f2fs: Add option to limit required GC for checkpoint=disable
This extends the checkpoint option to allow checkpoint=disable:%u[%]
This allows you to specify what how much of the disk you are willing
to lose access to while mounting with checkpoint=disable. If the amount
lost would be higher, the mount will return -EAGAIN. This can be given
as a percent of total space, or in blocks.
Currently, we need to run garbage collection until the amount of holes
is smaller than the OVP space. With the new option, f2fs can mark
space as unusable up front instead of requiring garbage collection until
the number of holes is small enough.
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 75801ea..4347bba 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -138,6 +138,9 @@
int alloc_mode; /* segment allocation policy */
int fsync_mode; /* fsync policy */
bool test_dummy_encryption; /* test dummy encryption */
+ block_t unusable_cap; /* Amount of space allowed to be
+ * unusable when disabling checkpoint
+ */
};
#define F2FS_FEATURE_ENCRYPT 0x0001
@@ -3116,7 +3119,8 @@
void f2fs_clear_prefree_segments(struct f2fs_sb_info *sbi,
struct cp_control *cpc);
void f2fs_dirty_to_prefree(struct f2fs_sb_info *sbi);
-int f2fs_disable_cp_again(struct f2fs_sb_info *sbi);
+block_t f2fs_get_unusable_blocks(struct f2fs_sb_info *sbi);
+int f2fs_disable_cp_again(struct f2fs_sb_info *sbi, block_t unusable);
void f2fs_release_discard_addrs(struct f2fs_sb_info *sbi);
int f2fs_npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi);