diff options
Diffstat (limited to 'drivers/block/zram/zram_drv.c')
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 90 |
1 files changed, 66 insertions, 24 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 33c5cc879f24..04ca65912638 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -316,11 +316,9 @@ static ssize_t idle_store(struct device *dev, * See the comment in writeback_store. */ zram_slot_lock(zram, index); - if (!zram_allocated(zram, index) || - zram_test_flag(zram, index, ZRAM_UNDER_WB)) - goto next; - zram_set_flag(zram, index, ZRAM_IDLE); -next: + if (zram_allocated(zram, index) && + !zram_test_flag(zram, index, ZRAM_UNDER_WB)) + zram_set_flag(zram, index, ZRAM_IDLE); zram_slot_unlock(zram, index); } @@ -330,6 +328,41 @@ next: } #ifdef CONFIG_ZRAM_WRITEBACK +static ssize_t writeback_limit_enable_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct zram *zram = dev_to_zram(dev); + u64 val; + ssize_t ret = -EINVAL; + + if (kstrtoull(buf, 10, &val)) + return ret; + + down_read(&zram->init_lock); + spin_lock(&zram->wb_limit_lock); + zram->wb_limit_enable = val; + spin_unlock(&zram->wb_limit_lock); + up_read(&zram->init_lock); + ret = len; + + return ret; +} + +static ssize_t writeback_limit_enable_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + bool val; + struct zram *zram = dev_to_zram(dev); + + down_read(&zram->init_lock); + spin_lock(&zram->wb_limit_lock); + val = zram->wb_limit_enable; + spin_unlock(&zram->wb_limit_lock); + up_read(&zram->init_lock); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} + static ssize_t writeback_limit_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -341,9 +374,9 @@ static ssize_t writeback_limit_store(struct device *dev, return ret; down_read(&zram->init_lock); - atomic64_set(&zram->stats.bd_wb_limit, val); - if (val == 0) - zram->stop_writeback = false; + spin_lock(&zram->wb_limit_lock); + zram->bd_wb_limit = val; + spin_unlock(&zram->wb_limit_lock); up_read(&zram->init_lock); ret = len; @@ -357,7 +390,9 @@ static ssize_t writeback_limit_show(struct device *dev, struct zram *zram = dev_to_zram(dev); down_read(&zram->init_lock); - val = atomic64_read(&zram->stats.bd_wb_limit); + spin_lock(&zram->wb_limit_lock); + val = zram->bd_wb_limit; + spin_unlock(&zram->wb_limit_lock); up_read(&zram->init_lock); return scnprintf(buf, PAGE_SIZE, "%llu\n", val); @@ -588,8 +623,8 @@ static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec, return 1; } -#define HUGE_WRITEBACK 0x1 -#define IDLE_WRITEBACK 0x2 +#define HUGE_WRITEBACK 1 +#define IDLE_WRITEBACK 2 static ssize_t writeback_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) @@ -602,7 +637,7 @@ static ssize_t writeback_store(struct device *dev, struct page *page; ssize_t ret, sz; char mode_buf[8]; - unsigned long mode = -1UL; + int mode = -1; unsigned long blk_idx = 0; sz = strscpy(mode_buf, buf, sizeof(mode_buf)); @@ -618,7 +653,7 @@ static ssize_t writeback_store(struct device *dev, else if (!strcmp(mode_buf, "huge")) mode = HUGE_WRITEBACK; - if (mode == -1UL) + if (mode == -1) return -EINVAL; down_read(&zram->init_lock); @@ -645,10 +680,13 @@ static ssize_t writeback_store(struct device *dev, bvec.bv_len = PAGE_SIZE; bvec.bv_offset = 0; - if (zram->stop_writeback) { + spin_lock(&zram->wb_limit_lock); + if (zram->wb_limit_enable && !zram->bd_wb_limit) { + spin_unlock(&zram->wb_limit_lock); ret = -EIO; break; } + spin_unlock(&zram->wb_limit_lock); if (!blk_idx) { blk_idx = alloc_block_bdev(zram); @@ -667,10 +705,11 @@ static ssize_t writeback_store(struct device *dev, zram_test_flag(zram, index, ZRAM_UNDER_WB)) goto next; - if ((mode & IDLE_WRITEBACK && - !zram_test_flag(zram, index, ZRAM_IDLE)) && - (mode & HUGE_WRITEBACK && - !zram_test_flag(zram, index, ZRAM_HUGE))) + if (mode == IDLE_WRITEBACK && + !zram_test_flag(zram, index, ZRAM_IDLE)) + goto next; + if (mode == HUGE_WRITEBACK && + !zram_test_flag(zram, index, ZRAM_HUGE)) goto next; /* * Clearing ZRAM_UNDER_WB is duty of caller. @@ -732,11 +771,10 @@ static ssize_t writeback_store(struct device *dev, zram_set_element(zram, index, blk_idx); blk_idx = 0; atomic64_inc(&zram->stats.pages_stored); - if (atomic64_add_unless(&zram->stats.bd_wb_limit, - -1 << (PAGE_SHIFT - 12), 0)) { - if (atomic64_read(&zram->stats.bd_wb_limit) == 0) - zram->stop_writeback = true; - } + spin_lock(&zram->wb_limit_lock); + if (zram->wb_limit_enable && zram->bd_wb_limit > 0) + zram->bd_wb_limit -= 1UL << (PAGE_SHIFT - 12); + spin_unlock(&zram->wb_limit_lock); next: zram_slot_unlock(zram, index); } @@ -1812,6 +1850,7 @@ static DEVICE_ATTR_RW(comp_algorithm); static DEVICE_ATTR_RW(backing_dev); static DEVICE_ATTR_WO(writeback); static DEVICE_ATTR_RW(writeback_limit); +static DEVICE_ATTR_RW(writeback_limit_enable); #endif static struct attribute *zram_disk_attrs[] = { @@ -1828,6 +1867,7 @@ static struct attribute *zram_disk_attrs[] = { &dev_attr_backing_dev.attr, &dev_attr_writeback.attr, &dev_attr_writeback_limit.attr, + &dev_attr_writeback_limit_enable.attr, #endif &dev_attr_io_stat.attr, &dev_attr_mm_stat.attr, @@ -1867,7 +1907,9 @@ static int zram_add(void) device_id = ret; init_rwsem(&zram->init_lock); - +#ifdef CONFIG_ZRAM_WRITEBACK + spin_lock_init(&zram->wb_limit_lock); +#endif queue = blk_alloc_queue(GFP_KERNEL); if (!queue) { pr_err("Error allocating disk queue for device %d\n", |