zram: move comp allocation out of init_lock

[cascardo/linux.git] / drivers / block / zram / zram_drv.c

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 98823f9..e4d536b 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -108,6 +108,67 @@ static ssize_t mem_used_total_show(struct device *dev,
        return sprintf(buf, "%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 sprintf(buf, "%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);
+
+       if (kstrtoint(buf, 0, &num))
+               return -EINVAL;
+       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");
+       }
+       zram->max_comp_streams = num;
+       up_write(&zram->init_lock);
+       return len;
+}
+
+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 */
 static int zram_test_flag(struct zram_meta *meta, u32 index,
                        enum zram_pageflags flag)
@@ -502,6 +563,8 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity)
        }
 
        zcomp_destroy(zram->comp);
+       zram->max_comp_streams = 1;
+
        zram_meta_free(zram->meta);
        zram->meta = NULL;
        /* Reset stats */
@@ -517,9 +580,10 @@ 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;
+       int err = -EINVAL;
 
        disksize = memparse(buf, NULL);
        if (!disksize)
@@ -530,30 +594,32 @@ static ssize_t disksize_store(struct device *dev,
        if (!meta)
                return -ENOMEM;
 
+       comp = zcomp_create(zram->compressor, zram->max_comp_streams);
+       if (!comp) {
+               pr_info("Cannot initialise %s compressing backend\n",
+                               zram->compressor);
+               goto out_cleanup;
+       }
+
        down_write(&zram->init_lock);
        if (init_done(zram)) {
+               up_write(&zram->init_lock);
                pr_info("Cannot change disksize for initialized device\n");
                err = -EBUSY;
-               goto out_free_meta;
-       }
-
-       zram->comp = zcomp_create(default_compressor);
-       if (!zram->comp) {
-               pr_info("Cannot initialise %s compressing backend\n",
-                               default_compressor);
-               err = -EINVAL;
-               goto out_free_meta;
+               goto out_cleanup;
        }
 
        zram->meta = meta;
+       zram->comp = comp;
        zram->disksize = disksize;
        set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
        up_write(&zram->init_lock);
 
        return len;
 
-out_free_meta:
-       up_write(&zram->init_lock);
+out_cleanup:
+       if (comp)
+               zcomp_destroy(comp);
        zram_meta_free(meta);
        return err;
 }
@@ -698,6 +764,10 @@ static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL);
 static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store);
 static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_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);
@@ -722,6 +792,8 @@ static struct attribute *zram_disk_attrs[] = {
        &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,
 };
 
@@ -782,8 +854,9 @@ static int create_device(struct zram *zram, int device_id)
                pr_warn("Error creating sysfs group");
                goto out_free_disk;
        }
-
+       strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));
        zram->meta = NULL;
+       zram->max_comp_streams = 1;
        return 0;
 
 out_free_disk: