@ -321,7 +310,6 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
goto out;
}
record->id = 0;
- prz = tmp_prz;
}
}
@@ -611,6 +599,7 @@ static int ramoops_init_przs(const char *name,
goto fail;
}
*paddr += zone_sz;
+ prz_ar[i]->type = pstore_name_to_type(name);
}
*przs = prz_ar;
@@ -640,7 +629,7 @@ static int ramoops_init_prz(const char *name,
label = kasprintf(GFP_KERNEL, "ramoops:%s", name);
*prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info,
- cxt->memtype, 0, label);
+ cxt->memtype, PRZ_FLAG_ZAP_OLD, label);
if (IS_ERR(*prz)) {
int err = PTR_ERR(*prz);
@@ -649,9 +638,8 @@ static int ramoops_init_prz(const char *name,
return err;
}
- persistent_ram_zap(*prz);
-
*paddr += sz;
+ (*prz)->type = pstore_name_to_type(name);
return 0;
}
@@ -787,7 +775,7 @@ static int ramoops_probe(struct platform_device *pdev)
dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size
- cxt->pmsg_size;
- err = ramoops_init_przs("dump", dev, cxt, &cxt->dprzs, &paddr,
+ err = ramoops_init_przs("dmesg", dev, cxt, &cxt->dprzs, &paddr,
dump_mem_sz, cxt->record_size,
&cxt->max_dump_cnt, 0, 0);
if (err)
@@ -827,7 +815,6 @@ static int ramoops_probe(struct platform_device *pdev)
err = -ENOMEM;
goto fail_clear;
}
- spin_lock_init(&cxt->pstore.buf_lock);
cxt->pstore.flags = PSTORE_FLAGS_DMESG;
if (cxt->console_size)
@@ -855,9 +842,9 @@ static int ramoops_probe(struct platform_device *pdev)
ramoops_pmsg_size = pdata->pmsg_size;
ramoops_ftrace_size = pdata->ftrace_size;
- pr_info("attached 0x%lx@0x%llx, ecc: %d/%d\n",
+ pr_info("using 0x%lx@0x%llx, ecc: %d\n",
cxt->size, (unsigned long long)cxt->phys_addr,
- cxt->ecc_info.ecc_size, cxt->ecc_info.block_size);
+ cxt->ecc_info.ecc_size);
return 0;
diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 12e21f7..c11711c 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -12,7 +12,7 @@
*
*/
-#define pr_fmt(fmt) "persistent_ram: " fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/device.h>
#include <linux/err.h>
@@ -29,6 +29,16 @@
#include <linux/vmalloc.h>
#include <asm/page.h>
+/**
+ * struct persistent_ram_buffer - persistent circular RAM buffer
+ *
+ * @sig:
+ * signature to indicate header (PERSISTENT_RAM_SIG xor PRZ-type value)
+ * @start:
+ * offset into @data where the beginning of the stored bytes begin
+ * @size:
+ * number of valid bytes stored in @data
+ */
struct persistent_ram_buffer {
uint32_t sig;
atomic_t start;
@@ -443,7 +453,8 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size,
void *va;
if (!request_mem_region(start, size, label ?: "ramoops")) {
- pr_err("request mem region (0x%llx@0x%llx) failed\n",
+ pr_err("request mem region (%s 0x%llx@0x%llx) failed\n",
+ label ?: "ramoops",
(unsigned long long)size, (unsigned long long)start);
return NULL;
}
@@ -489,32 +500,42 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig,
struct persistent_ram_ecc_info *ecc_info)
{
int ret;
+ bool zap = !!(prz->flags & PRZ_FLAG_ZAP_OLD);
ret = persistent_ram_init_ecc(prz, ecc_info);
- if (ret)
+ if (ret) {
+ pr_warn("ECC failed %s\n", prz->label);
return ret;
+ }
sig ^= PERSISTENT_RAM_SIG;
if (prz->buffer->sig == sig) {
+ if (buffer_size(prz) == 0) {
+ pr_debug("found existing empty buffer\n");
+ return 0;
+ }
+
if (buffer_size(prz) > prz->buffer_size ||
- buffer_start(prz) > buffer_size(prz))
+ buffer_start(prz) > buffer_size(prz)) {
pr_info("found existing invalid buffer, size %zu, start %zu\n",
buffer_size(prz), buffer_start(prz));
- else {
+ zap = true;
+ } else {
pr_debug("found existing buffer, size %zu, start %zu\n",
buffer_size(prz), buffer_start(prz));
persistent_ram_save_old(prz);
- return 0;
}
} else {
pr_debug("no valid data in buffer (sig = 0x%08x)\n",
prz->buffer->sig);
+ prz->buffer->sig = sig;
+ zap = true;
}
- /* Rewind missing or invalid memory area. */
- prz->buffer->sig = sig;
- persistent_ram_zap(prz);
+ /* Reset missing, invalid, or single-use memory area. */
+ if (zap)
+ persistent_ram_zap(prz);
return 0;
}
@@ -572,6 +593,12 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
if (ret)
goto err;
+ pr_debug("attached %s 0x%zx@0x%llx: %zu header, %zu data, %zu ecc (%d/%d)\n",
+ prz->label, prz->size, (unsigned long long)prz->paddr,
+ sizeof(*prz->buffer), prz->buffer_size,
+ prz->size - sizeof(*prz->buffer) - prz->buffer_size,
+ prz->ecc_info.ecc_size, prz->ecc_info.block_size);
+
return prz;
err:
persistent_ram_free(prz);
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 30fcec3..b146181 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -26,27 +26,38 @@
#include <linux/errno.h>
#include <linux/kmsg_dump.h>
#include <linux/mutex.h>
-#include <linux/spinlock.h>
+#include <linux/semaphore.h>
#include <linux/time.h>
#include <linux/types.h>
struct module;
-/* pstore record types (see fs/pstore/inode.c for filename templates) */
+/*
+ * pstore record types (see fs/pstore/platform.c for pstore_type_names[])
+ * These values may be written to storage (see EFI vars backend), so
+ * they are kind of an ABI. Be careful changing the mappings.
+ */
enum pstore_type_id {
+ /* Frontend storage types */
PSTORE_TYPE_DMESG = 0,
PSTORE_TYPE_MCE = 1,
PSTORE_TYPE_CONSOLE = 2,
PSTORE_TYPE_FTRACE = 3,
- /* PPC64 partition types */
+
+ /* PPC64-specific partition types */
PSTORE_TYPE_PPC_RTAS = 4,
PSTORE_TYPE_PPC_OF = 5,
PSTORE_TYPE_PPC_COMMON = 6,
PSTORE_TYPE_PMSG = 7,
PSTORE_TYPE_PPC_OPAL = 8,
- PSTORE_TYPE_UNKNOWN = 255
+
+ /* End of the list */
+ PSTORE_TYPE_MAX
};
+const char *pstore_type_to_name(enum pstore_type_id type);
+enum pstore_type_id pstore_name_to_type(const char *name);
+
struct pstore_info;
/**
* struct pstore_record - details of a pstore record entry
@@ -85,10 +96,10 @@ struct pstore_record {
/**
* struct pstore_info - backend pstore driver structure
*
- * @owner: module which is repsonsible for this backend driver
+ * @owner: module which is responsible for this backend driver
* @name: name of the backend driver
*
- * @buf_lock: spinlock to serialize access to @buf
+ * @buf_lock: semaphore to serialize access to @buf
* @buf: preallocated crash dump buffer
* @bufsize: size of @buf available for crash dump bytes (must match
* smallest number of bytes available for writing to a
@@ -173,7 +184,7 @@ struct pstore_info {
struct module *owner;
char *name;
- spinlock_t buf_lock;
+ struct semaphore buf_lock;
char *buf;
size_t bufsize;
@@ -192,14 +203,13 @@ struct pstore_info {
};
/* Supported frontends */
-#define PSTORE_FLAGS_DMESG (1 << 0)
-#define PSTORE_FLAGS_CONSOLE (1 << 1)
-#define PSTORE_FLAGS_FTRACE (1 << 2)
-#define PSTORE_FLAGS_PMSG (1 << 3)
+#define PSTORE_FLAGS_DMESG BIT(0)
+#define PSTORE_FLAGS_CONSOLE BIT(1)
+#define PSTORE_FLAGS_FTRACE BIT(2)
+#define PSTORE_FLAGS_PMSG BIT(3)
extern int pstore_register(struct pstore_info *);
extern void pstore_unregister(struct pstore_info *);
-extern bool pstore_cannot_block_path(enum kmsg_dump_reason reason);
struct pstore_ftrace_record {
unsigned long ip;
diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h
index 602d647..337971c 100644
--- a/include/linux/pstore_ram.h
+++ b/include/linux/pstore_ram.h
@@ -22,6 +22,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/pstore.h>
#include <linux/types.h>
/*
@@ -30,6 +31,11 @@
* PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required.
*/
#define PRZ_FLAG_NO_LOCK BIT(0)
+/*
+ * If a PRZ should only have a single-boot lifetime, this marks it as
+ * getting wiped after its contents get copied out after boot.
+ */
+#define PRZ_FLAG_ZAP_OLD BIT(1)
struct persistent_ram_buffer;
struct rs_control;
@@ -42,17 +48,55 @@ struct persistent_ram_ecc_info {
uint16_t *par;
};
+/**
+ * struct persistent_ram_zone - Details of a persistent RAM zone (PRZ)
+ * used as a pstore backend
+ *
+ * @paddr: physical address of the mapped RAM area
+ * @size: size of mapping
+ * @label: unique name of this PRZ
+ * @type: frontend type for this PRZ
+ * @flags: holds PRZ_FLAGS_* bits
+ *
+ * @buffer_lock:
+ * locks access to @buffer "size" bytes and "start" offset
+ * @buffer:
+ * pointer to actual RAM area managed by this PRZ
+ * @buffer_size:
+ * bytes in @buffer->data (not including any trailing ECC bytes)
+ *
+ * @par_buffer:
+ * pointer into @buffer->data containing ECC bytes for @buffer->data
+ * @par_header:
+ * pointer into @buffer->data containing ECC bytes for @buffer header
+ * (i.e. all fields up to @data)
+ * @rs_decoder:
+ * RSLIB instance for doing ECC calculations
+ * @corrected_bytes:
+ * ECC corrected bytes accounting since boot
+ * @bad_blocks:
+ * ECC uncorrectable bytes accounting since boot
+ * @ecc_info:
+ * ECC configuration details
+ *
+ * @old_log:
+ * saved copy of @buffer->data prior to most recent wipe
+ * @old_log_size:
+ * bytes contained in @old_log
+ *
+ */
struct persistent_ram_zone {
phys_addr_t paddr;
size_t size;
void *vaddr;
char *label;
+ enum pstore_type_id type;
+ u32 flags;
+
+ raw_spinlock_t buffer_lock;
struct persistent_ram_buffer *buffer;
size_t buffer_size;
- u32 flags;
- raw_spinlock_t buffer_lock;
- /* ECC correction */
char *par_buffer;
char *par_header;
struct rs_control *rs_decoder;
