diff options
Diffstat (limited to 'mm/zpool.c')
| -rw-r--r-- | mm/zpool.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/mm/zpool.c b/mm/zpool.c index fd3ff719c32c..e1e7aa6d1d06 100644 --- a/mm/zpool.c +++ b/mm/zpool.c @@ -21,6 +21,7 @@ struct zpool { struct zpool_driver *driver; void *pool; const struct zpool_ops *ops; + bool evictable; struct list_head list; }; @@ -142,7 +143,7 @@ EXPORT_SYMBOL(zpool_has_pool); * * This creates a new zpool of the specified type. The gfp flags will be * used when allocating memory, if the implementation supports it. If the - * ops param is NULL, then the created zpool will not be shrinkable. + * ops param is NULL, then the created zpool will not be evictable. * * Implementations must guarantee this to be thread-safe. * @@ -180,6 +181,7 @@ struct zpool *zpool_create_pool(const char *type, const char *name, gfp_t gfp, zpool->driver = driver; zpool->pool = driver->create(name, gfp, ops, zpool); zpool->ops = ops; + zpool->evictable = driver->shrink && ops && ops->evict; if (!zpool->pool) { pr_err("couldn't create %s pool\n", type); @@ -296,7 +298,8 @@ void zpool_free(struct zpool *zpool, unsigned long handle) int zpool_shrink(struct zpool *zpool, unsigned int pages, unsigned int *reclaimed) { - return zpool->driver->shrink(zpool->pool, pages, reclaimed); + return zpool->driver->shrink ? + zpool->driver->shrink(zpool->pool, pages, reclaimed) : -EINVAL; } /** @@ -355,6 +358,24 @@ u64 zpool_get_total_size(struct zpool *zpool) return zpool->driver->total_size(zpool->pool); } +/** + * zpool_evictable() - Test if zpool is potentially evictable + * @pool The zpool to test + * + * Zpool is only potentially evictable when it's created with struct + * zpool_ops.evict and its driver implements struct zpool_driver.shrink. + * + * However, it doesn't necessarily mean driver will use zpool_ops.evict + * in its implementation of zpool_driver.shrink. It could do internal + * defragmentation instead. + * + * Returns: true if potentially evictable; false otherwise. + */ +bool zpool_evictable(struct zpool *zpool) +{ + return zpool->evictable; +} + MODULE_LICENSE("GPL"); MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>"); MODULE_DESCRIPTION("Common API for compressed memory storage"); |