Merge branch 'pstore-efi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
authorLinus Torvalds <torvalds@linux-foundation.org>
Mon, 1 Aug 2011 23:40:51 +0000 (13:40 -1000)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 1 Aug 2011 23:40:51 +0000 (13:40 -1000)
* '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

Documentation/ABI/testing/pstore
Documentation/kernel-parameters.txt
drivers/acpi/apei/erst.c
drivers/firmware/efivars.c
fs/pstore/inode.c
fs/pstore/internal.h
fs/pstore/platform.c
include/linux/efi.h
include/linux/pstore.h

index ddf451e..ff1df4e 100644 (file)
@@ -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.
+
index 4ca9389..26a8374 100644 (file)
@@ -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.
 
index e6cef8e..6053f47 100644 (file)
@@ -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;
index 5f29aaf..eacb05e 100644 (file)
@@ -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);
 
index 977ed27..893b961 100644 (file)
@@ -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:
index 8c9f23e..611c1b3 100644 (file)
@@ -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);
index f2c3ff2..c5300ec 100644 (file)
@@ -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");
index ec25726..2362a0b 100644 (file)
@@ -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,
index 2455ef2..cc03bbf 100644 (file)
@@ -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