f2fs: don't use GFP_ZERO for page caches

commit 81114baa835b59ed02d14aa1d67f91ea874077cd upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index bf779461df13dee9232eb9ff057b6c4c3572a0c3..2e23b953d30470544bd1c4332e16c6ea1e970d5e 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -100,8 +100,10 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
         * 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 e0d9e8f27ed2b1ea3bf2f92f883d07caa7fde7a8..f8ef04c9f69df2cbb8e79024a84bb687c8964249 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 5854cc4e1d67c01045f41b99403aaaefbfc27894..be8d1b16b8d117cdd00cbb186fc0a2a22fde4fe1 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2020,6 +2020,7 @@ 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);
 
@@ -3116,6 +3117,7 @@ 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);
@@ -3140,6 +3142,7 @@ 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);