/*
 * 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/writeback.h>

#include "f2fs.h"
#include "node.h"

#include <trace/events/f2fs.h>

void f2fs_set_inode_flags(struct inode *inode)
{
        unsigned int flags = F2FS_I(inode)->i_flags;

        inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE |
                        S_NOATIME | S_DIRSYNC);

        if (flags & FS_SYNC_FL)
                inode->i_flags |= S_SYNC;
        if (flags & FS_APPEND_FL)
                inode->i_flags |= S_APPEND;
        if (flags & FS_IMMUTABLE_FL)
                inode->i_flags |= S_IMMUTABLE;
        if (flags & FS_NOATIME_FL)
                inode->i_flags |= S_NOATIME;
        if (flags & FS_DIRSYNC_FL)
                inode->i_flags |= S_DIRSYNC;
}

static int do_read_inode(struct inode *inode)
{
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct page *node_page;
        struct f2fs_node *rn;
        struct f2fs_inode *ri;

        /* 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);
                return -EINVAL;
        }

        node_page = get_node_page(sbi, inode->i_ino);
        if (IS_ERR(node_page))
                return PTR_ERR(node_page);

        rn = F2FS_NODE(node_page);
        ri = &(rn->i);

        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 = le64_to_cpu(ri->i_blocks);

        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);
        if (ri->i_addr[0])
                inode->i_rdev = old_decode_dev(le32_to_cpu(ri->i_addr[0]));
        else
                inode->i_rdev = new_decode_dev(le32_to_cpu(ri->i_addr[1]));

        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);
        get_extent_info(&fi->ext, ri->i_ext);
        get_inline_info(fi, ri);
        f2fs_put_page(node_page, 1);
        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_F2FS_ZERO);
        } 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);
        } 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;
                mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO);
        } else if (S_ISLNK(inode->i_mode)) {
                inode->i_op = &f2fs_symlink_inode_operations;
                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;
        }
        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);
}

void update_inode(struct inode *inode, struct page *node_page)
{
        struct f2fs_node *rn;
        struct f2fs_inode *ri;

        f2fs_wait_on_page_writeback(node_page, NODE, false);

        rn = F2FS_NODE(node_page);
        ri = &(rn->i);

        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(inode->i_blocks);
        set_raw_extent(&F2FS_I(inode)->ext, &ri->i_ext);
        set_raw_inline(F2FS_I(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);

        if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
                if (old_valid_dev(inode->i_rdev)) {
                        ri->i_addr[0] =
                                cpu_to_le32(old_encode_dev(inode->i_rdev));
                        ri->i_addr[1] = 0;
                } else {
                        ri->i_addr[0] = 0;
                        ri->i_addr[1] =
                                cpu_to_le32(new_encode_dev(inode->i_rdev));
                        ri->i_addr[2] = 0;
                }
        }

        set_cold_node(inode, node_page);
        set_page_dirty(node_page);
        clear_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
}

int update_inode_page(struct inode *inode)
{
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        struct page *node_page;

        node_page = get_node_page(sbi, inode->i_ino);
        if (IS_ERR(node_page))
                return PTR_ERR(node_page);

        update_inode(inode, node_page);
        f2fs_put_page(node_page, 1);
        return 0;
}

int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        int ret, ilock;

        if (inode->i_ino == F2FS_NODE_INO(sbi) ||
                        inode->i_ino == F2FS_META_INO(sbi))
                return 0;

        if (!is_inode_flag_set(F2FS_I(inode), FI_DIRTY_INODE))
                return 0;

        /*
         * We need to lock here to prevent from producing dirty node pages
         * during the urgent cleaning time when runing out of free sections.
         */
        ilock = mutex_lock_op(sbi);
        ret = update_inode_page(inode);
        mutex_unlock_op(sbi, ilock);

        if (wbc)
                f2fs_balance_fs(sbi);

        return ret;
}

/*
 * Called at the last iput() if i_nlink is zero
 */
void f2fs_evict_inode(struct inode *inode)
{
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        int ilock;

        trace_f2fs_evict_inode(inode);
        truncate_inode_pages(&inode->i_data, 0);

        if (inode->i_ino == F2FS_NODE_INO(sbi) ||
                        inode->i_ino == F2FS_META_INO(sbi))
                goto no_delete;

        BUG_ON(atomic_read(&F2FS_I(inode)->dirty_dents));
        remove_dirty_dir_inode(inode);

        if (inode->i_nlink || is_bad_inode(inode))
                goto no_delete;

        sb_start_intwrite(inode->i_sb);
        set_inode_flag(F2FS_I(inode), FI_NO_ALLOC);
        i_size_write(inode, 0);

        if (F2FS_HAS_BLOCKS(inode))
                f2fs_truncate(inode);

        ilock = mutex_lock_op(sbi);
        remove_inode_page(inode);
        mutex_unlock_op(sbi, ilock);

        sb_end_intwrite(inode->i_sb);
no_delete:
        clear_inode(inode);
}