Add a sysfs node to drop compression-related caches, currently used to
drop in-memory pclusters and cached compressed folios.
Signed-off-by: Chunhai Guo <guochunhai at vivo.com>
---
v2->v3:
- All cached folios should be disconnected before invalidating.
- Only add sysfs node when CONFIG_EROFS_FS_ZIP is enabled.
v1: https://lore.kernel.org/linux-erofs/fabdfe9f-9293-45c2-8cf2-3d86c248ab4c@linux.alibaba.com
v1->v2:
- Change subject as suggested by Gao Xiang.
- Use different bits to indicate different meanings in the sysfs node.
---
Documentation/ABI/testing/sysfs-fs-erofs | 11 +++++++++++
fs/erofs/internal.h | 2 ++
fs/erofs/sysfs.c | 18 ++++++++++++++++++
fs/erofs/zdata.c | 1 -
4 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-fs-erofs b/Documentation/ABI/testing/sysfs-fs-erofs
index 284224d1b56f..b134146d735b 100644
--- a/Documentation/ABI/testing/sysfs-fs-erofs
+++ b/Documentation/ABI/testing/sysfs-fs-erofs
@@ -16,3 +16,14 @@ Description: Control strategy of sync decompression:
readahead on atomic contexts only.
- 1 (force on): enable for readpage and readahead.
- 2 (force off): disable for all situations.
+
+What: /sys/fs/erofs/<disk>/drop_caches
+Date: November 2024
+Contact: "Guo Chunhai" <guochunhai at vivo.com>
+Description: Writing to this will drop compression-related caches,
+ currently used to drop in-memory pclusters and cached
+ compressed folios:
+
+ - 1 : invalidate cached compressed folios
+ - 2 : drop in-memory pclusters
+ - 3 : drop in-memory pclusters and cached compressed folios
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 3905d991c49b..0328e6b98c1b 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -450,6 +450,8 @@ static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
void erofs_release_pages(struct page **pagepool);
#ifdef CONFIG_EROFS_FS_ZIP
+#define MNGD_MAPPING(sbi) ((sbi)->managed_cache->i_mapping)
+
extern atomic_long_t erofs_global_shrink_cnt;
void erofs_shrinker_register(struct super_block *sb);
void erofs_shrinker_unregister(struct super_block *sb);
diff --git a/fs/erofs/sysfs.c b/fs/erofs/sysfs.c
index 63cffd0fd261..4145b732d30f 100644
--- a/fs/erofs/sysfs.c
+++ b/fs/erofs/sysfs.c
@@ -10,6 +10,7 @@
enum {
attr_feature,
+ attr_drop_caches,
attr_pointer_ui,
attr_pointer_bool,
};
@@ -57,11 +58,13 @@ static struct erofs_attr erofs_attr_##_name = { \
#ifdef CONFIG_EROFS_FS_ZIP
EROFS_ATTR_RW_UI(sync_decompress, erofs_mount_opts);
+EROFS_ATTR_FUNC(drop_caches, 0200);
#endif
static struct attribute *erofs_attrs[] = {
#ifdef CONFIG_EROFS_FS_ZIP
ATTR_LIST(sync_decompress),
+ ATTR_LIST(drop_caches),
#endif
NULL,
};
@@ -163,6 +166,21 @@ static ssize_t erofs_attr_store(struct kobject *kobj, struct attribute *attr,
return -EINVAL;
*(bool *)ptr = !!t;
return len;
+#ifdef CONFIG_EROFS_FS_ZIP
+ case attr_drop_caches:
+ ret = kstrtoul(skip_spaces(buf), 0, &t);
+ if (ret)
+ return ret;
+ if (t < 1 || t > 3)
+ return -EINVAL;
+
+ if (t & 2)
+ z_erofs_shrink_scan(sbi, ~0UL);
+
+ if (t & 1)
+ invalidate_mapping_pages(MNGD_MAPPING(sbi), 0, -1);
+ return len;
+#endif
}
return 0;
}
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 877bce7709d5..01f147505487 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -119,7 +119,6 @@ static inline unsigned int z_erofs_pclusterpages(struct z_erofs_pcluster *pcl)
return PAGE_ALIGN(pcl->pclustersize) >> PAGE_SHIFT;
}
-#define MNGD_MAPPING(sbi) ((sbi)->managed_cache->i_mapping)
static bool erofs_folio_is_managed(struct erofs_sb_info *sbi, struct folio *fo)
{
return fo->mapping == MNGD_MAPPING(sbi);
--
2.34.1