diff options
| -rw-r--r-- | drivers/staging/zram/zram_drv.c | 35 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_drv.h | 2 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_sysfs.c | 26 |
3 files changed, 29 insertions, 34 deletions
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 3f698a5..c5f84ee 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -207,9 +207,15 @@ static int zram_read(struct zram *zram, struct bio *bio) u32 index; struct bio_vec *bvec; - zram_stat64_inc(zram, &zram->stats.num_reads); + if (unlikely(!zram->init_done)) { + set_bit(BIO_UPTODATE, &bio->bi_flags); + bio_endio(bio, 0); + return 0; + } + zram_stat64_inc(zram, &zram->stats.num_reads); index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; + bio_for_each_segment(bvec, bio, i) { int ret; size_t clen; @@ -275,16 +281,20 @@ out: static int zram_write(struct zram *zram, struct bio *bio) { - int i; + int i, ret; u32 index; struct bio_vec *bvec; - zram_stat64_inc(zram, &zram->stats.num_writes); + if (unlikely(!zram->init_done)) { + ret = zram_init_device(zram); + if (ret) + goto out; + } + zram_stat64_inc(zram, &zram->stats.num_writes); index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; bio_for_each_segment(bvec, bio, i) { - int ret; u32 offset; size_t clen; struct zobj_header *zheader; @@ -425,11 +435,6 @@ static int zram_make_request(struct request_queue *queue, struct bio *bio) int ret = 0; struct zram *zram = queue->queuedata; - if (unlikely(!zram->init_done)) { - bio_io_error(bio); - return 0; - } - if (!valid_io_request(zram, bio)) { zram_stat64_inc(zram, &zram->stats.invalid_io); bio_io_error(bio); @@ -453,7 +458,7 @@ void zram_reset_device(struct zram *zram) { size_t index; - /* Do not accept any new I/O request */ + mutex_lock(&zram->init_lock); zram->init_done = 0; /* Free various per-device buffers */ @@ -490,6 +495,7 @@ void zram_reset_device(struct zram *zram) memset(&zram->stats, 0, sizeof(zram->stats)); zram->disksize = 0; + mutex_unlock(&zram->init_lock); } int zram_init_device(struct zram *zram) @@ -497,9 +503,11 @@ int zram_init_device(struct zram *zram) int ret; size_t num_pages; + mutex_lock(&zram->init_lock); + if (zram->init_done) { - pr_info("Device already initialized!\n"); - return -EBUSY; + mutex_unlock(&zram->init_lock); + return 0; } zram_set_disksize(zram, totalram_pages << PAGE_SHIFT); @@ -542,11 +550,13 @@ int zram_init_device(struct zram *zram) } zram->init_done = 1; + mutex_unlock(&zram->init_lock); pr_debug("Initialization done!\n"); return 0; fail: + mutex_unlock(&zram->init_lock); zram_reset_device(zram); pr_err("Initialization failed: err=%d\n", ret); @@ -572,6 +582,7 @@ static int create_device(struct zram *zram, int device_id) int ret = 0; mutex_init(&zram->lock); + mutex_init(&zram->init_lock); spin_lock_init(&zram->stat64_lock); zram->queue = blk_alloc_queue(GFP_KERNEL); diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h index 2ef93cc..a481551 100644 --- a/drivers/staging/zram/zram_drv.h +++ b/drivers/staging/zram/zram_drv.h @@ -108,6 +108,8 @@ struct zram { struct request_queue *queue; struct gendisk *disk; int init_done; + /* Prevent concurrent execution of device init and reset */ + struct mutex init_lock; /* * This is the limit on amount of *uncompressed* worth of data * we can store in a disk. diff --git a/drivers/staging/zram/zram_sysfs.c b/drivers/staging/zram/zram_sysfs.c index b8dbaee..6c574a9 100644 --- a/drivers/staging/zram/zram_sysfs.c +++ b/drivers/staging/zram/zram_sysfs.c @@ -58,8 +58,10 @@ static ssize_t disksize_store(struct device *dev, int ret; struct zram *zram = dev_to_zram(dev); - if (zram->init_done) + if (zram->init_done) { + pr_info("Cannot change disksize for initialized device\n"); return -EBUSY; + } ret = strict_strtoull(buf, 10, &zram->disksize); if (ret) @@ -79,25 +81,6 @@ static ssize_t initstate_show(struct device *dev, return sprintf(buf, "%u\n", zram->init_done); } -static ssize_t initstate_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t len) -{ - int ret; - unsigned long do_init; - struct zram *zram = dev_to_zram(dev); - - ret = strict_strtoul(buf, 10, &do_init); - if (ret) - return ret; - - if (!do_init) - return -EINVAL; - - zram_init_device(zram); - - return len; -} - static ssize_t reset_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -208,8 +191,7 @@ static ssize_t mem_used_total_show(struct device *dev, static DEVICE_ATTR(disksize, S_IRUGO | S_IWUGO, disksize_show, disksize_store); -static DEVICE_ATTR(initstate, S_IRUGO | S_IWUGO, - initstate_show, initstate_store); +static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL); static DEVICE_ATTR(reset, S_IWUGO, 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); |