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authorLinus Torvalds <torvalds@linux-foundation.org>2011-08-01 13:40:51 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2011-08-01 13:40:51 -1000
commita2d773023552f68baa2db2226dfd6d761c0df5da (patch)
treec905702c4f318d0e569222187472289c574bde3c
parent72f9adfd20e3be8a33ff3ef96cec787ed97b9ba9 (diff)
parent7644c16c7e7431fa398e834109dbb76dc1b51617 (diff)
Merge branch 'pstore-efi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'pstore-efi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: efivars: Introduce PSTORE_EFI_ATTRIBUTES efivars: Use string functions in pstore_write efivars: introduce utf16_strncmp efivars: String functions efi: Add support for using efivars as a pstore backend pstore: Allow the user to explicitly choose a backend pstore: Make "part" unsigned pstore: Add extra context for writes and erases pstore: Extend API for more flexibility in new backends
-rw-r--r--Documentation/ABI/testing/pstore6
-rw-r--r--Documentation/kernel-parameters.txt2
-rw-r--r--drivers/acpi/apei/erst.c20
-rw-r--r--drivers/firmware/efivars.c243
-rw-r--r--fs/pstore/inode.c12
-rw-r--r--fs/pstore/internal.h2
-rw-r--r--fs/pstore/platform.c30
-rw-r--r--include/linux/efi.h6
-rw-r--r--include/linux/pstore.h9
9 files changed, 296 insertions, 34 deletions
diff --git a/Documentation/ABI/testing/pstore b/Documentation/ABI/testing/pstore
index ddf451ee2a08..ff1df4e3b059 100644
--- a/Documentation/ABI/testing/pstore
+++ b/Documentation/ABI/testing/pstore
@@ -39,3 +39,9 @@ Description: Generic interface to platform dependent persistent storage.
multiple) files based on the record size of the underlying
persistent storage until at least this amount is reached.
Default is 10 Kbytes.
+
+ Pstore only supports one backend at a time. If multiple
+ backends are available, the preferred backend may be
+ set by passing the pstore.backend= argument to the kernel at
+ boot time.
+
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 4ca93898fbd3..26a83743af19 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2153,6 +2153,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
[HW,MOUSE] Controls Logitech smartscroll autorepeat.
0 = disabled, 1 = enabled (default).
+ pstore.backend= Specify the name of the pstore backend to use
+
pt. [PARIDE]
See Documentation/blockdev/paride.txt.
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index e6cef8e1b534..6053f4780df9 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -932,8 +932,11 @@ static int erst_check_table(struct acpi_table_erst *erst_tab)
static int erst_open_pstore(struct pstore_info *psi);
static int erst_close_pstore(struct pstore_info *psi);
static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
- struct timespec *time);
-static u64 erst_writer(enum pstore_type_id type, size_t size);
+ struct timespec *time, struct pstore_info *psi);
+static u64 erst_writer(enum pstore_type_id type, unsigned int part,
+ size_t size, struct pstore_info *psi);
+static int erst_clearer(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi);
static struct pstore_info erst_info = {
.owner = THIS_MODULE,
@@ -942,7 +945,7 @@ static struct pstore_info erst_info = {
.close = erst_close_pstore,
.read = erst_reader,
.write = erst_writer,
- .erase = erst_clear
+ .erase = erst_clearer
};
#define CPER_CREATOR_PSTORE \
@@ -983,7 +986,7 @@ static int erst_close_pstore(struct pstore_info *psi)
}
static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
- struct timespec *time)
+ struct timespec *time, struct pstore_info *psi)
{
int rc;
ssize_t len = 0;
@@ -1037,7 +1040,8 @@ out:
return (rc < 0) ? rc : (len - sizeof(*rcd));
}
-static u64 erst_writer(enum pstore_type_id type, size_t size)
+static u64 erst_writer(enum pstore_type_id type, unsigned int part,
+ size_t size, struct pstore_info *psi)
{
struct cper_pstore_record *rcd = (struct cper_pstore_record *)
(erst_info.buf - sizeof(*rcd));
@@ -1080,6 +1084,12 @@ static u64 erst_writer(enum pstore_type_id type, size_t size)
return rcd->hdr.record_id;
}
+static int erst_clearer(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ return erst_clear(id);
+}
+
static int __init erst_init(void)
{
int rc = 0;
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 5f29aafd4462..eacb05e6cfb3 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -78,6 +78,7 @@
#include <linux/kobject.h>
#include <linux/device.h>
#include <linux/slab.h>
+#include <linux/pstore.h>
#include <asm/uaccess.h>
@@ -89,6 +90,8 @@ MODULE_DESCRIPTION("sysfs interface to EFI Variables");
MODULE_LICENSE("GPL");
MODULE_VERSION(EFIVARS_VERSION);
+#define DUMP_NAME_LEN 52
+
/*
* The maximum size of VariableName + Data = 1024
* Therefore, it's reasonable to save that much
@@ -119,6 +122,10 @@ struct efivar_attribute {
ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
};
+#define PSTORE_EFI_ATTRIBUTES \
+ (EFI_VARIABLE_NON_VOLATILE | \
+ EFI_VARIABLE_BOOTSERVICE_ACCESS | \
+ EFI_VARIABLE_RUNTIME_ACCESS)
#define EFIVAR_ATTR(_name, _mode, _show, _store) \
struct efivar_attribute efivar_attr_##_name = { \
@@ -141,38 +148,72 @@ efivar_create_sysfs_entry(struct efivars *efivars,
/* Return the number of unicode characters in data */
static unsigned long
-utf8_strlen(efi_char16_t *data, unsigned long maxlength)
+utf16_strnlen(efi_char16_t *s, size_t maxlength)
{
unsigned long length = 0;
- while (*data++ != 0 && length < maxlength)
+ while (*s++ != 0 && length < maxlength)
length++;
return length;
}
+static unsigned long
+utf16_strlen(efi_char16_t *s)
+{
+ return utf16_strnlen(s, ~0UL);
+}
+
/*
* Return the number of bytes is the length of this string
* Note: this is NOT the same as the number of unicode characters
*/
static inline unsigned long
-utf8_strsize(efi_char16_t *data, unsigned long maxlength)
+utf16_strsize(efi_char16_t *data, unsigned long maxlength)
{
- return utf8_strlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
+ return utf16_strnlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
+}
+
+static inline int
+utf16_strncmp(const efi_char16_t *a, const efi_char16_t *b, size_t len)
+{
+ while (1) {
+ if (len == 0)
+ return 0;
+ if (*a < *b)
+ return -1;
+ if (*a > *b)
+ return 1;
+ if (*a == 0) /* implies *b == 0 */
+ return 0;
+ a++;
+ b++;
+ len--;
+ }
}
static efi_status_t
-get_var_data(struct efivars *efivars, struct efi_variable *var)
+get_var_data_locked(struct efivars *efivars, struct efi_variable *var)
{
efi_status_t status;
- spin_lock(&efivars->lock);
var->DataSize = 1024;
status = efivars->ops->get_variable(var->VariableName,
&var->VendorGuid,
&var->Attributes,
&var->DataSize,
var->Data);
+ return status;
+}
+
+static efi_status_t
+get_var_data(struct efivars *efivars, struct efi_variable *var)
+{
+ efi_status_t status;
+
+ spin_lock(&efivars->lock);
+ status = get_var_data_locked(efivars, var);
spin_unlock(&efivars->lock);
+
if (status != EFI_SUCCESS) {
printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n",
status);
@@ -387,12 +428,180 @@ static struct kobj_type efivar_ktype = {
.default_attrs = def_attrs,
};
+static struct pstore_info efi_pstore_info;
+
static inline void
efivar_unregister(struct efivar_entry *var)
{
kobject_put(&var->kobj);
}
+#ifdef CONFIG_PSTORE
+
+static int efi_pstore_open(struct pstore_info *psi)
+{
+ struct efivars *efivars = psi->data;
+
+ spin_lock(&efivars->lock);
+ efivars->walk_entry = list_first_entry(&efivars->list,
+ struct efivar_entry, list);
+ return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+ struct efivars *efivars = psi->data;
+
+ spin_unlock(&efivars->lock);
+ return 0;
+}
+
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+ struct timespec *timespec, struct pstore_info *psi)
+{
+ efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+ struct efivars *efivars = psi->data;
+ char name[DUMP_NAME_LEN];
+ int i;
+ unsigned int part, size;
+ unsigned long time;
+
+ while (&efivars->walk_entry->list != &efivars->list) {
+ if (!efi_guidcmp(efivars->walk_entry->var.VendorGuid,
+ vendor)) {
+ for (i = 0; i < DUMP_NAME_LEN; i++) {
+ name[i] = efivars->walk_entry->var.VariableName[i];
+ }
+ if (sscanf(name, "dump-type%u-%u-%lu", type, &part, &time) == 3) {
+ *id = part;
+ timespec->tv_sec = time;
+ timespec->tv_nsec = 0;
+ get_var_data_locked(efivars, &efivars->walk_entry->var);
+ size = efivars->walk_entry->var.DataSize;
+ memcpy(psi->buf, efivars->walk_entry->var.Data, size);
+ efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ return size;
+ }
+ }
+ efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ }
+ return 0;
+}
+
+static u64 efi_pstore_write(enum pstore_type_id type, unsigned int part,
+ size_t size, struct pstore_info *psi)
+{
+ char name[DUMP_NAME_LEN];
+ char stub_name[DUMP_NAME_LEN];
+ efi_char16_t efi_name[DUMP_NAME_LEN];
+ efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+ struct efivars *efivars = psi->data;
+ struct efivar_entry *entry, *found = NULL;
+ int i;
+
+ sprintf(stub_name, "dump-type%u-%u-", type, part);
+ sprintf(name, "%s%lu", stub_name, get_seconds());
+
+ spin_lock(&efivars->lock);
+
+ for (i = 0; i < DUMP_NAME_LEN; i++)
+ efi_name[i] = stub_name[i];
+
+ /*
+ * Clean up any entries with the same name
+ */
+
+ list_for_each_entry(entry, &efivars->list, list) {
+ get_var_data_locked(efivars, &entry->var);
+
+ if (efi_guidcmp(entry->var.VendorGuid, vendor))
+ continue;
+ if (utf16_strncmp(entry->var.VariableName, efi_name,
+ utf16_strlen(efi_name)))
+ continue;
+ /* Needs to be a prefix */
+ if (entry->var.VariableName[utf16_strlen(efi_name)] == 0)
+ continue;
+
+ /* found */
+ found = entry;
+ efivars->ops->set_variable(entry->var.VariableName,
+ &entry->var.VendorGuid,
+ PSTORE_EFI_ATTRIBUTES,
+ 0, NULL);
+ }
+
+ if (found)
+ list_del(&found->list);
+
+ for (i = 0; i < DUMP_NAME_LEN; i++)
+ efi_name[i] = name[i];
+
+ efivars->ops->set_variable(efi_name, &vendor, PSTORE_EFI_ATTRIBUTES,
+ size, psi->buf);
+
+ spin_unlock(&efivars->lock);
+
+ if (found)
+ efivar_unregister(found);
+
+ if (size)
+ efivar_create_sysfs_entry(efivars,
+ utf16_strsize(efi_name,
+ DUMP_NAME_LEN * 2),
+ efi_name, &vendor);
+
+ return part;
+};
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ efi_pstore_write(type, id, 0, psi);
+
+ return 0;
+}
+#else
+static int efi_pstore_open(struct pstore_info *psi)
+{
+ return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+ return 0;
+}
+
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+ struct timespec *time, struct pstore_info *psi)
+{
+ return -1;
+}
+
+static u64 efi_pstore_write(enum pstore_type_id type, int part, size_t size,
+ struct pstore_info *psi)
+{
+ return 0;
+}
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ return 0;
+}
+#endif
+
+static struct pstore_info efi_pstore_info = {
+ .owner = THIS_MODULE,
+ .name = "efi",
+ .open = efi_pstore_open,
+ .close = efi_pstore_close,
+ .read = efi_pstore_read,
+ .write = efi_pstore_write,
+ .erase = efi_pstore_erase,
+};
static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
@@ -414,8 +623,8 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
- strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
- strsize2 = utf8_strsize(new_var->VariableName, 1024);
+ strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
+ strsize2 = utf16_strsize(new_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
new_var->VariableName, strsize1) &&
@@ -447,8 +656,8 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
/* Create the entry in sysfs. Locking is not required here */
status = efivar_create_sysfs_entry(efivars,
- utf8_strsize(new_var->VariableName,
- 1024),
+ utf16_strsize(new_var->VariableName,
+ 1024),
new_var->VariableName,
&new_var->VendorGuid);
if (status) {
@@ -477,8 +686,8 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
- strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
- strsize2 = utf8_strsize(del_var->VariableName, 1024);
+ strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
+ strsize2 = utf16_strsize(del_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
del_var->VariableName, strsize1) &&
@@ -763,6 +972,16 @@ int register_efivars(struct efivars *efivars,
if (error)
unregister_efivars(efivars);
+ efivars->efi_pstore_info = efi_pstore_info;
+
+ efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
+ if (efivars->efi_pstore_info.buf) {
+ efivars->efi_pstore_info.bufsize = 1024;
+ efivars->efi_pstore_info.data = efivars;
+ mutex_init(&efivars->efi_pstore_info.buf_mutex);
+ pstore_register(&efivars->efi_pstore_info);
+ }
+
out:
kfree(variable_name);
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 977ed2723845..893b961dcfd8 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -39,8 +39,9 @@
#define PSTORE_NAMELEN 64
struct pstore_private {
+ struct pstore_info *psi;
+ enum pstore_type_id type;
u64 id;
- int (*erase)(u64);
ssize_t size;
char data[];
};
@@ -73,7 +74,7 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry)
{
struct pstore_private *p = dentry->d_inode->i_private;
- p->erase(p->id);
+ p->psi->erase(p->type, p->id, p->psi);
return simple_unlink(dir, dentry);
}
@@ -175,8 +176,8 @@ int pstore_is_mounted(void)
* Set the mtime & ctime to the date that this record was originally stored.
*/
int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
- char *data, size_t size,
- struct timespec time, int (*erase)(u64))
+ char *data, size_t size, struct timespec time,
+ struct pstore_info *psi)
{
struct dentry *root = pstore_sb->s_root;
struct dentry *dentry;
@@ -192,8 +193,9 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
private = kmalloc(sizeof *private + size, GFP_KERNEL);
if (!private)
goto fail_alloc;
+ private->type = type;
private->id = id;
- private->erase = erase;
+ private->psi = psi;
switch (type) {
case PSTORE_TYPE_DMESG:
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index 8c9f23eb1645..611c1b3c46fa 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -2,5 +2,5 @@ extern void pstore_set_kmsg_bytes(int);
extern void pstore_get_records(void);
extern int pstore_mkfile(enum pstore_type_id, char *psname, u64 id,
char *data, size_t size,
- struct timespec time, int (*erase)(u64));
+ struct timespec time, struct pstore_info *psi);
extern int pstore_is_mounted(void);
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index f2c3ff20ea68..c5300ec31696 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -37,6 +37,8 @@
static DEFINE_SPINLOCK(pstore_lock);
static struct pstore_info *psinfo;
+static char *backend;
+
/* How much of the console log to snapshot */
static unsigned long kmsg_bytes = 10240;
@@ -67,7 +69,8 @@ static void pstore_dump(struct kmsg_dumper *dumper,
unsigned long size, total = 0;
char *dst, *why;
u64 id;
- int hsize, part = 1;
+ int hsize;
+ unsigned int part = 1;
if (reason < ARRAY_SIZE(reason_str))
why = reason_str[reason];
@@ -78,7 +81,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
oopscount++;
while (total < kmsg_bytes) {
dst = psinfo->buf;
- hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part++);
+ hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part);
size = psinfo->bufsize - hsize;
dst += hsize;
@@ -94,14 +97,16 @@ static void pstore_dump(struct kmsg_dumper *dumper,
memcpy(dst, s1 + s1_start, l1_cpy);
memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy);
- id = psinfo->write(PSTORE_TYPE_DMESG, hsize + l1_cpy + l2_cpy);
+ id = psinfo->write(PSTORE_TYPE_DMESG, part,
+ hsize + l1_cpy + l2_cpy, psinfo);
if (reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id,
psinfo->buf, hsize + l1_cpy + l2_cpy,
- CURRENT_TIME, psinfo->erase);
+ CURRENT_TIME, psinfo);
l1 -= l1_cpy;
l2 -= l2_cpy;
total += l1_cpy + l2_cpy;
+ part++;
}
mutex_unlock(&psinfo->buf_mutex);
}
@@ -128,6 +133,12 @@ int pstore_register(struct pstore_info *psi)
spin_unlock(&pstore_lock);
return -EBUSY;
}
+
+ if (backend && strcmp(backend, psi->name)) {
+ spin_unlock(&pstore_lock);
+ return -EINVAL;
+ }
+
psinfo = psi;
spin_unlock(&pstore_lock);
@@ -166,9 +177,9 @@ void pstore_get_records(void)
if (rc)
goto out;
- while ((size = psi->read(&id, &type, &time)) > 0) {
+ while ((size = psi->read(&id, &type, &time, psi)) > 0) {
if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size,
- time, psi->erase))
+ time, psi))
failed++;
}
psi->close(psi);
@@ -196,12 +207,15 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size)
mutex_lock(&psinfo->buf_mutex);
memcpy(psinfo->buf, buf, size);
- id = psinfo->write(type, size);
+ id = psinfo->write(type, 0, size, psinfo);
if (pstore_is_mounted())
pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf,
- size, CURRENT_TIME, psinfo->erase);
+ size, CURRENT_TIME, psinfo);
mutex_unlock(&psinfo->buf_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(pstore_write);
+
+module_param(backend, charp, 0444);
+MODULE_PARM_DESC(backend, "Pstore backend to use");
diff --git a/include/linux/efi.h b/include/linux/efi.h
index ec2572693925..2362a0bc7f0d 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -19,6 +19,7 @@
#include <linux/rtc.h>
#include <linux/ioport.h>
#include <linux/pfn.h>
+#include <linux/pstore.h>
#include <asm/page.h>
#include <asm/system.h>
@@ -232,6 +233,9 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
#define UV_SYSTEM_TABLE_GUID \
EFI_GUID( 0x3b13a7d4, 0x633e, 0x11dd, 0x93, 0xec, 0xda, 0x25, 0x56, 0xd8, 0x95, 0x93 )
+#define LINUX_EFI_CRASH_GUID \
+ EFI_GUID( 0xcfc8fc79, 0xbe2e, 0x4ddc, 0x97, 0xf0, 0x9f, 0x98, 0xbf, 0xe2, 0x98, 0xa0 )
+
typedef struct {
efi_guid_t guid;
unsigned long table;
@@ -458,6 +462,8 @@ struct efivars {
struct kset *kset;
struct bin_attribute *new_var, *del_var;
const struct efivar_operations *ops;
+ struct efivar_entry *walk_entry;
+ struct pstore_info efi_pstore_info;
};
int register_efivars(struct efivars *efivars,
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 2455ef2683f0..cc03bbf5c4b8 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -38,9 +38,12 @@ struct pstore_info {
int (*open)(struct pstore_info *psi);
int (*close)(struct pstore_info *psi);
ssize_t (*read)(u64 *id, enum pstore_type_id *type,
- struct timespec *time);
- u64 (*write)(enum pstore_type_id type, size_t size);
- int (*erase)(u64 id);
+ struct timespec *time, struct pstore_info *psi);
+ u64 (*write)(enum pstore_type_id type, unsigned int part,
+ size_t size, struct pstore_info *psi);
+ int (*erase)(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi);
+ void *data;
};
#ifdef CONFIG_PSTORE