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linux-stable/fs/f2fs/inode.c
Chao Yu 81114baa83 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>
2018-05-31 11:31:45 -07:00

646 lines
17 KiB
C
Raw Blame History

/*
* fs/f2fs/inode.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/buffer_head.h>
#include <linux/backing-dev.h>
#include <linux/writeback.h>
#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include <trace/events/f2fs.h>
void f2fs_mark_inode_dirty_sync(struct inode *inode, bool sync)
{
if (is_inode_flag_set(inode, FI_NEW_INODE))
return;
if (f2fs_inode_dirtied(inode, sync))
return;
mark_inode_dirty_sync(inode);
}
void f2fs_set_inode_flags(struct inode *inode)
{
unsigned int flags = F2FS_I(inode)->i_flags;
unsigned int new_fl = 0;
if (flags & F2FS_SYNC_FL)
new_fl |= S_SYNC;
if (flags & F2FS_APPEND_FL)
new_fl |= S_APPEND;
if (flags & F2FS_IMMUTABLE_FL)
new_fl |= S_IMMUTABLE;
if (flags & F2FS_NOATIME_FL)
new_fl |= S_NOATIME;
if (flags & F2FS_DIRSYNC_FL)
new_fl |= S_DIRSYNC;
if (f2fs_encrypted_inode(inode))
new_fl |= S_ENCRYPTED;
inode_set_flags(inode, new_fl,
S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|
S_ENCRYPTED);
}
static void __get_inode_rdev(struct inode *inode, struct f2fs_inode *ri)
{
int extra_size = get_extra_isize(inode);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
if (ri->i_addr[extra_size])
inode->i_rdev = old_decode_dev(
le32_to_cpu(ri->i_addr[extra_size]));
else
inode->i_rdev = new_decode_dev(
le32_to_cpu(ri->i_addr[extra_size + 1]));
}
}
static bool __written_first_block(struct f2fs_inode *ri)
{
block_t addr = le32_to_cpu(ri->i_addr[offset_in_addr(ri)]);
if (addr != NEW_ADDR && addr != NULL_ADDR)
return true;
return false;
}
static void __set_inode_rdev(struct inode *inode, struct f2fs_inode *ri)
{
int extra_size = get_extra_isize(inode);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
if (old_valid_dev(inode->i_rdev)) {
ri->i_addr[extra_size] =
cpu_to_le32(old_encode_dev(inode->i_rdev));
ri->i_addr[extra_size + 1] = 0;
} else {
ri->i_addr[extra_size] = 0;
ri->i_addr[extra_size + 1] =
cpu_to_le32(new_encode_dev(inode->i_rdev));
ri->i_addr[extra_size + 2] = 0;
}
}
}
static void __recover_inline_status(struct inode *inode, struct page *ipage)
{
void *inline_data = inline_data_addr(inode, ipage);
__le32 *start = inline_data;
__le32 *end = start + MAX_INLINE_DATA(inode) / sizeof(__le32);
while (start < end) {
if (*start++) {
f2fs_wait_on_page_writeback(ipage, NODE, true);
set_inode_flag(inode, FI_DATA_EXIST);
set_raw_inline(inode, F2FS_INODE(ipage));
set_page_dirty(ipage);
return;
}
}
return;
}
static bool f2fs_enable_inode_chksum(struct f2fs_sb_info *sbi, struct page *page)
{
struct f2fs_inode *ri = &F2FS_NODE(page)->i;
int extra_isize = le32_to_cpu(ri->i_extra_isize);
if (!f2fs_sb_has_inode_chksum(sbi->sb))
return false;
if (!RAW_IS_INODE(F2FS_NODE(page)) || !(ri->i_inline & F2FS_EXTRA_ATTR))
return false;
if (!F2FS_FITS_IN_INODE(ri, extra_isize, i_inode_checksum))
return false;
return true;
}
static __u32 f2fs_inode_chksum(struct f2fs_sb_info *sbi, struct page *page)
{
struct f2fs_node *node = F2FS_NODE(page);
struct f2fs_inode *ri = &node->i;
__le32 ino = node->footer.ino;
__le32 gen = ri->i_generation;
__u32 chksum, chksum_seed;
__u32 dummy_cs = 0;
unsigned int offset = offsetof(struct f2fs_inode, i_inode_checksum);
unsigned int cs_size = sizeof(dummy_cs);
chksum = f2fs_chksum(sbi, sbi->s_chksum_seed, (__u8 *)&ino,
sizeof(ino));
chksum_seed = f2fs_chksum(sbi, chksum, (__u8 *)&gen, sizeof(gen));
chksum = f2fs_chksum(sbi, chksum_seed, (__u8 *)ri, offset);
chksum = f2fs_chksum(sbi, chksum, (__u8 *)&dummy_cs, cs_size);
offset += cs_size;
chksum = f2fs_chksum(sbi, chksum, (__u8 *)ri + offset,
F2FS_BLKSIZE - offset);
return chksum;
}
bool f2fs_inode_chksum_verify(struct f2fs_sb_info *sbi, struct page *page)
{
struct f2fs_inode *ri;
__u32 provided, calculated;
if (!f2fs_enable_inode_chksum(sbi, page) ||
PageDirty(page) || PageWriteback(page))
return true;
ri = &F2FS_NODE(page)->i;
provided = le32_to_cpu(ri->i_inode_checksum);
calculated = f2fs_inode_chksum(sbi, page);
if (provided != calculated)
f2fs_msg(sbi->sb, KERN_WARNING,
"checksum invalid, ino = %x, %x vs. %x",
ino_of_node(page), provided, calculated);
return provided == calculated;
}
void f2fs_inode_chksum_set(struct f2fs_sb_info *sbi, struct page *page)
{
struct f2fs_inode *ri = &F2FS_NODE(page)->i;
if (!f2fs_enable_inode_chksum(sbi, page))
return;
ri->i_inode_checksum = cpu_to_le32(f2fs_inode_chksum(sbi, page));
}
static int do_read_inode(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct f2fs_inode_info *fi = F2FS_I(inode);
struct page *node_page;
struct f2fs_inode *ri;
projid_t i_projid;
/* Check if ino is within scope */
if (check_nid_range(sbi, inode->i_ino)) {
f2fs_msg(inode->i_sb, KERN_ERR, "bad inode number: %lu",
(unsigned long) inode->i_ino);
WARN_ON(1);
return -EINVAL;
}
node_page = get_node_page(sbi, inode->i_ino);
if (IS_ERR(node_page))
return PTR_ERR(node_page);
ri = F2FS_INODE(node_page);
inode->i_mode = le16_to_cpu(ri->i_mode);
i_uid_write(inode, le32_to_cpu(ri->i_uid));
i_gid_write(inode, le32_to_cpu(ri->i_gid));
set_nlink(inode, le32_to_cpu(ri->i_links));
inode->i_size = le64_to_cpu(ri->i_size);
inode->i_blocks = SECTOR_FROM_BLOCK(le64_to_cpu(ri->i_blocks) - 1);
inode->i_atime.tv_sec = le64_to_cpu(ri->i_atime);
inode->i_ctime.tv_sec = le64_to_cpu(ri->i_ctime);
inode->i_mtime.tv_sec = le64_to_cpu(ri->i_mtime);
inode->i_atime.tv_nsec = le32_to_cpu(ri->i_atime_nsec);
inode->i_ctime.tv_nsec = le32_to_cpu(ri->i_ctime_nsec);
inode->i_mtime.tv_nsec = le32_to_cpu(ri->i_mtime_nsec);
inode->i_generation = le32_to_cpu(ri->i_generation);
fi->i_current_depth = le32_to_cpu(ri->i_current_depth);
fi->i_xattr_nid = le32_to_cpu(ri->i_xattr_nid);
fi->i_flags = le32_to_cpu(ri->i_flags);
fi->flags = 0;
fi->i_advise = ri->i_advise;
fi->i_pino = le32_to_cpu(ri->i_pino);
fi->i_dir_level = ri->i_dir_level;
if (f2fs_init_extent_tree(inode, &ri->i_ext))
set_page_dirty(node_page);
get_inline_info(inode, ri);
fi->i_extra_isize = f2fs_has_extra_attr(inode) ?
le16_to_cpu(ri->i_extra_isize) : 0;
if (f2fs_sb_has_flexible_inline_xattr(sbi->sb)) {
f2fs_bug_on(sbi, !f2fs_has_extra_attr(inode));
fi->i_inline_xattr_size = le16_to_cpu(ri->i_inline_xattr_size);
} else if (f2fs_has_inline_xattr(inode) ||
f2fs_has_inline_dentry(inode)) {
fi->i_inline_xattr_size = DEFAULT_INLINE_XATTR_ADDRS;
} else {
/*
* Previous inline data or directory always reserved 200 bytes
* in inode layout, even if inline_xattr is disabled. In order
* to keep inline_dentry's structure for backward compatibility,
* we get the space back only from inline_data.
*/
fi->i_inline_xattr_size = 0;
}
/* check data exist */
if (f2fs_has_inline_data(inode) && !f2fs_exist_data(inode))
__recover_inline_status(inode, node_page);
/* get rdev by using inline_info */
__get_inode_rdev(inode, ri);
if (__written_first_block(ri))
set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
if (!need_inode_block_update(sbi, inode->i_ino))
fi->last_disk_size = inode->i_size;
if (fi->i_flags & F2FS_PROJINHERIT_FL)
set_inode_flag(inode, FI_PROJ_INHERIT);
if (f2fs_has_extra_attr(inode) && f2fs_sb_has_project_quota(sbi->sb) &&
F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_projid))
i_projid = (projid_t)le32_to_cpu(ri->i_projid);
else
i_projid = F2FS_DEF_PROJID;
fi->i_projid = make_kprojid(&init_user_ns, i_projid);
if (f2fs_has_extra_attr(inode) && f2fs_sb_has_inode_crtime(sbi->sb) &&
F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_crtime)) {
fi->i_crtime.tv_sec = le64_to_cpu(ri->i_crtime);
fi->i_crtime.tv_nsec = le32_to_cpu(ri->i_crtime_nsec);
}
F2FS_I(inode)->i_disk_time[0] = inode->i_atime;
F2FS_I(inode)->i_disk_time[1] = inode->i_ctime;
F2FS_I(inode)->i_disk_time[2] = inode->i_mtime;
F2FS_I(inode)->i_disk_time[3] = F2FS_I(inode)->i_crtime;
f2fs_put_page(node_page, 1);
stat_inc_inline_xattr(inode);
stat_inc_inline_inode(inode);
stat_inc_inline_dir(inode);
return 0;
}
struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
struct inode *inode;
int ret = 0;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW)) {
trace_f2fs_iget(inode);
return inode;
}
if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
goto make_now;
ret = do_read_inode(inode);
if (ret)
goto bad_inode;
make_now:
if (ino == F2FS_NODE_INO(sbi)) {
inode->i_mapping->a_ops = &f2fs_node_aops;
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_NOFS);
} else if (S_ISREG(inode->i_mode)) {
inode->i_op = &f2fs_file_inode_operations;
inode->i_fop = &f2fs_file_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &f2fs_dir_inode_operations;
inode->i_fop = &f2fs_dir_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
inode_nohighmem(inode);
} else if (S_ISLNK(inode->i_mode)) {
if (f2fs_encrypted_inode(inode))
inode->i_op = &f2fs_encrypted_symlink_inode_operations;
else
inode->i_op = &f2fs_symlink_inode_operations;
inode_nohighmem(inode);
inode->i_mapping->a_ops = &f2fs_dblock_aops;
} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
inode->i_op = &f2fs_special_inode_operations;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
} else {
ret = -EIO;
goto bad_inode;
}
f2fs_set_inode_flags(inode);
unlock_new_inode(inode);
trace_f2fs_iget(inode);
return inode;
bad_inode:
iget_failed(inode);
trace_f2fs_iget_exit(inode, ret);
return ERR_PTR(ret);
}
struct inode *f2fs_iget_retry(struct super_block *sb, unsigned long ino)
{
struct inode *inode;
retry:
inode = f2fs_iget(sb, ino);
if (IS_ERR(inode)) {
if (PTR_ERR(inode) == -ENOMEM) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
goto retry;
}
}
return inode;
}
void update_inode(struct inode *inode, struct page *node_page)
{
struct f2fs_inode *ri;
struct extent_tree *et = F2FS_I(inode)->extent_tree;
f2fs_wait_on_page_writeback(node_page, NODE, true);
set_page_dirty(node_page);
f2fs_inode_synced(inode);
ri = F2FS_INODE(node_page);
ri->i_mode = cpu_to_le16(inode->i_mode);
ri->i_advise = F2FS_I(inode)->i_advise;
ri->i_uid = cpu_to_le32(i_uid_read(inode));
ri->i_gid = cpu_to_le32(i_gid_read(inode));
ri->i_links = cpu_to_le32(inode->i_nlink);
ri->i_size = cpu_to_le64(i_size_read(inode));
ri->i_blocks = cpu_to_le64(SECTOR_TO_BLOCK(inode->i_blocks) + 1);
if (et) {
read_lock(&et->lock);
set_raw_extent(&et->largest, &ri->i_ext);
read_unlock(&et->lock);
} else {
memset(&ri->i_ext, 0, sizeof(ri->i_ext));
}
set_raw_inline(inode, ri);
ri->i_atime = cpu_to_le64(inode->i_atime.tv_sec);
ri->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
ri->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
ri->i_atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
ri->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
ri->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
ri->i_current_depth = cpu_to_le32(F2FS_I(inode)->i_current_depth);
ri->i_xattr_nid = cpu_to_le32(F2FS_I(inode)->i_xattr_nid);
ri->i_flags = cpu_to_le32(F2FS_I(inode)->i_flags);
ri->i_pino = cpu_to_le32(F2FS_I(inode)->i_pino);
ri->i_generation = cpu_to_le32(inode->i_generation);
ri->i_dir_level = F2FS_I(inode)->i_dir_level;
if (f2fs_has_extra_attr(inode)) {
ri->i_extra_isize = cpu_to_le16(F2FS_I(inode)->i_extra_isize);
if (f2fs_sb_has_flexible_inline_xattr(F2FS_I_SB(inode)->sb))
ri->i_inline_xattr_size =
cpu_to_le16(F2FS_I(inode)->i_inline_xattr_size);
if (f2fs_sb_has_project_quota(F2FS_I_SB(inode)->sb) &&
F2FS_FITS_IN_INODE(ri, F2FS_I(inode)->i_extra_isize,
i_projid)) {
projid_t i_projid;
i_projid = from_kprojid(&init_user_ns,
F2FS_I(inode)->i_projid);
ri->i_projid = cpu_to_le32(i_projid);
}
if (f2fs_sb_has_inode_crtime(F2FS_I_SB(inode)->sb) &&
F2FS_FITS_IN_INODE(ri, F2FS_I(inode)->i_extra_isize,
i_crtime)) {
ri->i_crtime =
cpu_to_le64(F2FS_I(inode)->i_crtime.tv_sec);
ri->i_crtime_nsec =
cpu_to_le32(F2FS_I(inode)->i_crtime.tv_nsec);
}
}
__set_inode_rdev(inode, ri);
/* deleted inode */
if (inode->i_nlink == 0)
clear_inline_node(node_page);
F2FS_I(inode)->i_disk_time[0] = inode->i_atime;
F2FS_I(inode)->i_disk_time[1] = inode->i_ctime;
F2FS_I(inode)->i_disk_time[2] = inode->i_mtime;
F2FS_I(inode)->i_disk_time[3] = F2FS_I(inode)->i_crtime;
}
void update_inode_page(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct page *node_page;
retry:
node_page = get_node_page(sbi, inode->i_ino);
if (IS_ERR(node_page)) {
int err = PTR_ERR(node_page);
if (err == -ENOMEM) {
cond_resched();
goto retry;
} else if (err != -ENOENT) {
f2fs_stop_checkpoint(sbi, false);
}
return;
}
update_inode(inode, node_page);
f2fs_put_page(node_page, 1);
}
int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
if (inode->i_ino == F2FS_NODE_INO(sbi) ||
inode->i_ino == F2FS_META_INO(sbi))
return 0;
if (!is_inode_flag_set(inode, FI_DIRTY_INODE))
return 0;
/*
* We need to balance fs here to prevent from producing dirty node pages
* during the urgent cleaning time when runing out of free sections.
*/
update_inode_page(inode);
if (wbc && wbc->nr_to_write)
f2fs_balance_fs(sbi, true);
return 0;
}
/*
* Called at the last iput() if i_nlink is zero
*/
void f2fs_evict_inode(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
nid_t xnid = F2FS_I(inode)->i_xattr_nid;
int err = 0;
/* some remained atomic pages should discarded */
if (f2fs_is_atomic_file(inode))
drop_inmem_pages(inode);
trace_f2fs_evict_inode(inode);
truncate_inode_pages_final(&inode->i_data);
if (inode->i_ino == F2FS_NODE_INO(sbi) ||
inode->i_ino == F2FS_META_INO(sbi))
goto out_clear;
f2fs_bug_on(sbi, get_dirty_pages(inode));
remove_dirty_inode(inode);
f2fs_destroy_extent_tree(inode);
if (inode->i_nlink || is_bad_inode(inode))
goto no_delete;
dquot_initialize(inode);
remove_ino_entry(sbi, inode->i_ino, APPEND_INO);
remove_ino_entry(sbi, inode->i_ino, UPDATE_INO);
remove_ino_entry(sbi, inode->i_ino, FLUSH_INO);
sb_start_intwrite(inode->i_sb);
set_inode_flag(inode, FI_NO_ALLOC);
i_size_write(inode, 0);
retry:
if (F2FS_HAS_BLOCKS(inode))
err = f2fs_truncate(inode);
#ifdef CONFIG_F2FS_FAULT_INJECTION
if (time_to_inject(sbi, FAULT_EVICT_INODE)) {
f2fs_show_injection_info(FAULT_EVICT_INODE);
err = -EIO;
}
#endif
if (!err) {
f2fs_lock_op(sbi);
err = remove_inode_page(inode);
f2fs_unlock_op(sbi);
if (err == -ENOENT)
err = 0;
}
/* give more chances, if ENOMEM case */
if (err == -ENOMEM) {
err = 0;
goto retry;
}
if (err)
update_inode_page(inode);
dquot_free_inode(inode);
sb_end_intwrite(inode->i_sb);
no_delete:
dquot_drop(inode);
stat_dec_inline_xattr(inode);
stat_dec_inline_dir(inode);
stat_dec_inline_inode(inode);
if (likely(!is_set_ckpt_flags(sbi, CP_ERROR_FLAG)))
f2fs_bug_on(sbi, is_inode_flag_set(inode, FI_DIRTY_INODE));
else
f2fs_inode_synced(inode);
/* ino == 0, if f2fs_new_inode() was failed t*/
if (inode->i_ino)
invalidate_mapping_pages(NODE_MAPPING(sbi), inode->i_ino,
inode->i_ino);
if (xnid)
invalidate_mapping_pages(NODE_MAPPING(sbi), xnid, xnid);
if (inode->i_nlink) {
if (is_inode_flag_set(inode, FI_APPEND_WRITE))
add_ino_entry(sbi, inode->i_ino, APPEND_INO);
if (is_inode_flag_set(inode, FI_UPDATE_WRITE))
add_ino_entry(sbi, inode->i_ino, UPDATE_INO);
}
if (is_inode_flag_set(inode, FI_FREE_NID)) {
alloc_nid_failed(sbi, inode->i_ino);
clear_inode_flag(inode, FI_FREE_NID);
} else {
f2fs_bug_on(sbi, err &&
!exist_written_data(sbi, inode->i_ino, ORPHAN_INO));
}
out_clear:
fscrypt_put_encryption_info(inode);
clear_inode(inode);
}
/* caller should call f2fs_lock_op() */
void handle_failed_inode(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct node_info ni;
/*
* clear nlink of inode in order to release resource of inode
* immediately.
*/
clear_nlink(inode);
/*
* we must call this to avoid inode being remained as dirty, resulting
* in a panic when flushing dirty inodes in gdirty_list.
*/
update_inode_page(inode);
f2fs_inode_synced(inode);
/* don't make bad inode, since it becomes a regular file. */
unlock_new_inode(inode);
/*
* Note: we should add inode to orphan list before f2fs_unlock_op()
* so we can prevent losing this orphan when encoutering checkpoint
* and following suddenly power-off.
*/
get_node_info(sbi, inode->i_ino, &ni);
if (ni.blk_addr != NULL_ADDR) {
int err = acquire_orphan_inode(sbi);
if (err) {
set_sbi_flag(sbi, SBI_NEED_FSCK);
f2fs_msg(sbi->sb, KERN_WARNING,
"Too many orphan inodes, run fsck to fix.");
} else {
add_orphan_inode(inode);
}
alloc_nid_done(sbi, inode->i_ino);
} else {
set_inode_flag(inode, FI_FREE_NID);
}
f2fs_unlock_op(sbi);
/* iput will drop the inode object */
iput(inode);
}
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