On Tue, Apr 04, 2017 at 11:31:15AM +0900, Sergey Senozhatsky wrote:
> On (04/03/17 14:17), Minchan Kim wrote:
> [..]
> > -static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
> > +static bool zram_meta_alloc(struct zram *zram, u64 disksize)
> > {
> > size_t num_pages;
> > - struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
> > -
> > - if (!meta)
> > - return NULL;
> >
> > 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 out_error;
> > - }
> > + zram->table = vzalloc(num_pages * sizeof(*zram->table));
> > + if (!zram->table)
> > + return false;
> >
> > - meta->mem_pool = zs_create_pool(pool_name);
> > - if (!meta->mem_pool) {
> > - pr_err("Error creating memory pool\n");
> > - goto out_error;
> > + zram->mem_pool = zs_create_pool(zram->disk->disk_name);
> > + if (!zram->mem_pool) {
> > + vfree(zram->table);
> > + return false;
> > }
> >
> > - return meta;
> > -
> > -out_error:
> > - vfree(meta->table);
> > - kfree(meta);
> > - return NULL;
> > + return true;
> > }
>
> [..]
>
> > @@ -1020,7 +989,6 @@ static ssize_t disksize_store(struct device *dev,
> > {
> > u64 disksize;
> > struct zcomp *comp;
> > - struct zram_meta *meta;
> > struct zram *zram = dev_to_zram(dev);
> > int err;
> >
> > @@ -1029,8 +997,7 @@ static ssize_t disksize_store(struct device *dev,
> > return -EINVAL;
> >
> > disksize = PAGE_ALIGN(disksize);
> > - meta = zram_meta_alloc(zram->disk->disk_name, disksize);
> > - if (!meta)
> > + if (!zram_meta_alloc(zram, disksize))
> > return -ENOMEM;
> >
> > comp = zcomp_create(zram->compressor);
> > @@ -1048,7 +1015,6 @@ static ssize_t disksize_store(struct device *dev,
> > goto out_destroy_comp;
> > }
> >
> > - zram->meta = meta;
> > zram->comp = comp;
> > zram->disksize = disksize;
> > set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
> > @@ -1061,7 +1027,7 @@ static ssize_t disksize_store(struct device *dev,
> > up_write(&zram->init_lock);
> > zcomp_destroy(comp);
> > out_free_meta:
> > - zram_meta_free(meta, disksize);
> > + zram_meta_free(zram, disksize);
> > return err;
> > }
>
> OK, I don't think it's the same.
>
> we used to have
>
> struct zram_meta *zram_meta_alloc()
> {
> meta->table = vzalloc()
> meta->mem_pool = zs_create_pool();
> return meta;
> }
>
>
> disksize_store()
> {
> meta = zram_meta_alloc();
> if (init_done(zram)) {
> pr_info("Cannot change disksize for initialized
> device\n");
> goto out_destroy_comp;
> }
>
> zram->meta = meta;
> ^^^^^^^^^^^^^^^^^^
> }
>
> now we have
>
> struct zram_meta *zram_meta_alloc()
> {
> zram->table = vzalloc()
> zram->mem_pool = zs_create_pool();
> return true;
> }
>
>
> disksize_store()
> {
> zram_meta_alloc();
> ^^^^^^^^^^^^^^^^^
> if (init_done(zram)) {
> pr_info("Cannot change disksize for initialized
> device\n");
> goto out_destroy_comp;
> }
> }
>
>
> by the time we call init_done(zram) on already init device zram->table
> and zram->mem_pool are overwritten and lost. right?
Right you are.
I will fix it!
>
>
> [..]
> > -struct zram_meta {
> > +struct zram {
> > struct zram_table_entry *table;
> > struct zs_pool *mem_pool;
> > -};
> > -
> > -struct zram {
> > - struct zram_meta *meta;
> > struct zcomp *comp;
> > struct gendisk *disk;
> > /* Prevent concurrent execution of device init */
>
>
> we still have several zram_meta_FOO() left overs in zram_drv.c
>
> -ss
