aboutsummaryrefslogtreecommitdiff
path: root/fs/pstore
diff options
context:
space:
mode:
Diffstat (limited to 'fs/pstore')
-rw-r--r--fs/pstore/Kconfig2
-rw-r--r--fs/pstore/ftrace.c2
-rw-r--r--fs/pstore/inode.c22
-rw-r--r--fs/pstore/internal.h5
-rw-r--r--fs/pstore/platform.c255
-rw-r--r--fs/pstore/ram.c69
-rw-r--r--fs/pstore/ram_core.c92
7 files changed, 370 insertions, 77 deletions
diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index ca71db69da0..983d9510bec 100644
--- a/fs/pstore/Kconfig
+++ b/fs/pstore/Kconfig
@@ -1,6 +1,8 @@
config PSTORE
bool "Persistent store support"
default n
+ select ZLIB_DEFLATE
+ select ZLIB_INFLATE
help
This option enables generic access to platform level
persistent storage via "pstore" filesystem that can
diff --git a/fs/pstore/ftrace.c b/fs/pstore/ftrace.c
index 43b12807a51..76a4eeb9298 100644
--- a/fs/pstore/ftrace.c
+++ b/fs/pstore/ftrace.c
@@ -44,7 +44,7 @@ static void notrace pstore_ftrace_call(unsigned long ip,
rec.parent_ip = parent_ip;
pstore_ftrace_encode_cpu(&rec, raw_smp_processor_id());
psinfo->write_buf(PSTORE_TYPE_FTRACE, 0, NULL, 0, (void *)&rec,
- sizeof(rec), psinfo);
+ 0, sizeof(rec), psinfo);
local_irq_restore(flags);
}
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index e4bcb2cf055..192297b0090 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -178,6 +178,8 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry)
if (p->psi->erase)
p->psi->erase(p->type, p->id, p->count,
dentry->d_inode->i_ctime, p->psi);
+ else
+ return -EPERM;
return simple_unlink(dir, dentry);
}
@@ -247,6 +249,7 @@ static void parse_options(char *options)
static int pstore_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
parse_options(data);
return 0;
@@ -273,8 +276,8 @@ 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, int count,
- char *data, size_t size, struct timespec time,
- struct pstore_info *psi)
+ char *data, bool compressed, size_t size,
+ struct timespec time, struct pstore_info *psi)
{
struct dentry *root = pstore_sb->s_root;
struct dentry *dentry;
@@ -313,7 +316,8 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
switch (type) {
case PSTORE_TYPE_DMESG:
- sprintf(name, "dmesg-%s-%lld", psname, id);
+ sprintf(name, "dmesg-%s-%lld%s", psname, id,
+ compressed ? ".enc.z" : "");
break;
case PSTORE_TYPE_CONSOLE:
sprintf(name, "console-%s", psname);
@@ -324,6 +328,15 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
case PSTORE_TYPE_MCE:
sprintf(name, "mce-%s-%lld", psname, id);
break;
+ case PSTORE_TYPE_PPC_RTAS:
+ sprintf(name, "rtas-%s-%lld", psname, id);
+ break;
+ case PSTORE_TYPE_PPC_OF:
+ sprintf(name, "powerpc-ofw-%s-%lld", psname, id);
+ break;
+ case PSTORE_TYPE_PPC_COMMON:
+ sprintf(name, "powerpc-common-%s-%lld", psname, id);
+ break;
case PSTORE_TYPE_UNKNOWN:
sprintf(name, "unknown-%s-%lld", psname, id);
break;
@@ -334,9 +347,8 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
mutex_lock(&root->d_inode->i_mutex);
- rc = -ENOSPC;
dentry = d_alloc_name(root, name);
- if (IS_ERR(dentry))
+ if (!dentry)
goto fail_lockedalloc;
memcpy(private->data, data, size);
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index 937d820f273..3b3d305277c 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -50,8 +50,9 @@ extern struct pstore_info *psinfo;
extern void pstore_set_kmsg_bytes(int);
extern void pstore_get_records(int);
extern int pstore_mkfile(enum pstore_type_id, char *psname, u64 id,
- int count, char *data, size_t size,
- struct timespec time, struct pstore_info *psi);
+ int count, char *data, bool compressed,
+ size_t size, struct timespec time,
+ struct pstore_info *psi);
extern int pstore_is_mounted(void);
#endif
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 86d1038b5a1..0a9b72cdfec 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -18,6 +18,8 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#define pr_fmt(fmt) "pstore: " fmt
+
#include <linux/atomic.h>
#include <linux/types.h>
#include <linux/errno.h>
@@ -26,6 +28,7 @@
#include <linux/console.h>
#include <linux/module.h>
#include <linux/pstore.h>
+#include <linux/zlib.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
@@ -65,6 +68,15 @@ struct pstore_info *psinfo;
static char *backend;
+/* Compression parameters */
+#define COMPR_LEVEL 6
+#define WINDOW_BITS 12
+#define MEM_LEVEL 4
+static struct z_stream_s stream;
+
+static char *big_oops_buf;
+static size_t big_oops_buf_sz;
+
/* How much of the console log to snapshot */
static unsigned long kmsg_bytes = 10240;
@@ -117,6 +129,140 @@ bool pstore_cannot_block_path(enum kmsg_dump_reason reason)
}
EXPORT_SYMBOL_GPL(pstore_cannot_block_path);
+/* Derived from logfs_compress() */
+static int pstore_compress(const void *in, void *out, size_t inlen,
+ size_t outlen)
+{
+ int err, ret;
+
+ ret = -EIO;
+ err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS,
+ MEM_LEVEL, Z_DEFAULT_STRATEGY);
+ if (err != Z_OK)
+ goto error;
+
+ stream.next_in = in;
+ stream.avail_in = inlen;
+ stream.total_in = 0;
+ stream.next_out = out;
+ stream.avail_out = outlen;
+ stream.total_out = 0;
+
+ err = zlib_deflate(&stream, Z_FINISH);
+ if (err != Z_STREAM_END)
+ goto error;
+
+ err = zlib_deflateEnd(&stream);
+ if (err != Z_OK)
+ goto error;
+
+ if (stream.total_out >= stream.total_in)
+ goto error;
+
+ ret = stream.total_out;
+error:
+ return ret;
+}
+
+/* Derived from logfs_uncompress */
+static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen)
+{
+ int err, ret;
+
+ ret = -EIO;
+ err = zlib_inflateInit2(&stream, WINDOW_BITS);
+ if (err != Z_OK)
+ goto error;
+
+ stream.next_in = in;
+ stream.avail_in = inlen;
+ stream.total_in = 0;
+ stream.next_out = out;
+ stream.avail_out = outlen;
+ stream.total_out = 0;
+
+ err = zlib_inflate(&stream, Z_FINISH);
+ if (err != Z_STREAM_END)
+ goto error;
+
+ err = zlib_inflateEnd(&stream);
+ if (err != Z_OK)
+ goto error;
+
+ ret = stream.total_out;
+error:
+ return ret;
+}
+
+static void allocate_buf_for_compression(void)
+{
+ size_t size;
+ size_t cmpr;
+
+ switch (psinfo->bufsize) {
+ /* buffer range for efivars */
+ case 1000 ... 2000:
+ cmpr = 56;
+ break;
+ case 2001 ... 3000:
+ cmpr = 54;
+ break;
+ case 3001 ... 3999:
+ cmpr = 52;
+ break;
+ /* buffer range for nvram, erst */
+ case 4000 ... 10000:
+ cmpr = 45;
+ break;
+ default:
+ cmpr = 60;
+ break;
+ }
+
+ big_oops_buf_sz = (psinfo->bufsize * 100) / cmpr;
+ big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
+ if (big_oops_buf) {
+ size = max(zlib_deflate_workspacesize(WINDOW_BITS, MEM_LEVEL),
+ zlib_inflate_workspacesize());
+ stream.workspace = kmalloc(size, GFP_KERNEL);
+ if (!stream.workspace) {
+ pr_err("No memory for compression workspace; skipping compression\n");
+ kfree(big_oops_buf);
+ big_oops_buf = NULL;
+ }
+ } else {
+ pr_err("No memory for uncompressed data; skipping compression\n");
+ stream.workspace = NULL;
+ }
+
+}
+
+/*
+ * Called when compression fails, since the printk buffer
+ * would be fetched for compression calling it again when
+ * compression fails would have moved the iterator of
+ * printk buffer which results in fetching old contents.
+ * Copy the recent messages from big_oops_buf to psinfo->buf
+ */
+static size_t copy_kmsg_to_buffer(int hsize, size_t len)
+{
+ size_t total_len;
+ size_t diff;
+
+ total_len = hsize + len;
+
+ if (total_len > psinfo->bufsize) {
+ diff = total_len - psinfo->bufsize + hsize;
+ memcpy(psinfo->buf, big_oops_buf, hsize);
+ memcpy(psinfo->buf + hsize, big_oops_buf + diff,
+ psinfo->bufsize - hsize);
+ total_len = psinfo->bufsize;
+ } else
+ memcpy(psinfo->buf, big_oops_buf, total_len);
+
+ return total_len;
+}
+
/*
* callback from kmsg_dump. (s2,l2) has the most recently
* written bytes, older bytes are in (s1,l1). Save as much
@@ -148,22 +294,52 @@ static void pstore_dump(struct kmsg_dumper *dumper,
char *dst;
unsigned long size;
int hsize;
+ int zipped_len = -1;
size_t len;
+ bool compressed;
+ size_t total_len;
+
+ if (big_oops_buf) {
+ dst = big_oops_buf;
+ hsize = sprintf(dst, "%s#%d Part%d\n", why,
+ oopscount, part);
+ size = big_oops_buf_sz - hsize;
- 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 + hsize,
+ size, &len))
+ break;
+
+ zipped_len = pstore_compress(dst, psinfo->buf,
+ hsize + len, psinfo->bufsize);
+
+ if (zipped_len > 0) {
+ compressed = true;
+ total_len = zipped_len;
+ } else {
+ compressed = false;
+ total_len = copy_kmsg_to_buffer(hsize, len);
+ }
+ } else {
+ 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;
- if (!kmsg_dump_get_buffer(dumper, true, dst, size, &len))
- break;
+ compressed = false;
+ total_len = hsize + len;
+ }
ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
- oopscount, hsize + len, psinfo);
+ oopscount, compressed, total_len, psinfo);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
- total += hsize + len;
+ total += total_len;
part++;
}
if (pstore_cannot_block_path(reason)) {
@@ -196,7 +372,7 @@ static void pstore_console_write(struct console *con, const char *s, unsigned c)
spin_lock_irqsave(&psinfo->buf_lock, flags);
}
memcpy(psinfo->buf, s, c);
- psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, c, psinfo);
+ psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, 0, c, psinfo);
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
s += c;
c = e - s;
@@ -221,9 +397,11 @@ static void pstore_register_console(void) {}
static int pstore_write_compat(enum pstore_type_id type,
enum kmsg_dump_reason reason,
u64 *id, unsigned int part, int count,
- size_t size, struct pstore_info *psi)
+ bool compressed, size_t size,
+ struct pstore_info *psi)
{
- return psi->write_buf(type, reason, id, part, psinfo->buf, size, psi);
+ return psi->write_buf(type, reason, id, part, psinfo->buf, compressed,
+ size, psi);
}
/*
@@ -239,17 +417,15 @@ 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 (backend && strcmp(backend, psi->name)) {
- spin_unlock(&pstore_lock);
- return -EINVAL;
- }
-
if (!psi->write)
psi->write = pstore_write_compat;
psinfo = psi;
@@ -261,12 +437,17 @@ int pstore_register(struct pstore_info *psi)
return -EINVAL;
}
+ allocate_buf_for_compression();
+
if (pstore_is_mounted())
pstore_get_records(0);
kmsg_dump_register(&pstore_dumper);
- pstore_register_console();
- pstore_register_ftrace();
+
+ if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) {
+ pstore_register_console();
+ pstore_register_ftrace();
+ }
if (pstore_update_ms >= 0) {
pstore_timer.expires = jiffies +
@@ -274,6 +455,8 @@ int pstore_register(struct pstore_info *psi)
add_timer(&pstore_timer);
}
+ pr_info("Registered %s as persistent store backend\n", psi->name);
+
return 0;
}
EXPORT_SYMBOL_GPL(pstore_register);
@@ -294,6 +477,8 @@ void pstore_get_records(int quiet)
enum pstore_type_id type;
struct timespec time;
int failed = 0, rc;
+ bool compressed;
+ int unzipped_len = -1;
if (!psi)
return;
@@ -302,11 +487,33 @@ void pstore_get_records(int quiet)
if (psi->open && psi->open(psi))
goto out;
- while ((size = psi->read(&id, &type, &count, &time, &buf, psi)) > 0) {
+ while ((size = psi->read(&id, &type, &count, &time, &buf, &compressed,
+ psi)) > 0) {
+ if (compressed && (type == PSTORE_TYPE_DMESG)) {
+ if (big_oops_buf)
+ unzipped_len = pstore_decompress(buf,
+ big_oops_buf, size,
+ big_oops_buf_sz);
+
+ if (unzipped_len > 0) {
+ kfree(buf);
+ buf = big_oops_buf;
+ size = unzipped_len;
+ compressed = false;
+ } else {
+ pr_err("decompression failed;returned %d\n",
+ unzipped_len);
+ compressed = true;
+ }
+ }
rc = pstore_mkfile(type, psi->name, id, count, buf,
- (size_t)size, time, psi);
- kfree(buf);
- buf = NULL;
+ compressed, (size_t)size, time, psi);
+ if (unzipped_len < 0) {
+ /* Free buffer other than big oops */
+ kfree(buf);
+ buf = NULL;
+ } else
+ unzipped_len = -1;
if (rc && (rc != -EEXIST || !quiet))
failed++;
}
@@ -316,8 +523,8 @@ out:
mutex_unlock(&psi->read_mutex);
if (failed)
- printk(KERN_WARNING "pstore: failed to load %d record(s) from '%s'\n",
- failed, psi->name);
+ pr_warn("failed to load %d record(s) from '%s'\n",
+ failed, psi->name);
}
static void pstore_dowork(struct work_struct *work)
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 1376e5a8f0d..3b5744306ed 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -86,6 +86,7 @@ struct ramoops_context {
struct persistent_ram_ecc_info ecc_info;
unsigned int max_dump_cnt;
unsigned int dump_write_cnt;
+ /* _read_cnt need clear on ramoops_pstore_open */
unsigned int dump_read_cnt;
unsigned int console_read_cnt;
unsigned int ftrace_read_cnt;
@@ -101,6 +102,7 @@ static int ramoops_pstore_open(struct pstore_info *psi)
cxt->dump_read_cnt = 0;
cxt->console_read_cnt = 0;
+ cxt->ftrace_read_cnt = 0;
return 0;
}
@@ -117,13 +119,15 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
return NULL;
prz = przs[i];
+ if (!prz)
+ return NULL;
- if (update) {
- /* Update old/shadowed buffer. */
+ /* Update old/shadowed buffer. */
+ if (update)
persistent_ram_save_old(prz);
- if (!persistent_ram_old_size(prz))
- return NULL;
- }
+
+ if (!persistent_ram_old_size(prz))
+ return NULL;
*typep = type;
*id = i;
@@ -131,9 +135,31 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
return prz;
}
+static void ramoops_read_kmsg_hdr(char *buffer, struct timespec *time,
+ bool *compressed)
+{
+ char data_type;
+
+ if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
+ &time->tv_sec, &time->tv_nsec, &data_type) == 3) {
+ if (data_type == 'C')
+ *compressed = true;
+ else
+ *compressed = false;
+ } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
+ &time->tv_sec, &time->tv_nsec) == 2) {
+ *compressed = false;
+ } else {
+ time->tv_sec = 0;
+ time->tv_nsec = 0;
+ *compressed = false;
+ }
+}
+
static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *time,
- char **buf, struct pstore_info *psi)
+ char **buf, bool *compressed,
+ struct pstore_info *psi)
{
ssize_t size;
ssize_t ecc_notice_size;
@@ -152,10 +178,6 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
if (!prz)
return 0;
- /* TODO(kees): Bogus time for the moment. */
- time->tv_sec = 0;
- time->tv_nsec = 0;
-
size = persistent_ram_old_size(prz);
/* ECC correction notice */
@@ -166,12 +188,14 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
return -ENOMEM;
memcpy(*buf, persistent_ram_old(prz), size);
+ ramoops_read_kmsg_hdr(*buf, time, compressed);
persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1);
return size + ecc_notice_size;
}
-static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
+static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
+ bool compressed)
{
char *hdr;
struct timespec timestamp;
@@ -182,8 +206,9 @@ static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
timestamp.tv_sec = 0;
timestamp.tv_nsec = 0;
}
- hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
- (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000));
+ hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
+ (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000),
+ compressed ? 'C' : 'D');
WARN_ON_ONCE(!hdr);
len = hdr ? strlen(hdr) : 0;
persistent_ram_write(prz, hdr, len);
@@ -195,7 +220,8 @@ static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
static int notrace ramoops_pstore_write_buf(enum pstore_type_id type,
enum kmsg_dump_reason reason,
u64 *id, unsigned int part,
- const char *buf, size_t size,
+ const char *buf,
+ bool compressed, size_t size,
struct pstore_info *psi)
{
struct ramoops_context *cxt = psi->data;
@@ -241,7 +267,7 @@ static int notrace ramoops_pstore_write_buf(enum pstore_type_id type,
prz = cxt->przs[cxt->dump_write_cnt];
- hlen = ramoops_write_kmsg_hdr(prz);
+ hlen = ramoops_write_kmsg_hdr(prz, compressed);
if (size + hlen > prz->buffer_size)
size = prz->buffer_size - hlen;
persistent_ram_write(prz, buf, size);
@@ -294,6 +320,7 @@ static void ramoops_free_przs(struct ramoops_context *cxt)
{
int i;
+ cxt->max_dump_cnt = 0;
if (!cxt->przs)
return;
@@ -324,7 +351,7 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
GFP_KERNEL);
if (!cxt->przs) {
dev_err(dev, "failed to initialize a prz array for dumps\n");
- return -ENOMEM;
+ goto fail_prz;
}
for (i = 0; i < cxt->max_dump_cnt; i++) {
@@ -399,16 +426,13 @@ static int ramoops_probe(struct platform_device *pdev)
goto fail_out;
}
- if (!is_power_of_2(pdata->mem_size))
- pdata->mem_size = rounddown_pow_of_two(pdata->mem_size);
- if (!is_power_of_2(pdata->record_size))
+ if (pdata->record_size && !is_power_of_2(pdata->record_size))
pdata->record_size = rounddown_pow_of_two(pdata->record_size);
- if (!is_power_of_2(pdata->console_size))
+ if (pdata->console_size && !is_power_of_2(pdata->console_size))
pdata->console_size = rounddown_pow_of_two(pdata->console_size);
- if (!is_power_of_2(pdata->ftrace_size))
+ if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))
pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);
- cxt->dump_read_cnt = 0;
cxt->size = pdata->mem_size;
cxt->phys_addr = pdata->mem_address;
cxt->record_size = pdata->record_size;
@@ -485,7 +509,6 @@ fail_buf:
kfree(cxt->pstore.buf);
fail_clear:
cxt->pstore.bufsize = 0;
- cxt->max_dump_cnt = 0;
fail_cnt:
kfree(cxt->fprz);
fail_init_fprz:
diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 59337326e28..34a1e5aa848 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -12,6 +12,8 @@
*
*/
+#define pr_fmt(fmt) "persistent_ram: " fmt
+
#include <linux/device.h>
#include <linux/err.h>
#include <linux/errno.h>
@@ -46,7 +48,7 @@ static inline size_t buffer_start(struct persistent_ram_zone *prz)
}
/* increase and wrap the start pointer, returning the old value */
-static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a)
+static size_t buffer_start_add_atomic(struct persistent_ram_zone *prz, size_t a)
{
int old;
int new;
@@ -54,7 +56,7 @@ static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a)
do {
old = atomic_read(&prz->buffer->start);
new = old + a;
- while (unlikely(new > prz->buffer_size))
+ while (unlikely(new >= prz->buffer_size))
new -= prz->buffer_size;
} while (atomic_cmpxchg(&prz->buffer->start, old, new) != old);
@@ -62,7 +64,7 @@ static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a)
}
/* increase the size counter until it hits the max size */
-static inline void buffer_size_add(struct persistent_ram_zone *prz, size_t a)
+static void buffer_size_add_atomic(struct persistent_ram_zone *prz, size_t a)
{
size_t old;
size_t new;
@@ -78,6 +80,53 @@ static inline void buffer_size_add(struct persistent_ram_zone *prz, size_t a)
} while (atomic_cmpxchg(&prz->buffer->size, old, new) != old);
}
+static DEFINE_RAW_SPINLOCK(buffer_lock);
+
+/* increase and wrap the start pointer, returning the old value */
+static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a)
+{
+ int old;
+ int new;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&buffer_lock, flags);
+
+ old = atomic_read(&prz->buffer->start);
+ new = old + a;
+ while (unlikely(new >= prz->buffer_size))
+ new -= prz->buffer_size;
+ atomic_set(&prz->buffer->start, new);
+
+ raw_spin_unlock_irqrestore(&buffer_lock, flags);
+
+ return old;
+}
+
+/* increase the size counter until it hits the max size */
+static void buffer_size_add_locked(struct persistent_ram_zone *prz, size_t a)
+{
+ size_t old;
+ size_t new;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&buffer_lock, flags);
+
+ old = atomic_read(&prz->buffer->size);
+ if (old == prz->buffer_size)
+ goto exit;
+
+ new = old + a;
+ if (new > prz->buffer_size)
+ new = prz->buffer_size;
+ atomic_set(&prz->buffer->size, new);
+
+exit:
+ raw_spin_unlock_irqrestore(&buffer_lock, flags);
+}
+
+static size_t (*buffer_start_add)(struct persistent_ram_zone *, size_t) = buffer_start_add_atomic;
+static void (*buffer_size_add)(struct persistent_ram_zone *, size_t) = buffer_size_add_atomic;
+
static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz,
uint8_t *data, size_t len, uint8_t *ecc)
{
@@ -158,12 +207,10 @@ static void persistent_ram_ecc_old(struct persistent_ram_zone *prz)
size = buffer->data + prz->buffer_size - block;
numerr = persistent_ram_decode_rs8(prz, block, size, par);
if (numerr > 0) {
- pr_devel("persistent_ram: error in block %p, %d\n",
- block, numerr);
+ pr_devel("error in block %p, %d\n", block, numerr);
prz->corrected_bytes += numerr;
} else if (numerr < 0) {
- pr_devel("persistent_ram: uncorrectable error in block %p\n",
- block);
+ pr_devel("uncorrectable error in block %p\n", block);
prz->bad_blocks++;
}
block += prz->ecc_info.block_size;
@@ -210,7 +257,7 @@ static int persistent_ram_init_ecc(struct persistent_ram_zone *prz,
prz->rs_decoder = init_rs(prz->ecc_info.symsize, prz->ecc_info.poly,
0, 1, prz->ecc_info.ecc_size);
if (prz->rs_decoder == NULL) {
- pr_info("persistent_ram: init_rs failed\n");
+ pr_info("init_rs failed\n");
return -EINVAL;
}
@@ -220,10 +267,10 @@ static int persistent_ram_init_ecc(struct persistent_ram_zone *prz,
numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer),
prz->par_header);
if (numerr > 0) {
- pr_info("persistent_ram: error in header, %d\n", numerr);
+ pr_info("error in header, %d\n", numerr);
prz->corrected_bytes += numerr;
} else if (numerr < 0) {
- pr_info("persistent_ram: uncorrectable error in header\n");
+ pr_info("uncorrectable error in header\n");
prz->bad_blocks++;
}
@@ -270,7 +317,7 @@ void persistent_ram_save_old(struct persistent_ram_zone *prz)
prz->old_log = kmalloc(size, GFP_KERNEL);
}
if (!prz->old_log) {
- pr_err("persistent_ram: failed to allocate buffer\n");
+ pr_err("failed to allocate buffer\n");
return;
}
@@ -349,8 +396,8 @@ static void *persistent_ram_vmap(phys_addr_t start, size_t size)
pages = kmalloc(sizeof(struct page *) * page_count, GFP_KERNEL);
if (!pages) {
- pr_err("%s: Failed to allocate array for %u pages\n", __func__,
- page_count);
+ pr_err("%s: Failed to allocate array for %u pages\n",
+ __func__, page_count);
return NULL;
}
@@ -372,6 +419,9 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size)
return NULL;
}
+ buffer_start_add = buffer_start_add_locked;
+ buffer_size_add = buffer_size_add_locked;
+
return ioremap(start, size);
}
@@ -412,19 +462,17 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig,
if (prz->buffer->sig == sig) {
if (buffer_size(prz) > prz->buffer_size ||
buffer_start(prz) > buffer_size(prz))
- pr_info("persistent_ram: found existing invalid buffer,"
- " size %zu, start %zu\n",
- buffer_size(prz), buffer_start(prz));
+ pr_info("found existing invalid buffer, size %zu, start %zu\n",
+ buffer_size(prz), buffer_start(prz));
else {
- pr_debug("persistent_ram: found existing buffer,"
- " size %zu, start %zu\n",
- buffer_size(prz), buffer_start(prz));
+ 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("persistent_ram: no valid data in buffer"
- " (sig = 0x%08x)\n", prz->buffer->sig);
+ pr_debug("no valid data in buffer (sig = 0x%08x)\n",
+ prz->buffer->sig);
}
prz->buffer->sig = sig;
@@ -459,7 +507,7 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL);
if (!prz) {
- pr_err("persistent_ram: failed to allocate persistent ram zone\n");
+ pr_err("failed to allocate persistent ram zone\n");
goto err;
}