f2fs: don't use GFP_ZERO for page caches

Related to https://lkml.org/lkml/2018/4/8/661

Sometimes, we need to write meta data to new allocated block address,
then we will allocate a zeroed page in inner inode's address space, and
fill partial data in it, and leave other place with zero value which means
some fields are initial status.

There are two inner inodes (meta inode and node inode) setting __GFP_ZERO,
I have just checked them, for both of them, we can avoid using __GFP_ZERO,
and do initialization by ourselves to avoid unneeded/redundant zeroing
from mm.

Cc: <stable@vger.kernel.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 3d3a1f6b21a14c8bc62c08101ee45891ffb60005..8fc55d42ba25e7abe6b749b3feedcb6b5466014f 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -100,8 +100,10 @@ repeat:
         * readonly and make sure do not write checkpoint with non-uptodate
         * meta page.
         */
-       if (unlikely(!PageUptodate(page)))
+       if (unlikely(!PageUptodate(page))) {
+               memset(page_address(page), 0, PAGE_SIZE);
                f2fs_stop_checkpoint(sbi, false);
+       }
 out:
        return page;
 }

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 417c9dcd026993057ba54aac245d544fab9c84a7..87535bf63421f3fc15537f5538feef5bbc398d62 100644 (file)
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -320,10 +320,10 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
 make_now:
        if (ino == F2FS_NODE_INO(sbi)) {
                inode->i_mapping->a_ops = &f2fs_node_aops;
-               mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO);
+               mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
        } else if (ino == F2FS_META_INO(sbi)) {
                inode->i_mapping->a_ops = &f2fs_meta_aops;
-               mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO);
+               mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
        } else if (S_ISREG(inode->i_mode)) {
                inode->i_op = &f2fs_file_inode_operations;
                inode->i_fop = &f2fs_file_operations;

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index a7ec952093f8c2f62496402872cb62ee2bebfc2f..0fb006f591a4c51081f9487ce5c711cfa723e1f0 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1979,6 +1979,7 @@ static void write_current_sum_page(struct f2fs_sb_info *sbi,
        struct f2fs_summary_block *dst;
 
        dst = (struct f2fs_summary_block *)page_address(page);
+       memset(dst, 0, PAGE_SIZE);
 
        mutex_lock(&curseg->curseg_mutex);
 
@@ -3133,6 +3134,7 @@ static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
 
        page = grab_meta_page(sbi, blkaddr++);
        kaddr = (unsigned char *)page_address(page);
+       memset(kaddr, 0, PAGE_SIZE);
 
        /* Step 1: write nat cache */
        seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
@@ -3157,6 +3159,7 @@ static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
                        if (!page) {
                                page = grab_meta_page(sbi, blkaddr++);
                                kaddr = (unsigned char *)page_address(page);
+                               memset(kaddr, 0, PAGE_SIZE);
                                written_size = 0;
                        }
                        summary = (struct f2fs_summary *)(kaddr + written_size);

diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 3325d076972326d5f11cd7776fceb07a3fec5a14..492ad0c86fa999bd8391966b03f1daf11afe7d07 100644 (file)
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -375,6 +375,7 @@ static inline void seg_info_to_sit_page(struct f2fs_sb_info *sbi,
        int i;
 
        raw_sit = (struct f2fs_sit_block *)page_address(page);
+       memset(raw_sit, 0, PAGE_SIZE);
        for (i = 0; i < end - start; i++) {
                rs = &raw_sit->entries[i];
                se = get_seg_entry(sbi, start + i);