Merge branch 'akpm' (incoming from Andrew)

Merge second patch-bomb from Andrew Morton:
 - the rest of MM
 - zram updates
 - zswap updates
 - exit
 - procfs
 - exec
 - wait
 - crash dump
 - lib/idr
 - rapidio
 - adfs, affs, bfs, ufs
 - cris
 - Kconfig things
 - initramfs
 - small amount of IPC material
 - percpu enhancements
 - early ioremap support
 - various other misc things

* emailed patches from Andrew Morton <[email protected]>: (156 commits)
  MAINTAINERS: update Intel C600 SAS driver maintainers
  fs/ufs: remove unused ufs_super_block_third pointer
  fs/ufs: remove unused ufs_super_block_second pointer
  fs/ufs: remove unused ufs_super_block_first pointer
  fs/ufs/super.c: add __init to init_inodecache()
  doc/kernel-parameters.txt: add early_ioremap_debug
  arm64: add early_ioremap support
  arm64: initialize pgprot info earlier in boot
  x86: use generic early_ioremap
  mm: create generic early_ioremap() support
  x86/mm: sparse warning fix for early_memremap
  lglock: map to spinlock when !CONFIG_SMP
  percpu: add preemption checks to __this_cpu ops
  vmstat: use raw_cpu_ops to avoid false positives on preemption checks
  slub: use raw_cpu_inc for incrementing statistics
  net: replace __this_cpu_inc in route.c with raw_cpu_inc
  modules: use raw_cpu_write for initialization of per cpu refcount.
  mm: use raw_cpu ops for determining current NUMA node
  percpu: add raw_cpu_ops
  slub: fix leak of 'name' in sysfs_slab_add
  ...
This commit is contained in:
Linus Torvalds 2014-04-07 16:38:06 -07:00
commit 26c12d9334
233 changed files with 3714 additions and 2012 deletions

View file

@ -15,6 +15,16 @@ config ZRAM
See zram.txt for more information.
config ZRAM_LZ4_COMPRESS
bool "Enable LZ4 algorithm support"
depends on ZRAM
select LZ4_COMPRESS
select LZ4_DECOMPRESS
default n
help
This option enables LZ4 compression algorithm support. Compression
algorithm can be changed using `comp_algorithm' device attribute.
config ZRAM_DEBUG
bool "Compressed RAM block device debug support"
depends on ZRAM

View file

@ -1,3 +1,5 @@
zram-y := zram_drv.o
zram-y := zcomp_lzo.o zcomp.o zram_drv.o
zram-$(CONFIG_ZRAM_LZ4_COMPRESS) += zcomp_lz4.o
obj-$(CONFIG_ZRAM) += zram.o

353
drivers/block/zram/zcomp.c Normal file
View file

@ -0,0 +1,353 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include "zcomp.h"
#include "zcomp_lzo.h"
#ifdef CONFIG_ZRAM_LZ4_COMPRESS
#include "zcomp_lz4.h"
#endif
/*
* single zcomp_strm backend
*/
struct zcomp_strm_single {
struct mutex strm_lock;
struct zcomp_strm *zstrm;
};
/*
* multi zcomp_strm backend
*/
struct zcomp_strm_multi {
/* protect strm list */
spinlock_t strm_lock;
/* max possible number of zstrm streams */
int max_strm;
/* number of available zstrm streams */
int avail_strm;
/* list of available strms */
struct list_head idle_strm;
wait_queue_head_t strm_wait;
};
static struct zcomp_backend *backends[] = {
&zcomp_lzo,
#ifdef CONFIG_ZRAM_LZ4_COMPRESS
&zcomp_lz4,
#endif
NULL
};
static struct zcomp_backend *find_backend(const char *compress)
{
int i = 0;
while (backends[i]) {
if (sysfs_streq(compress, backends[i]->name))
break;
i++;
}
return backends[i];
}
static void zcomp_strm_free(struct zcomp *comp, struct zcomp_strm *zstrm)
{
if (zstrm->private)
comp->backend->destroy(zstrm->private);
free_pages((unsigned long)zstrm->buffer, 1);
kfree(zstrm);
}
/*
* allocate new zcomp_strm structure with ->private initialized by
* backend, return NULL on error
*/
static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp)
{
struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), GFP_KERNEL);
if (!zstrm)
return NULL;
zstrm->private = comp->backend->create();
/*
* allocate 2 pages. 1 for compressed data, plus 1 extra for the
* case when compressed size is larger than the original one
*/
zstrm->buffer = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
if (!zstrm->private || !zstrm->buffer) {
zcomp_strm_free(comp, zstrm);
zstrm = NULL;
}
return zstrm;
}
/*
* get idle zcomp_strm or wait until other process release
* (zcomp_strm_release()) one for us
*/
static struct zcomp_strm *zcomp_strm_multi_find(struct zcomp *comp)
{
struct zcomp_strm_multi *zs = comp->stream;
struct zcomp_strm *zstrm;
while (1) {
spin_lock(&zs->strm_lock);
if (!list_empty(&zs->idle_strm)) {
zstrm = list_entry(zs->idle_strm.next,
struct zcomp_strm, list);
list_del(&zstrm->list);
spin_unlock(&zs->strm_lock);
return zstrm;
}
/* zstrm streams limit reached, wait for idle stream */
if (zs->avail_strm >= zs->max_strm) {
spin_unlock(&zs->strm_lock);
wait_event(zs->strm_wait, !list_empty(&zs->idle_strm));
continue;
}
/* allocate new zstrm stream */
zs->avail_strm++;
spin_unlock(&zs->strm_lock);
zstrm = zcomp_strm_alloc(comp);
if (!zstrm) {
spin_lock(&zs->strm_lock);
zs->avail_strm--;
spin_unlock(&zs->strm_lock);
wait_event(zs->strm_wait, !list_empty(&zs->idle_strm));
continue;
}
break;
}
return zstrm;
}
/* add stream back to idle list and wake up waiter or free the stream */
static void zcomp_strm_multi_release(struct zcomp *comp, struct zcomp_strm *zstrm)
{
struct zcomp_strm_multi *zs = comp->stream;
spin_lock(&zs->strm_lock);
if (zs->avail_strm <= zs->max_strm) {
list_add(&zstrm->list, &zs->idle_strm);
spin_unlock(&zs->strm_lock);
wake_up(&zs->strm_wait);
return;
}
zs->avail_strm--;
spin_unlock(&zs->strm_lock);
zcomp_strm_free(comp, zstrm);
}
/* change max_strm limit */
static bool zcomp_strm_multi_set_max_streams(struct zcomp *comp, int num_strm)
{
struct zcomp_strm_multi *zs = comp->stream;
struct zcomp_strm *zstrm;
spin_lock(&zs->strm_lock);
zs->max_strm = num_strm;
/*
* if user has lowered the limit and there are idle streams,
* immediately free as much streams (and memory) as we can.
*/
while (zs->avail_strm > num_strm && !list_empty(&zs->idle_strm)) {
zstrm = list_entry(zs->idle_strm.next,
struct zcomp_strm, list);
list_del(&zstrm->list);
zcomp_strm_free(comp, zstrm);
zs->avail_strm--;
}
spin_unlock(&zs->strm_lock);
return true;
}
static void zcomp_strm_multi_destroy(struct zcomp *comp)
{
struct zcomp_strm_multi *zs = comp->stream;
struct zcomp_strm *zstrm;
while (!list_empty(&zs->idle_strm)) {
zstrm = list_entry(zs->idle_strm.next,
struct zcomp_strm, list);
list_del(&zstrm->list);
zcomp_strm_free(comp, zstrm);
}
kfree(zs);
}
static int zcomp_strm_multi_create(struct zcomp *comp, int max_strm)
{
struct zcomp_strm *zstrm;
struct zcomp_strm_multi *zs;
comp->destroy = zcomp_strm_multi_destroy;
comp->strm_find = zcomp_strm_multi_find;
comp->strm_release = zcomp_strm_multi_release;
comp->set_max_streams = zcomp_strm_multi_set_max_streams;
zs = kmalloc(sizeof(struct zcomp_strm_multi), GFP_KERNEL);
if (!zs)
return -ENOMEM;
comp->stream = zs;
spin_lock_init(&zs->strm_lock);
INIT_LIST_HEAD(&zs->idle_strm);
init_waitqueue_head(&zs->strm_wait);
zs->max_strm = max_strm;
zs->avail_strm = 1;
zstrm = zcomp_strm_alloc(comp);
if (!zstrm) {
kfree(zs);
return -ENOMEM;
}
list_add(&zstrm->list, &zs->idle_strm);
return 0;
}
static struct zcomp_strm *zcomp_strm_single_find(struct zcomp *comp)
{
struct zcomp_strm_single *zs = comp->stream;
mutex_lock(&zs->strm_lock);
return zs->zstrm;
}
static void zcomp_strm_single_release(struct zcomp *comp,
struct zcomp_strm *zstrm)
{
struct zcomp_strm_single *zs = comp->stream;
mutex_unlock(&zs->strm_lock);
}
static bool zcomp_strm_single_set_max_streams(struct zcomp *comp, int num_strm)
{
/* zcomp_strm_single support only max_comp_streams == 1 */
return false;
}
static void zcomp_strm_single_destroy(struct zcomp *comp)
{
struct zcomp_strm_single *zs = comp->stream;
zcomp_strm_free(comp, zs->zstrm);
kfree(zs);
}
static int zcomp_strm_single_create(struct zcomp *comp)
{
struct zcomp_strm_single *zs;
comp->destroy = zcomp_strm_single_destroy;
comp->strm_find = zcomp_strm_single_find;
comp->strm_release = zcomp_strm_single_release;
comp->set_max_streams = zcomp_strm_single_set_max_streams;
zs = kmalloc(sizeof(struct zcomp_strm_single), GFP_KERNEL);
if (!zs)
return -ENOMEM;
comp->stream = zs;
mutex_init(&zs->strm_lock);
zs->zstrm = zcomp_strm_alloc(comp);
if (!zs->zstrm) {
kfree(zs);
return -ENOMEM;
}
return 0;
}
/* show available compressors */
ssize_t zcomp_available_show(const char *comp, char *buf)
{
ssize_t sz = 0;
int i = 0;
while (backends[i]) {
if (sysfs_streq(comp, backends[i]->name))
sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
"[%s] ", backends[i]->name);
else
sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
"%s ", backends[i]->name);
i++;
}
sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
return sz;
}
bool zcomp_set_max_streams(struct zcomp *comp, int num_strm)
{
return comp->set_max_streams(comp, num_strm);
}
struct zcomp_strm *zcomp_strm_find(struct zcomp *comp)
{
return comp->strm_find(comp);
}
void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm)
{
comp->strm_release(comp, zstrm);
}
int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
const unsigned char *src, size_t *dst_len)
{
return comp->backend->compress(src, zstrm->buffer, dst_len,
zstrm->private);
}
int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
size_t src_len, unsigned char *dst)
{
return comp->backend->decompress(src, src_len, dst);
}
void zcomp_destroy(struct zcomp *comp)
{
comp->destroy(comp);
kfree(comp);
}
/*
* search available compressors for requested algorithm.
* allocate new zcomp and initialize it. return compressing
* backend pointer or ERR_PTR if things went bad. ERR_PTR(-EINVAL)
* if requested algorithm is not supported, ERR_PTR(-ENOMEM) in
* case of allocation error.
*/
struct zcomp *zcomp_create(const char *compress, int max_strm)
{
struct zcomp *comp;
struct zcomp_backend *backend;
backend = find_backend(compress);
if (!backend)
return ERR_PTR(-EINVAL);
comp = kzalloc(sizeof(struct zcomp), GFP_KERNEL);
if (!comp)
return ERR_PTR(-ENOMEM);
comp->backend = backend;
if (max_strm > 1)
zcomp_strm_multi_create(comp, max_strm);
else
zcomp_strm_single_create(comp);
if (!comp->stream) {
kfree(comp);
return ERR_PTR(-ENOMEM);
}
return comp;
}

View file

@ -0,0 +1,68 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ZCOMP_H_
#define _ZCOMP_H_
#include <linux/mutex.h>
struct zcomp_strm {
/* compression/decompression buffer */
void *buffer;
/*
* The private data of the compression stream, only compression
* stream backend can touch this (e.g. compression algorithm
* working memory)
*/
void *private;
/* used in multi stream backend, protected by backend strm_lock */
struct list_head list;
};
/* static compression backend */
struct zcomp_backend {
int (*compress)(const unsigned char *src, unsigned char *dst,
size_t *dst_len, void *private);
int (*decompress)(const unsigned char *src, size_t src_len,
unsigned char *dst);
void *(*create)(void);
void (*destroy)(void *private);
const char *name;
};
/* dynamic per-device compression frontend */
struct zcomp {
void *stream;
struct zcomp_backend *backend;
struct zcomp_strm *(*strm_find)(struct zcomp *comp);
void (*strm_release)(struct zcomp *comp, struct zcomp_strm *zstrm);
bool (*set_max_streams)(struct zcomp *comp, int num_strm);
void (*destroy)(struct zcomp *comp);
};
ssize_t zcomp_available_show(const char *comp, char *buf);
struct zcomp *zcomp_create(const char *comp, int max_strm);
void zcomp_destroy(struct zcomp *comp);
struct zcomp_strm *zcomp_strm_find(struct zcomp *comp);
void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm);
int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
const unsigned char *src, size_t *dst_len);
int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
size_t src_len, unsigned char *dst);
bool zcomp_set_max_streams(struct zcomp *comp, int num_strm);
#endif /* _ZCOMP_H_ */

View file

@ -0,0 +1,47 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/lz4.h>
#include "zcomp_lz4.h"
static void *zcomp_lz4_create(void)
{
return kzalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);
}
static void zcomp_lz4_destroy(void *private)
{
kfree(private);
}
static int zcomp_lz4_compress(const unsigned char *src, unsigned char *dst,
size_t *dst_len, void *private)
{
/* return : Success if return 0 */
return lz4_compress(src, PAGE_SIZE, dst, dst_len, private);
}
static int zcomp_lz4_decompress(const unsigned char *src, size_t src_len,
unsigned char *dst)
{
size_t dst_len = PAGE_SIZE;
/* return : Success if return 0 */
return lz4_decompress_unknownoutputsize(src, src_len, dst, &dst_len);
}
struct zcomp_backend zcomp_lz4 = {
.compress = zcomp_lz4_compress,
.decompress = zcomp_lz4_decompress,
.create = zcomp_lz4_create,
.destroy = zcomp_lz4_destroy,
.name = "lz4",
};

View file

@ -0,0 +1,17 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ZCOMP_LZ4_H_
#define _ZCOMP_LZ4_H_
#include "zcomp.h"
extern struct zcomp_backend zcomp_lz4;
#endif /* _ZCOMP_LZ4_H_ */

View file

@ -0,0 +1,47 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/lzo.h>
#include "zcomp_lzo.h"
static void *lzo_create(void)
{
return kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
}
static void lzo_destroy(void *private)
{
kfree(private);
}
static int lzo_compress(const unsigned char *src, unsigned char *dst,
size_t *dst_len, void *private)
{
int ret = lzo1x_1_compress(src, PAGE_SIZE, dst, dst_len, private);
return ret == LZO_E_OK ? 0 : ret;
}
static int lzo_decompress(const unsigned char *src, size_t src_len,
unsigned char *dst)
{
size_t dst_len = PAGE_SIZE;
int ret = lzo1x_decompress_safe(src, src_len, dst, &dst_len);
return ret == LZO_E_OK ? 0 : ret;
}
struct zcomp_backend zcomp_lzo = {
.compress = lzo_compress,
.decompress = lzo_decompress,
.create = lzo_create,
.destroy = lzo_destroy,
.name = "lzo",
};

View file

@ -0,0 +1,17 @@
/*
* Copyright (C) 2014 Sergey Senozhatsky.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ZCOMP_LZO_H_
#define _ZCOMP_LZO_H_
#include "zcomp.h"
extern struct zcomp_backend zcomp_lzo;
#endif /* _ZCOMP_LZO_H_ */

View file

@ -29,19 +29,36 @@
#include <linux/genhd.h>
#include <linux/highmem.h>
#include <linux/slab.h>
#include <linux/lzo.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/err.h>
#include "zram_drv.h"
/* Globals */
static int zram_major;
static struct zram *zram_devices;
static const char *default_compressor = "lzo";
/* Module params (documentation at end) */
static unsigned int num_devices = 1;
#define ZRAM_ATTR_RO(name) \
static ssize_t zram_attr_##name##_show(struct device *d, \
struct device_attribute *attr, char *b) \
{ \
struct zram *zram = dev_to_zram(d); \
return scnprintf(b, PAGE_SIZE, "%llu\n", \
(u64)atomic64_read(&zram->stats.name)); \
} \
static struct device_attribute dev_attr_##name = \
__ATTR(name, S_IRUGO, zram_attr_##name##_show, NULL);
static inline int init_done(struct zram *zram)
{
return zram->meta != NULL;
}
static inline struct zram *dev_to_zram(struct device *dev)
{
return (struct zram *)dev_to_disk(dev)->private_data;
@ -52,59 +69,20 @@ static ssize_t disksize_show(struct device *dev,
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n", zram->disksize);
return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize);
}
static ssize_t initstate_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
u32 val;
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%u\n", zram->init_done);
}
down_read(&zram->init_lock);
val = init_done(zram);
up_read(&zram->init_lock);
static ssize_t num_reads_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)atomic64_read(&zram->stats.num_reads));
}
static ssize_t num_writes_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)atomic64_read(&zram->stats.num_writes));
}
static ssize_t invalid_io_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)atomic64_read(&zram->stats.invalid_io));
}
static ssize_t notify_free_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)atomic64_read(&zram->stats.notify_free));
}
static ssize_t zero_pages_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%u\n", atomic_read(&zram->stats.pages_zero));
return scnprintf(buf, PAGE_SIZE, "%u\n", val);
}
static ssize_t orig_data_size_show(struct device *dev,
@ -112,17 +90,8 @@ static ssize_t orig_data_size_show(struct device *dev,
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)(atomic_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
}
static ssize_t compr_data_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
return sprintf(buf, "%llu\n",
(u64)atomic64_read(&zram->stats.compr_size));
return scnprintf(buf, PAGE_SIZE, "%llu\n",
(u64)(atomic64_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
}
static ssize_t mem_used_total_show(struct device *dev,
@ -133,11 +102,81 @@ static ssize_t mem_used_total_show(struct device *dev,
struct zram_meta *meta = zram->meta;
down_read(&zram->init_lock);
if (zram->init_done)
if (init_done(zram))
val = zs_get_total_size_bytes(meta->mem_pool);
up_read(&zram->init_lock);
return sprintf(buf, "%llu\n", val);
return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
}
static ssize_t max_comp_streams_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
int val;
struct zram *zram = dev_to_zram(dev);
down_read(&zram->init_lock);
val = zram->max_comp_streams;
up_read(&zram->init_lock);
return scnprintf(buf, PAGE_SIZE, "%d\n", val);
}
static ssize_t max_comp_streams_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
int num;
struct zram *zram = dev_to_zram(dev);
int ret;
ret = kstrtoint(buf, 0, &num);
if (ret < 0)
return ret;
if (num < 1)
return -EINVAL;
down_write(&zram->init_lock);
if (init_done(zram)) {
if (!zcomp_set_max_streams(zram->comp, num)) {
pr_info("Cannot change max compression streams\n");
ret = -EINVAL;
goto out;
}
}
zram->max_comp_streams = num;
ret = len;
out:
up_write(&zram->init_lock);
return ret;
}
static ssize_t comp_algorithm_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
size_t sz;
struct zram *zram = dev_to_zram(dev);
down_read(&zram->init_lock);
sz = zcomp_available_show(zram->compressor, buf);
up_read(&zram->init_lock);
return sz;
}
static ssize_t comp_algorithm_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
struct zram *zram = dev_to_zram(dev);
down_write(&zram->init_lock);
if (init_done(zram)) {
up_write(&zram->init_lock);
pr_info("Can't change algorithm for initialized device\n");
return -EBUSY;
}
strlcpy(zram->compressor, buf, sizeof(zram->compressor));
up_write(&zram->init_lock);
return len;
}
/* flag operations needs meta->tb_lock */
@ -192,8 +231,6 @@ static inline int valid_io_request(struct zram *zram, struct bio *bio)
static void zram_meta_free(struct zram_meta *meta)
{
zs_destroy_pool(meta->mem_pool);
kfree(meta->compress_workmem);
free_pages((unsigned long)meta->compress_buffer, 1);
vfree(meta->table);
kfree(meta);
}
@ -205,22 +242,11 @@ static struct zram_meta *zram_meta_alloc(u64 disksize)
if (!meta)
goto out;
meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
if (!meta->compress_workmem)
goto free_meta;
meta->compress_buffer =
(void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
if (!meta->compress_buffer) {
pr_err("Error allocating compressor buffer space\n");
goto free_workmem;
}
num_pages = disksize >> PAGE_SHIFT;
meta->table = vzalloc(num_pages * sizeof(*meta->table));
if (!meta->table) {
pr_err("Error allocating zram address table\n");
goto free_buffer;
goto free_meta;
}
meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM);
@ -230,15 +256,10 @@ static struct zram_meta *zram_meta_alloc(u64 disksize)
}
rwlock_init(&meta->tb_lock);
mutex_init(&meta->buffer_lock);
return meta;
free_table:
vfree(meta->table);
free_buffer:
free_pages((unsigned long)meta->compress_buffer, 1);
free_workmem:
kfree(meta->compress_workmem);
free_meta:
kfree(meta);
meta = NULL;
@ -288,7 +309,6 @@ static void zram_free_page(struct zram *zram, size_t index)
{
struct zram_meta *meta = zram->meta;
unsigned long handle = meta->table[index].handle;
u16 size = meta->table[index].size;
if (unlikely(!handle)) {
/*
@ -297,21 +317,15 @@ static void zram_free_page(struct zram *zram, size_t index)
*/
if (zram_test_flag(meta, index, ZRAM_ZERO)) {
zram_clear_flag(meta, index, ZRAM_ZERO);
atomic_dec(&zram->stats.pages_zero);
atomic64_dec(&zram->stats.zero_pages);
}
return;
}
if (unlikely(size > max_zpage_size))
atomic_dec(&zram->stats.bad_compress);
zs_free(meta->mem_pool, handle);
if (size <= PAGE_SIZE / 2)
atomic_dec(&zram->stats.good_compress);
atomic64_sub(meta->table[index].size, &zram->stats.compr_size);
atomic_dec(&zram->stats.pages_stored);
atomic64_sub(meta->table[index].size, &zram->stats.compr_data_size);
atomic64_dec(&zram->stats.pages_stored);
meta->table[index].handle = 0;
meta->table[index].size = 0;
@ -319,8 +333,7 @@ static void zram_free_page(struct zram *zram, size_t index)
static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
{
int ret = LZO_E_OK;
size_t clen = PAGE_SIZE;
int ret = 0;
unsigned char *cmem;
struct zram_meta *meta = zram->meta;
unsigned long handle;
@ -340,12 +353,12 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
if (size == PAGE_SIZE)
copy_page(mem, cmem);
else
ret = lzo1x_decompress_safe(cmem, size, mem, &clen);
ret = zcomp_decompress(zram->comp, cmem, size, mem);
zs_unmap_object(meta->mem_pool, handle);
read_unlock(&meta->tb_lock);
/* Should NEVER happen. Return bio error if it does. */
if (unlikely(ret != LZO_E_OK)) {
if (unlikely(ret)) {
pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
atomic64_inc(&zram->stats.failed_reads);
return ret;
@ -388,7 +401,7 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
ret = zram_decompress_page(zram, uncmem, index);
/* Should NEVER happen. Return bio error if it does. */
if (unlikely(ret != LZO_E_OK))
if (unlikely(ret))
goto out_cleanup;
if (is_partial_io(bvec))
@ -413,11 +426,10 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
struct page *page;
unsigned char *user_mem, *cmem, *src, *uncmem = NULL;
struct zram_meta *meta = zram->meta;
struct zcomp_strm *zstrm;
bool locked = false;
page = bvec->bv_page;
src = meta->compress_buffer;
if (is_partial_io(bvec)) {
/*
* This is a partial IO. We need to read the full page
@ -433,7 +445,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
goto out;
}
mutex_lock(&meta->buffer_lock);
zstrm = zcomp_strm_find(zram->comp);
locked = true;
user_mem = kmap_atomic(page);
@ -454,28 +466,25 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
zram_set_flag(meta, index, ZRAM_ZERO);
write_unlock(&zram->meta->tb_lock);
atomic_inc(&zram->stats.pages_zero);
atomic64_inc(&zram->stats.zero_pages);
ret = 0;
goto out;
}
ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen,
meta->compress_workmem);
ret = zcomp_compress(zram->comp, zstrm, uncmem, &clen);
if (!is_partial_io(bvec)) {
kunmap_atomic(user_mem);
user_mem = NULL;
uncmem = NULL;
}
if (unlikely(ret != LZO_E_OK)) {
if (unlikely(ret)) {
pr_err("Compression failed! err=%d\n", ret);
goto out;
}
src = zstrm->buffer;
if (unlikely(clen > max_zpage_size)) {
atomic_inc(&zram->stats.bad_compress);
clen = PAGE_SIZE;
src = NULL;
if (is_partial_io(bvec))
src = uncmem;
}
@ -497,6 +506,8 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
memcpy(cmem, src, clen);
}
zcomp_strm_release(zram->comp, zstrm);
locked = false;
zs_unmap_object(meta->mem_pool, handle);
/*
@ -511,49 +522,88 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
write_unlock(&zram->meta->tb_lock);
/* Update stats */
atomic64_add(clen, &zram->stats.compr_size);
atomic_inc(&zram->stats.pages_stored);
if (clen <= PAGE_SIZE / 2)
atomic_inc(&zram->stats.good_compress);
atomic64_add(clen, &zram->stats.compr_data_size);
atomic64_inc(&zram->stats.pages_stored);
out:
if (locked)
mutex_unlock(&meta->buffer_lock);
zcomp_strm_release(zram->comp, zstrm);
if (is_partial_io(bvec))
kfree(uncmem);
if (ret)
atomic64_inc(&zram->stats.failed_writes);
return ret;
}
static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
int offset, struct bio *bio, int rw)
int offset, struct bio *bio)
{
int ret;
int rw = bio_data_dir(bio);
if (rw == READ)
if (rw == READ) {
atomic64_inc(&zram->stats.num_reads);
ret = zram_bvec_read(zram, bvec, index, offset, bio);
else
} else {
atomic64_inc(&zram->stats.num_writes);
ret = zram_bvec_write(zram, bvec, index, offset);
}
return ret;
}
/*
* zram_bio_discard - handler on discard request
* @index: physical block index in PAGE_SIZE units
* @offset: byte offset within physical block
*/
static void zram_bio_discard(struct zram *zram, u32 index,
int offset, struct bio *bio)
{
size_t n = bio->bi_iter.bi_size;
/*
* zram manages data in physical block size units. Because logical block
* size isn't identical with physical block size on some arch, we
* could get a discard request pointing to a specific offset within a
* certain physical block. Although we can handle this request by
* reading that physiclal block and decompressing and partially zeroing
* and re-compressing and then re-storing it, this isn't reasonable
* because our intent with a discard request is to save memory. So
* skipping this logical block is appropriate here.
*/
if (offset) {
if (n < offset)
return;
n -= offset;
index++;
}
while (n >= PAGE_SIZE) {
/*
* Discard request can be large so the lock hold times could be
* lengthy. So take the lock once per page.
*/
write_lock(&zram->meta->tb_lock);
zram_free_page(zram, index);
write_unlock(&zram->meta->tb_lock);
index++;
n -= PAGE_SIZE;
}
}
static void zram_reset_device(struct zram *zram, bool reset_capacity)
{
size_t index;
struct zram_meta *meta;
down_write(&zram->init_lock);
if (!zram->init_done) {
if (!init_done(zram)) {
up_write(&zram->init_lock);
return;
}
meta = zram->meta;
zram->init_done = 0;
/* Free all pages that are still in this zram device */
for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
unsigned long handle = meta->table[index].handle;
@ -563,6 +613,9 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity)
zs_free(meta->mem_pool, handle);
}
zcomp_destroy(zram->comp);
zram->max_comp_streams = 1;
zram_meta_free(zram->meta);
zram->meta = NULL;
/* Reset stats */
@ -574,37 +627,14 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity)
up_write(&zram->init_lock);
}
static void zram_init_device(struct zram *zram, struct zram_meta *meta)
{
if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) {
pr_info(
"There is little point creating a zram of greater than "
"twice the size of memory since we expect a 2:1 compression "
"ratio. Note that zram uses about 0.1%% of the size of "
"the disk when not in use so a huge zram is "
"wasteful.\n"
"\tMemory Size: %lu kB\n"
"\tSize you selected: %llu kB\n"
"Continuing anyway ...\n",
(totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10
);
}
/* zram devices sort of resembles non-rotational disks */
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
zram->meta = meta;
zram->init_done = 1;
pr_debug("Initialization done!\n");
}
static ssize_t disksize_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
u64 disksize;
struct zcomp *comp;
struct zram_meta *meta;
struct zram *zram = dev_to_zram(dev);
int err;
disksize = memparse(buf, NULL);
if (!disksize)
@ -614,20 +644,35 @@ static ssize_t disksize_store(struct device *dev,
meta = zram_meta_alloc(disksize);
if (!meta)
return -ENOMEM;
down_write(&zram->init_lock);
if (zram->init_done) {
up_write(&zram->init_lock);
zram_meta_free(meta);
pr_info("Cannot change disksize for initialized device\n");
return -EBUSY;
comp = zcomp_create(zram->compressor, zram->max_comp_streams);
if (IS_ERR(comp)) {
pr_info("Cannot initialise %s compressing backend\n",
zram->compressor);
err = PTR_ERR(comp);
goto out_free_meta;
}
down_write(&zram->init_lock);
if (init_done(zram)) {
pr_info("Cannot change disksize for initialized device\n");
err = -EBUSY;
goto out_destroy_comp;
}
zram->meta = meta;
zram->comp = comp;
zram->disksize = disksize;
set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
zram_init_device(zram, meta);
up_write(&zram->init_lock);
return len;
out_destroy_comp:
up_write(&zram->init_lock);
zcomp_destroy(comp);
out_free_meta:
zram_meta_free(meta);
return err;
}
static ssize_t reset_store(struct device *dev,
@ -671,26 +716,23 @@ out:
return ret;
}
static void __zram_make_request(struct zram *zram, struct bio *bio, int rw)
static void __zram_make_request(struct zram *zram, struct bio *bio)
{
int offset;
u32 index;
struct bio_vec bvec;
struct bvec_iter iter;
switch (rw) {
case READ:
atomic64_inc(&zram->stats.num_reads);
break;
case WRITE:
atomic64_inc(&zram->stats.num_writes);
break;
}
index = bio->bi_iter.bi_sector >> SECTORS_PER_PAGE_SHIFT;
offset = (bio->bi_iter.bi_sector &
(SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT;
if (unlikely(bio->bi_rw & REQ_DISCARD)) {
zram_bio_discard(zram, index, offset, bio);
bio_endio(bio, 0);
return;
}
bio_for_each_segment(bvec, bio, iter) {
int max_transfer_size = PAGE_SIZE - offset;
@ -705,16 +747,15 @@ static void __zram_make_request(struct zram *zram, struct bio *bio, int rw)
bv.bv_len = max_transfer_size;
bv.bv_offset = bvec.bv_offset;
if (zram_bvec_rw(zram, &bv, index, offset, bio, rw) < 0)
if (zram_bvec_rw(zram, &bv, index, offset, bio) < 0)
goto out;
bv.bv_len = bvec.bv_len - max_transfer_size;
bv.bv_offset += max_transfer_size;
if (zram_bvec_rw(zram, &bv, index+1, 0, bio, rw) < 0)
if (zram_bvec_rw(zram, &bv, index + 1, 0, bio) < 0)
goto out;
} else
if (zram_bvec_rw(zram, &bvec, index, offset, bio, rw)
< 0)
if (zram_bvec_rw(zram, &bvec, index, offset, bio) < 0)
goto out;
update_position(&index, &offset, &bvec);
@ -736,7 +777,7 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
struct zram *zram = queue->queuedata;
down_read(&zram->init_lock);
if (unlikely(!zram->init_done))
if (unlikely(!init_done(zram)))
goto error;
if (!valid_io_request(zram, bio)) {
@ -744,7 +785,7 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
goto error;
}
__zram_make_request(zram, bio, bio_data_dir(bio));
__zram_make_request(zram, bio);
up_read(&zram->init_lock);
return;
@ -778,14 +819,21 @@ static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR,
disksize_show, disksize_store);
static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL);
static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store);
static DEVICE_ATTR(num_reads, S_IRUGO, num_reads_show, NULL);
static DEVICE_ATTR(num_writes, S_IRUGO, num_writes_show, NULL);
static DEVICE_ATTR(invalid_io, S_IRUGO, invalid_io_show, NULL);
static DEVICE_ATTR(notify_free, S_IRUGO, notify_free_show, NULL);
static DEVICE_ATTR(zero_pages, S_IRUGO, zero_pages_show, NULL);
static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL);
static DEVICE_ATTR(compr_data_size, S_IRUGO, compr_data_size_show, NULL);
static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL);
static DEVICE_ATTR(max_comp_streams, S_IRUGO | S_IWUSR,
max_comp_streams_show, max_comp_streams_store);
static DEVICE_ATTR(comp_algorithm, S_IRUGO | S_IWUSR,
comp_algorithm_show, comp_algorithm_store);
ZRAM_ATTR_RO(num_reads);
ZRAM_ATTR_RO(num_writes);
ZRAM_ATTR_RO(failed_reads);
ZRAM_ATTR_RO(failed_writes);
ZRAM_ATTR_RO(invalid_io);
ZRAM_ATTR_RO(notify_free);
ZRAM_ATTR_RO(zero_pages);
ZRAM_ATTR_RO(compr_data_size);
static struct attribute *zram_disk_attrs[] = {
&dev_attr_disksize.attr,
@ -793,12 +841,16 @@ static struct attribute *zram_disk_attrs[] = {
&dev_attr_reset.attr,
&dev_attr_num_reads.attr,
&dev_attr_num_writes.attr,
&dev_attr_failed_reads.attr,
&dev_attr_failed_writes.attr,
&dev_attr_invalid_io.attr,
&dev_attr_notify_free.attr,
&dev_attr_zero_pages.attr,
&dev_attr_orig_data_size.attr,
&dev_attr_compr_data_size.attr,
&dev_attr_mem_used_total.attr,
&dev_attr_max_comp_streams.attr,
&dev_attr_comp_algorithm.attr,
NULL,
};
@ -839,7 +891,8 @@ static int create_device(struct zram *zram, int device_id)
/* Actual capacity set using syfs (/sys/block/zram<id>/disksize */
set_capacity(zram->disk, 0);
/* zram devices sort of resembles non-rotational disks */
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
/*
* To ensure that we always get PAGE_SIZE aligned
* and n*PAGE_SIZED sized I/O requests.
@ -849,6 +902,21 @@ static int create_device(struct zram *zram, int device_id)
ZRAM_LOGICAL_BLOCK_SIZE);
blk_queue_io_min(zram->disk->queue, PAGE_SIZE);
blk_queue_io_opt(zram->disk->queue, PAGE_SIZE);
zram->disk->queue->limits.discard_granularity = PAGE_SIZE;
zram->disk->queue->limits.max_discard_sectors = UINT_MAX;
/*
* zram_bio_discard() will clear all logical blocks if logical block
* size is identical with physical block size(PAGE_SIZE). But if it is
* different, we will skip discarding some parts of logical blocks in
* the part of the request range which isn't aligned to physical block
* size. So we can't ensure that all discarded logical blocks are
* zeroed.
*/
if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE)
zram->disk->queue->limits.discard_zeroes_data = 1;
else
zram->disk->queue->limits.discard_zeroes_data = 0;
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zram->disk->queue);
add_disk(zram->disk);
@ -858,8 +926,9 @@ static int create_device(struct zram *zram, int device_id)
pr_warn("Error creating sysfs group");
goto out_free_disk;
}
zram->init_done = 0;
strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));
zram->meta = NULL;
zram->max_comp_streams = 1;
return 0;
out_free_disk:

View file

@ -16,9 +16,10 @@
#define _ZRAM_DRV_H_
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/zsmalloc.h>
#include "zcomp.h"
/*
* Some arbitrary value. This is just to catch
* invalid value for num_devices module parameter.
@ -64,38 +65,33 @@ enum zram_pageflags {
struct table {
unsigned long handle;
u16 size; /* object size (excluding header) */
u8 count; /* object ref count (not yet used) */
u8 flags;
} __aligned(4);
struct zram_stats {
atomic64_t compr_size; /* compressed size of pages stored */
atomic64_t compr_data_size; /* compressed size of pages stored */
atomic64_t num_reads; /* failed + successful */
atomic64_t num_writes; /* --do-- */
atomic64_t failed_reads; /* should NEVER! happen */
atomic64_t failed_writes; /* can happen when memory is too low */
atomic64_t invalid_io; /* non-page-aligned I/O requests */
atomic64_t notify_free; /* no. of swap slot free notifications */
atomic_t pages_zero; /* no. of zero filled pages */
atomic_t pages_stored; /* no. of pages currently stored */
atomic_t good_compress; /* % of pages with compression ratio<=50% */
atomic_t bad_compress; /* % of pages with compression ratio>=75% */
atomic64_t zero_pages; /* no. of zero filled pages */
atomic64_t pages_stored; /* no. of pages currently stored */
};
struct zram_meta {
rwlock_t tb_lock; /* protect table */
void *compress_workmem;
void *compress_buffer;
struct table *table;
struct zs_pool *mem_pool;
struct mutex buffer_lock; /* protect compress buffers */
};
struct zram {
struct zram_meta *meta;
struct request_queue *queue;
struct gendisk *disk;
int init_done;
struct zcomp *comp;
/* Prevent concurrent execution of device init, reset and R/W request */
struct rw_semaphore init_lock;
/*
@ -103,7 +99,8 @@ struct zram {
* we can store in a disk.
*/
u64 disksize; /* bytes */
int max_comp_streams;
struct zram_stats stats;
char compressor[10];
};
#endif