/*
* platform specific persistent storage driver registers with
* us here. If pstore is already mounted, call the platform
* read function right away to populate the file system. If not
* then the pstore mount code will call us later to fill out
* the file system.
*
* Register with kmsg_dump to save last part of console log on panic.
*/
int pstore_register(struct pstore_info *psi)
{
struct module *owner = psi->owner;
spin_lock(&pstore_lock);
if (psinfo) {
spin_unlock(&pstore_lock);
return -EBUSY;
}
if (backend && strcmp(backend, psi->name)) {
spin_unlock(&pstore_lock);
return -EINVAL;
}
psinfo = psi;
mutex_init(&psinfo->read_mutex);
spin_unlock(&pstore_lock);
if (owner && !try_module_get(owner)) {
psinfo = NULL;
return -EINVAL;
}
if (pstore_is_mounted())
pstore_get_records(0);
kmsg_dump_register(&pstore_dumper);
pstore_timer.expires = jiffies + PSTORE_INTERVAL;
add_timer(&pstore_timer);
return 0;
}
/*
* platform specific persistent storage driver registers with
* us here. If pstore is already mounted, call the platform
* read function right away to populate the file system. If not
* then the pstore mount code will call us later to fill out
* the file system.
*
* Register with kmsg_dump to save last part of console log on panic.
*/
int pstore_register(struct pstore_info *psi)
{
struct module *owner = psi->owner;
spin_lock(&pstore_lock);
if (psinfo) {
spin_unlock(&pstore_lock);
return -EBUSY;
}
if (backend && strcmp(backend, psi->name)) {
spin_unlock(&pstore_lock);
return -EINVAL;
}
psinfo = psi;
spin_unlock(&pstore_lock);
if (owner && !try_module_get(owner)) {
psinfo = NULL;
return -EINVAL;
}
if (pstore_is_mounted())
pstore_get_records();
kmsg_dump_register(&pstore_dumper);
return 0;
}
/*
* 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.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason,
const char *s1, unsigned long l1,
const char *s2, unsigned long l2)
{
unsigned long s1_start, s2_start;
unsigned long l1_cpy, l2_cpy;
unsigned long size, total = 0;
char *dst;
const char *why;
u64 id;
int hsize, ret;
unsigned int part = 1;
unsigned long flags = 0;
int is_locked = 0;
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);
}
} else
spin_lock_irqsave(&psinfo->buf_lock, flags);
oopscount++;
while (total < kmsg_bytes) {
dst = psinfo->buf;
hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part);
size = psinfo->bufsize - hsize;
dst += hsize;
l2_cpy = min(l2, size);
l1_cpy = min(l1, size - l2_cpy);
if (l1_cpy + l2_cpy == 0)
break;
s2_start = l2 - l2_cpy;
s1_start = l1 - l1_cpy;
memcpy(dst, s1 + s1_start, l1_cpy);
memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy);
ret = psinfo->write(PSTORE_TYPE_DMESG, &id, part,
hsize + l1_cpy + l2_cpy, psinfo);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
l1 -= l1_cpy;
l2 -= l2_cpy;
total += l1_cpy + l2_cpy;
part++;
}
if (pstore_cannot_block_path(reason)) {
if (is_locked)
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
} else
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
}
/*
* platform specific persistent storage driver registers with
* us here. If pstore is already mounted, call the platform
* read function right away to populate the file system. If not
* then the pstore mount code will call us later to fill out
* the file system.
*/
int pstore_register(struct pstore_info *psi)
{
struct module *owner = psi->owner;
if (backend && strcmp(backend, psi->name))
return -EPERM;
spin_lock(&pstore_lock);
if (psinfo) {
spin_unlock(&pstore_lock);
return -EBUSY;
}
if (!psi->write)
psi->write = pstore_write_compat;
if (!psi->write_buf_user)
psi->write_buf_user = pstore_write_buf_user_compat;
psinfo = psi;
mutex_init(&psinfo->read_mutex);
spin_unlock(&pstore_lock);
if (owner && !try_module_get(owner)) {
psinfo = NULL;
return -EINVAL;
}
allocate_buf_for_compression();
if (pstore_is_mounted())
pstore_get_records(0);
if (psi->flags & PSTORE_FLAGS_DMESG)
pstore_register_kmsg();
if (psi->flags & PSTORE_FLAGS_CONSOLE)
pstore_register_console();
if (psi->flags & PSTORE_FLAGS_FTRACE)
pstore_register_ftrace();
if (psi->flags & PSTORE_FLAGS_PMSG)
pstore_register_pmsg();
if (pstore_update_ms >= 0) {
pstore_timer.expires = jiffies +
msecs_to_jiffies(pstore_update_ms);
add_timer(&pstore_timer);
}
/*
* Update the module parameter backend, so it is visible
* through /sys/module/pstore/parameters/backend
*/
backend = psi->name;
module_put(owner);
pr_info("Registered %s as persistent store backend\n", psi->name);
return 0;
}
/*
* 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.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason,
const char *s1, unsigned long l1,
const char *s2, unsigned long l2)
{
unsigned long s1_start, s2_start;
unsigned long l1_cpy, l2_cpy;
unsigned long size, total = 0;
char *dst, *why;
u64 id;
int hsize;
unsigned int part = 1;
if (reason < ARRAY_SIZE(reason_str))
why = reason_str[reason];
else
why = "Unknown";
mutex_lock(&psinfo->buf_mutex);
oopscount++;
while (total < kmsg_bytes) {
dst = psinfo->buf;
hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part);
size = psinfo->bufsize - hsize;
dst += hsize;
l2_cpy = min(l2, size);
l1_cpy = min(l1, size - l2_cpy);
if (l1_cpy + l2_cpy == 0)
break;
s2_start = l2 - l2_cpy;
s1_start = l1 - l1_cpy;
memcpy(dst, s1 + s1_start, l1_cpy);
memcpy(dst + l1_cpy, s2 + s2_start, 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);
l1 -= l1_cpy;
l2 -= l2_cpy;
total += l1_cpy + l2_cpy;
part++;
}
mutex_unlock(&psinfo->buf_mutex);
}
/*
* 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.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason)
{
unsigned long total = 0;
const char *why;
u64 id;
unsigned int part = 1;
unsigned long flags = 0;
int is_locked = 0;
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);
}
} else
spin_lock_irqsave(&psinfo->buf_lock, flags);
oopscount++;
while (total < kmsg_bytes) {
char *dst;
unsigned long size;
int hsize;
size_t len;
dst = psinfo->buf;
hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part);
size = psinfo->bufsize - hsize;
dst += hsize;
if (!kmsg_dump_get_buffer(dumper, true, dst, size, &len))
break;
ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
oopscount, hsize + len, psinfo);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
total += hsize + len;
part++;
}
if (pstore_cannot_block_path(reason)) {
if (is_locked)
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
} else
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
}
/*
* platform specific persistent storage driver registers with
* us here. If pstore is already mounted, call the platform
* read function right away to populate the file system. If not
* then the pstore mount code will call us later to fill out
* the file system.
*
* Register with kmsg_dump to save last part of console log on panic.
*/
int pstore_register(struct pstore_info *psi)
{
struct module *owner = psi->owner;
spin_lock(&pstore_lock);
if (psinfo) {
spin_unlock(&pstore_lock);
return -EBUSY;
}
if (backend && strcmp(backend, psi->name)) {
spin_unlock(&pstore_lock);
return -EINVAL;
}
if (!psi->write)
psi->write = pstore_write_compat;
psinfo = psi;
mutex_init(&psinfo->read_mutex);
spin_unlock(&pstore_lock);
if (owner && !try_module_get(owner)) {
psinfo = NULL;
return -EINVAL;
}
if (pstore_is_mounted())
pstore_get_records(0);
kmsg_dump_register(&pstore_dumper);
pstore_register_console();
pstore_register_ftrace();
pstore_register_pmsg();
if (pstore_update_ms >= 0) {
pstore_timer.expires = jiffies +
msecs_to_jiffies(pstore_update_ms);
add_timer(&pstore_timer);
}
pr_info("psi registered\n");
return 0;
}
/*
* Call platform driver to write a record to the
* persistent store.
*/
int pstore_write(enum pstore_type_id type, char *buf, size_t size)
{
u64 id;
if (!psinfo)
return -ENODEV;
if (size > psinfo->bufsize)
return -EFBIG;
mutex_lock(&psinfo->buf_mutex);
memcpy(psinfo->buf, buf, 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);
mutex_unlock(&psinfo->buf_mutex);
return 0;
}
/*
* Call platform driver to write a record to the
* persistent store.
*/
int pstore_write(enum pstore_type_id type, char *buf, size_t size)
{
u64 id;
int ret;
unsigned long flags;
if (!psinfo)
return -ENODEV;
if (size > psinfo->bufsize)
return -EFBIG;
spin_lock_irqsave(&psinfo->buf_lock, flags);
memcpy(psinfo->buf, buf, size);
ret = psinfo->write(type, &id, 0, size, psinfo);
if (ret == 0 && pstore_is_mounted())
pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf,
size, CURRENT_TIME, psinfo);
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
return 0;
}
/*
* platform specific persistent storage driver registers with
* us here. If pstore is already mounted, call the platform
* read function right away to populate the file system. If not
* then the pstore mount code will call us later to fill out
* the file system.
*/
int pstore_register(struct pstore_info *psi)
{
struct module *owner = psi->owner;
if (backend && strcmp(backend, psi->name)) {
pr_warn("ignoring unexpected backend '%s'\n", psi->name);
return -EPERM;
}
/* Sanity check flags. */
if (!psi->flags) {
pr_warn("backend '%s' must support at least one frontend\n",
psi->name);
return -EINVAL;
}
/* Check for required functions. */
if (!psi->read || !psi->write) {
pr_warn("backend '%s' must implement read() and write()\n",
psi->name);
return -EINVAL;
}
spin_lock(&pstore_lock);
if (psinfo) {
pr_warn("backend '%s' already loaded: ignoring '%s'\n",
psinfo->name, psi->name);
spin_unlock(&pstore_lock);
return -EBUSY;
}
if (!psi->write_user)
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)) {
psinfo = NULL;
return -EINVAL;
}
allocate_buf_for_compression();
if (pstore_is_mounted())
pstore_get_records(0);
if (psi->flags & PSTORE_FLAGS_DMESG)
pstore_register_kmsg();
if (psi->flags & PSTORE_FLAGS_CONSOLE)
pstore_register_console();
if (psi->flags & PSTORE_FLAGS_FTRACE)
pstore_register_ftrace();
if (psi->flags & PSTORE_FLAGS_PMSG)
pstore_register_pmsg();
/* Start watching for new records, if desired. */
if (pstore_update_ms >= 0) {
pstore_timer.expires = jiffies +
msecs_to_jiffies(pstore_update_ms);
add_timer(&pstore_timer);
}
/*
* Update the module parameter backend, so it is visible
* through /sys/module/pstore/parameters/backend
*/
backend = psi->name;
pr_info("Registered %s as persistent store backend\n", psi->name);
module_put(owner);
return 0;
}
/*
* 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)
{
unsigned long total = 0;
const char *why;
unsigned int part = 1;
int ret;
why = get_reason_str(reason);
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;
}
if (down_interruptible(&psinfo->buf_lock)) {
pr_err("could not grab semaphore?!\n");
return;
}
}
oopscount++;
while (total < kmsg_bytes) {
char *dst;
size_t dst_size;
int header_size;
int zipped_len = -1;
size_t dump_size;
struct pstore_record record;
pstore_record_init(&record, psinfo);
record.type = PSTORE_TYPE_DMESG;
record.count = oopscount;
record.reason = reason;
record.part = part;
record.buf = psinfo->buf;
if (big_oops_buf) {
dst = big_oops_buf;
dst_size = big_oops_buf_sz;
} else {
dst = psinfo->buf;
dst_size = psinfo->bufsize;
}
/* Write dump header. */
header_size = snprintf(dst, dst_size, "%s#%d Part%u\n", why,
oopscount, part);
dst_size -= header_size;
/* Write dump contents. */
if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
dst_size, &dump_size))
break;
if (big_oops_buf) {
zipped_len = pstore_compress(dst, psinfo->buf,
header_size + dump_size,
psinfo->bufsize);
if (zipped_len > 0) {
record.compressed = true;
record.size = zipped_len;
} else {
record.size = copy_kmsg_to_buffer(header_size,
dump_size);
}
} else {
record.size = header_size + dump_size;
}
ret = psinfo->write(&record);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
total += record.size;
part++;
}
up(&psinfo->buf_lock);
}
/*
* 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.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason)
{
unsigned long total = 0;
const char *why;
u64 id;
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);
}
} else {
spin_lock_irqsave(&psinfo->buf_lock, flags);
is_locked = 1;
}
oopscount++;
while (total < kmsg_bytes) {
char *dst;
unsigned long size;
int hsize;
int zipped_len = -1;
size_t len;
bool compressed = false;
size_t total_len;
if (big_oops_buf && is_locked) {
dst = big_oops_buf;
size = big_oops_buf_sz;
} else {
dst = psinfo->buf;
size = psinfo->bufsize;
}
hsize = sprintf(dst, "%s#%d Part%u\n", why, oopscount, part);
size -= hsize;
if (!kmsg_dump_get_buffer(dumper, true, dst + hsize,
size, &len))
break;
if (big_oops_buf && is_locked) {
zipped_len = pstore_compress(dst, psinfo->buf,
hsize + len, psinfo->bufsize);
if (zipped_len > 0) {
compressed = true;
total_len = zipped_len;
} else {
total_len = copy_kmsg_to_buffer(hsize, len);
}
} else {
total_len = hsize + len;
}
ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
oopscount, compressed, total_len, psinfo);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
total += total_len;
part++;
}
if (is_locked)
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
}
