/*
 * fs/f2fs/file.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/stat.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include <linux/blkdev.h>
#include <linux/falloc.h>
#include <linux/types.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
#include <linux/mount.h>
#include <linux/pagevec.h>
#include <linux/uio.h>
#include <linux/uuid.h>
#include <linux/file.h>

#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "xattr.h"
#include "acl.h"
#include "gc.h"
#include "trace.h"
#include <trace/events/f2fs.h>

static int f2fs_filemap_fault(struct vm_fault *vmf)
{
        struct inode *inode = file_inode(vmf->vma->vm_file);
        int err;

        down_read(&F2FS_I(inode)->i_mmap_sem);
        err = filemap_fault(vmf);
        up_read(&F2FS_I(inode)->i_mmap_sem);

        return err;
}

static int f2fs_vm_page_mkwrite(struct vm_fault *vmf)
{
        struct page *page = vmf->page;
        struct inode *inode = file_inode(vmf->vma->vm_file);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct dnode_of_data dn;
        int err;

        if (unlikely(f2fs_cp_error(sbi))) {
                err = -EIO;
                goto err;
        }

        sb_start_pagefault(inode->i_sb);

        f2fs_bug_on(sbi, f2fs_has_inline_data(inode));

        /* block allocation */
        f2fs_lock_op(sbi);
        set_new_dnode(&dn, inode, NULL, NULL, 0);
        err = f2fs_reserve_block(&dn, page->index);
        if (err) {
                f2fs_unlock_op(sbi);
                goto out;
        }
        f2fs_put_dnode(&dn);
        f2fs_unlock_op(sbi);

        f2fs_balance_fs(sbi, dn.node_changed);

        file_update_time(vmf->vma->vm_file);
        down_read(&F2FS_I(inode)->i_mmap_sem);
        lock_page(page);
        if (unlikely(page->mapping != inode->i_mapping ||
                        page_offset(page) > i_size_read(inode) ||
                        !PageUptodate(page))) {
                unlock_page(page);
                err = -EFAULT;
                goto out_sem;
        }

        /*
         * check to see if the page is mapped already (no holes)
         */
        if (PageMappedToDisk(page))
                goto mapped;

        /* page is wholly or partially inside EOF */
        if (((loff_t)(page->index + 1) << PAGE_SHIFT) >
                                                i_size_read(inode)) {
                unsigned offset;
                offset = i_size_read(inode) & ~PAGE_MASK;
                zero_user_segment(page, offset, PAGE_SIZE);
        }
        set_page_dirty(page);
        if (!PageUptodate(page))
                SetPageUptodate(page);

        f2fs_update_iostat(sbi, APP_MAPPED_IO, F2FS_BLKSIZE);

        trace_f2fs_vm_page_mkwrite(page, DATA);
mapped:
        /* fill the page */
        f2fs_wait_on_page_writeback(page, DATA, false);

        /* wait for GCed encrypted page writeback */
        if (f2fs_encrypted_file(inode))
                f2fs_wait_on_block_writeback(sbi, dn.data_blkaddr);

out_sem:
        up_read(&F2FS_I(inode)->i_mmap_sem);
out:
        sb_end_pagefault(inode->i_sb);
        f2fs_update_time(sbi, REQ_TIME);
err:
        return block_page_mkwrite_return(err);
}

static const struct vm_operations_struct f2fs_file_vm_ops = {
        .fault          = f2fs_filemap_fault,
        .map_pages      = filemap_map_pages,
        .page_mkwrite   = f2fs_vm_page_mkwrite,
};

static int get_parent_ino(struct inode *inode, nid_t *pino)
{
        struct dentry *dentry;

        inode = igrab(inode);
        dentry = d_find_any_alias(inode);
        iput(inode);
        if (!dentry)
                return 0;

        *pino = parent_ino(dentry);
        dput(dentry);
        return 1;
}

static inline enum cp_reason_type need_do_checkpoint(struct inode *inode)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        enum cp_reason_type cp_reason = CP_NO_NEEDED;

        if (!S_ISREG(inode->i_mode))
                cp_reason = CP_NON_REGULAR;
        else if (inode->i_nlink != 1)
                cp_reason = CP_HARDLINK;
        else if (is_sbi_flag_set(sbi, SBI_NEED_CP))
                cp_reason = CP_SB_NEED_CP;
        else if (file_wrong_pino(inode))
                cp_reason = CP_WRONG_PINO;
        else if (!space_for_roll_forward(sbi))
                cp_reason = CP_NO_SPC_ROLL;
        else if (!is_checkpointed_node(sbi, F2FS_I(inode)->i_pino))
                cp_reason = CP_NODE_NEED_CP;
        else if (test_opt(sbi, FASTBOOT))
                cp_reason = CP_FASTBOOT_MODE;
        else if (sbi->active_logs == 2)
                cp_reason = CP_SPEC_LOG_NUM;
        else if (need_dentry_mark(sbi, inode->i_ino) &&
                exist_written_data(sbi, F2FS_I(inode)->i_pino, TRANS_DIR_INO))
                cp_reason = CP_RECOVER_DIR;

        return cp_reason;
}

static bool need_inode_page_update(struct f2fs_sb_info *sbi, nid_t ino)
{
        struct page *i = find_get_page(NODE_MAPPING(sbi), ino);
        bool ret = false;
        /* But we need to avoid that there are some inode updates */
        if ((i && PageDirty(i)) || need_inode_block_update(sbi, ino))
                ret = true;
        f2fs_put_page(i, 0);
        return ret;
}

static void try_to_fix_pino(struct inode *inode)
{
        struct f2fs_inode_info *fi = F2FS_I(inode);
        nid_t pino;

        down_write(&fi->i_sem);
        if (file_wrong_pino(inode) && inode->i_nlink == 1 &&
                        get_parent_ino(inode, &pino)) {
                f2fs_i_pino_write(inode, pino);
                file_got_pino(inode);
        }
        up_write(&fi->i_sem);
}

static int f2fs_do_sync_file(struct file *file, loff_t start, loff_t end,
                                                int datasync, bool atomic)
{
        struct inode *inode = file->f_mapping->host;
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        nid_t ino = inode->i_ino;
        int ret = 0;
        enum cp_reason_type cp_reason = 0;
        struct writeback_control wbc = {
                .sync_mode = WB_SYNC_ALL,
                .nr_to_write = LONG_MAX,
                .for_reclaim = 0,
        };

        if (unlikely(f2fs_readonly(inode->i_sb)))
                return 0;

        trace_f2fs_sync_file_enter(inode);

        /* if fdatasync is triggered, let's do in-place-update */
        if (datasync || get_dirty_pages(inode) <= SM_I(sbi)->min_fsync_blocks)
                set_inode_flag(inode, FI_NEED_IPU);
        ret = file_write_and_wait_range(file, start, end);
        clear_inode_flag(inode, FI_NEED_IPU);

        if (ret) {
                trace_f2fs_sync_file_exit(inode, cp_reason, datasync, ret);
                return ret;
        }

        /* if the inode is dirty, let's recover all the time */
        if (!f2fs_skip_inode_update(inode, datasync)) {
                f2fs_write_inode(inode, NULL);
                goto go_write;
        }

        /*
         * if there is no written data, don't waste time to write recovery info.
         */
        if (!is_inode_flag_set(inode, FI_APPEND_WRITE) &&
                        !exist_written_data(sbi, ino, APPEND_INO)) {

                /* it may call write_inode just prior to fsync */
                if (need_inode_page_update(sbi, ino))
                        goto go_write;

                if (is_inode_flag_set(inode, FI_UPDATE_WRITE) ||
                                exist_written_data(sbi, ino, UPDATE_INO))
                        goto flush_out;
                goto out;
        }
go_write:
        /*
         * Both of fdatasync() and fsync() are able to be recovered from
         * sudden-power-off.
         */
        down_read(&F2FS_I(inode)->i_sem);
        cp_reason = need_do_checkpoint(inode);
        up_read(&F2FS_I(inode)->i_sem);

        if (cp_reason) {
                /* all the dirty node pages should be flushed for POR */
                ret = f2fs_sync_fs(inode->i_sb, 1);

                /*
                 * We've secured consistency through sync_fs. Following pino
                 * will be used only for fsynced inodes after checkpoint.
                 */
                try_to_fix_pino(inode);
                clear_inode_flag(inode, FI_APPEND_WRITE);
                clear_inode_flag(inode, FI_UPDATE_WRITE);
                goto out;
        }
sync_nodes:
        ret = fsync_node_pages(sbi, inode, &wbc, atomic);
        if (ret)
                goto out;

        /* if cp_error was enabled, we should avoid infinite loop */
        if (unlikely(f2fs_cp_error(sbi))) {
                ret = -EIO;
                goto out;
        }

        if (need_inode_block_update(sbi, ino)) {
                f2fs_mark_inode_dirty_sync(inode, true);
                f2fs_write_inode(inode, NULL);
                goto sync_nodes;
        }

        /*
         * If it's atomic_write, it's just fine to keep write ordering. So
         * here we don't need to wait for node write completion, since we use
         * node chain which serializes node blocks. If one of node writes are
         * reordered, we can see simply broken chain, resulting in stopping
         * roll-forward recovery. It means we'll recover all or none node blocks
         * given fsync mark.
         */
        if (!atomic) {
                ret = wait_on_node_pages_writeback(sbi, ino);
                if (ret)
                        goto out;
        }

        /* once recovery info is written, don't need to tack this */
        remove_ino_entry(sbi, ino, APPEND_INO);
        clear_inode_flag(inode, FI_APPEND_WRITE);
flush_out:
        if (!atomic)
                ret = f2fs_issue_flush(sbi, inode->i_ino);
        if (!ret) {
                remove_ino_entry(sbi, ino, UPDATE_INO);
                clear_inode_flag(inode, FI_UPDATE_WRITE);
                remove_ino_entry(sbi, ino, FLUSH_INO);
        }
        f2fs_update_time(sbi, REQ_TIME);
out:
        trace_f2fs_sync_file_exit(inode, cp_reason, datasync, ret);
        f2fs_trace_ios(NULL, 1);
        return ret;
}

int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
{
        if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(file)))))
                return -EIO;
        return f2fs_do_sync_file(file, start, end, datasync, false);
}

static pgoff_t __get_first_dirty_index(struct address_space *mapping,
                                                pgoff_t pgofs, int whence)
{
        struct page *page;
        int nr_pages;

        if (whence != SEEK_DATA)
                return 0;

        /* find first dirty page index */
        nr_pages = find_get_pages_tag(mapping, &pgofs, PAGECACHE_TAG_DIRTY,
                                      1, &page);
        if (!nr_pages)
                return ULONG_MAX;
        pgofs = page->index;
        put_page(page);
        return pgofs;
}

static bool __found_offset(block_t blkaddr, pgoff_t dirty, pgoff_t pgofs,
                                                        int whence)
{
        switch (whence) {
        case SEEK_DATA:
                if ((blkaddr == NEW_ADDR && dirty == pgofs) ||
                        (blkaddr != NEW_ADDR && blkaddr != NULL_ADDR))
                        return true;
                break;
        case SEEK_HOLE:
                if (blkaddr == NULL_ADDR)
                        return true;
                break;
        }
        return false;
}

static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence)
{
        struct inode *inode = file->f_mapping->host;
        loff_t maxbytes = inode->i_sb->s_maxbytes;
        struct dnode_of_data dn;
        pgoff_t pgofs, end_offset, dirty;
        loff_t data_ofs = offset;
        loff_t isize;
        int err = 0;

        inode_lock(inode);

        isize = i_size_read(inode);
        if (offset >= isize)
                goto fail;

        /* handle inline data case */
        if (f2fs_has_inline_data(inode) || f2fs_has_inline_dentry(inode)) {
                if (whence == SEEK_HOLE)
                        data_ofs = isize;
                goto found;
        }

        pgofs = (pgoff_t)(offset >> PAGE_SHIFT);

        dirty = __get_first_dirty_index(inode->i_mapping, pgofs, whence);

        for (; data_ofs < isize; data_ofs = (loff_t)pgofs << PAGE_SHIFT) {
                set_new_dnode(&dn, inode, NULL, NULL, 0);
                err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE);
                if (err && err != -ENOENT) {
                        goto fail;
                } else if (err == -ENOENT) {
                        /* direct node does not exists */
                        if (whence == SEEK_DATA) {
                                pgofs = get_next_page_offset(&dn, pgofs);
                                continue;
                        } else {
                                goto found;
                        }
                }

                end_offset = ADDRS_PER_PAGE(dn.node_page, inode);

                /* find data/hole in dnode block */
                for (; dn.ofs_in_node < end_offset;
                                dn.ofs_in_node++, pgofs++,
                                data_ofs = (loff_t)pgofs << PAGE_SHIFT) {
                        block_t blkaddr;
                        blkaddr = datablock_addr(dn.inode,
                                        dn.node_page, dn.ofs_in_node);

                        if (__found_offset(blkaddr, dirty, pgofs, whence)) {
                                f2fs_put_dnode(&dn);
                                goto found;
                        }
                }
                f2fs_put_dnode(&dn);
        }

        if (whence == SEEK_DATA)
                goto fail;
found:
        if (whence == SEEK_HOLE && data_ofs > isize)
                data_ofs = isize;
        inode_unlock(inode);
        return vfs_setpos(file, data_ofs, maxbytes);
fail:
        inode_unlock(inode);
        return -ENXIO;
}

static loff_t f2fs_llseek(struct file *file, loff_t offset, int whence)
{
        struct inode *inode = file->f_mapping->host;
        loff_t maxbytes = inode->i_sb->s_maxbytes;

        switch (whence) {
        case SEEK_SET:
        case SEEK_CUR:
        case SEEK_END:
                return generic_file_llseek_size(file, offset, whence,
                                                maxbytes, i_size_read(inode));
        case SEEK_DATA:
        case SEEK_HOLE:
                if (offset < 0)
                        return -ENXIO;
                return f2fs_seek_block(file, offset, whence);
        }

        return -EINVAL;
}

static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
        struct inode *inode = file_inode(file);
        int err;

        if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
                return -EIO;

        /* we don't need to use inline_data strictly */
        err = f2fs_convert_inline_inode(inode);
        if (err)
                return err;

        file_accessed(file);
        vma->vm_ops = &f2fs_file_vm_ops;
        return 0;
}

static int f2fs_file_open(struct inode *inode, struct file *filp)
{
        int err = fscrypt_file_open(inode, filp);

        if (err)
                return err;
        return dquot_file_open(inode, filp);
}

void truncate_data_blocks_range(struct dnode_of_data *dn, int count)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
        struct f2fs_node *raw_node;
        int nr_free = 0, ofs = dn->ofs_in_node, len = count;
        __le32 *addr;
        int base = 0;

        if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))
                base = get_extra_isize(dn->inode);

        raw_node = F2FS_NODE(dn->node_page);
        addr = blkaddr_in_node(raw_node) + base + ofs;

        for (; count > 0; count--, addr++, dn->ofs_in_node++) {
                block_t blkaddr = le32_to_cpu(*addr);
                if (blkaddr == NULL_ADDR)
                        continue;

                dn->data_blkaddr = NULL_ADDR;
                set_data_blkaddr(dn);
                invalidate_blocks(sbi, blkaddr);
                if (dn->ofs_in_node == 0 && IS_INODE(dn->node_page))
                        clear_inode_flag(dn->inode, FI_FIRST_BLOCK_WRITTEN);
                nr_free++;
        }

        if (nr_free) {
                pgoff_t fofs;
                /*
                 * once we invalidate valid blkaddr in range [ofs, ofs + count],
                 * we will invalidate all blkaddr in the whole range.
                 */
                fofs = start_bidx_of_node(ofs_of_node(dn->node_page),
                                                        dn->inode) + ofs;
                f2fs_update_extent_cache_range(dn, fofs, 0, len);
                dec_valid_block_count(sbi, dn->inode, nr_free);
        }
        dn->ofs_in_node = ofs;

        f2fs_update_time(sbi, REQ_TIME);
        trace_f2fs_truncate_data_blocks_range(dn->inode, dn->nid,
                                         dn->ofs_in_node, nr_free);
}

void truncate_data_blocks(struct dnode_of_data *dn)
{
        truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
}

static int truncate_partial_data_page(struct inode *inode, u64 from,
                                                                bool cache_only)
{
        unsigned offset = from & (PAGE_SIZE - 1);
        pgoff_t index = from >> PAGE_SHIFT;
        struct address_space *mapping = inode->i_mapping;
        struct page *page;

        if (!offset && !cache_only)
                return 0;

        if (cache_only) {
                page = find_lock_page(mapping, index);
                if (page && PageUptodate(page))
                        goto truncate_out;
                f2fs_put_page(page, 1);
                return 0;
        }

        page = get_lock_data_page(inode, index, true);
        if (IS_ERR(page))
                return PTR_ERR(page) == -ENOENT ? 0 : PTR_ERR(page);
truncate_out:
        f2fs_wait_on_page_writeback(page, DATA, true);
        zero_user(page, offset, PAGE_SIZE - offset);

        /* An encrypted inode should have a key and truncate the last page. */
        f2fs_bug_on(F2FS_I_SB(inode), cache_only && f2fs_encrypted_inode(inode));
        if (!cache_only)
                set_page_dirty(page);
        f2fs_put_page(page, 1);
        return 0;
}

int truncate_blocks(struct inode *inode, u64 from, bool lock)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        unsigned int blocksize = inode->i_sb->s_blocksize;
        struct dnode_of_data dn;
        pgoff_t free_from;
        int count = 0, err = 0;
        struct page *ipage;
        bool truncate_page = false;

        trace_f2fs_truncate_blocks_enter(inode, from);

        free_from = (pgoff_t)F2FS_BYTES_TO_BLK(from + blocksize - 1);

        if (free_from >= sbi->max_file_blocks)
                goto free_partial;

        if (lock)
                f2fs_lock_op(sbi);

        ipage = get_node_page(sbi, inode->i_ino);
        if (IS_ERR(ipage)) {
                err = PTR_ERR(ipage);
                goto out;
        }

        if (f2fs_has_inline_data(inode)) {
                truncate_inline_inode(inode, ipage, from);
                f2fs_put_page(ipage, 1);
                truncate_page = true;
                goto out;
        }

        set_new_dnode(&dn, inode, ipage, NULL, 0);
        err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE_RA);
        if (err) {
                if (err == -ENOENT)
                        goto free_next;
                goto out;
        }

        count = ADDRS_PER_PAGE(dn.node_page, inode);

        count -= dn.ofs_in_node;
        f2fs_bug_on(sbi, count < 0);

        if (dn.ofs_in_node || IS_INODE(dn.node_page)) {
                truncate_data_blocks_range(&dn, count);
                free_from += count;
        }

        f2fs_put_dnode(&dn);
free_next:
        err = truncate_inode_blocks(inode, free_from);
out:
        if (lock)
                f2fs_unlock_op(sbi);
free_partial:
        /* lastly zero out the first data page */
        if (!err)
                err = truncate_partial_data_page(inode, from, truncate_page);

        trace_f2fs_truncate_blocks_exit(inode, err);
        return err;
}

int f2fs_truncate(struct inode *inode)
{
        int err;

        if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
                return -EIO;

        if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
                                S_ISLNK(inode->i_mode)))
                return 0;

        trace_f2fs_truncate(inode);

#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(F2FS_I_SB(inode), FAULT_TRUNCATE)) {
                f2fs_show_injection_info(FAULT_TRUNCATE);
                return -EIO;
        }
#endif
        /* we should check inline_data size */
        if (!f2fs_may_inline_data(inode)) {
                err = f2fs_convert_inline_inode(inode);
                if (err)
                        return err;
        }

        err = truncate_blocks(inode, i_size_read(inode), true);
        if (err)
                return err;

        inode->i_mtime = inode->i_ctime = current_time(inode);
        f2fs_mark_inode_dirty_sync(inode, false);
        return 0;
}

int f2fs_getattr(const struct path *path, struct kstat *stat,
                 u32 request_mask, unsigned int query_flags)
{
        struct inode *inode = d_inode(path->dentry);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct f2fs_inode *ri;
        unsigned int flags;

        if (f2fs_has_extra_attr(inode) &&
                        f2fs_sb_has_inode_crtime(inode->i_sb) &&
                        F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_crtime)) {
                stat->result_mask |= STATX_BTIME;
                stat->btime.tv_sec = fi->i_crtime.tv_sec;
                stat->btime.tv_nsec = fi->i_crtime.tv_nsec;
        }

        flags = fi->i_flags & (FS_FL_USER_VISIBLE | FS_PROJINHERIT_FL);
        if (flags & FS_APPEND_FL)
                stat->attributes |= STATX_ATTR_APPEND;
        if (flags & FS_COMPR_FL)
                stat->attributes |= STATX_ATTR_COMPRESSED;
        if (f2fs_encrypted_inode(inode))
                stat->attributes |= STATX_ATTR_ENCRYPTED;
        if (flags & FS_IMMUTABLE_FL)
                stat->attributes |= STATX_ATTR_IMMUTABLE;
        if (flags & FS_NODUMP_FL)
                stat->attributes |= STATX_ATTR_NODUMP;

        stat->attributes_mask |= (STATX_ATTR_APPEND |
                                  STATX_ATTR_COMPRESSED |
                                  STATX_ATTR_ENCRYPTED |
                                  STATX_ATTR_IMMUTABLE |
                                  STATX_ATTR_NODUMP);

        generic_fillattr(inode, stat);

        /* we need to show initial sectors used for inline_data/dentries */
        if ((S_ISREG(inode->i_mode) && f2fs_has_inline_data(inode)) ||
                                        f2fs_has_inline_dentry(inode))
                stat->blocks += (stat->size + 511) >> 9;

        return 0;
}

#ifdef CONFIG_F2FS_FS_POSIX_ACL
static void __setattr_copy(struct inode *inode, const struct iattr *attr)
{
        unsigned int ia_valid = attr->ia_valid;

        if (ia_valid & ATTR_UID)
                inode->i_uid = attr->ia_uid;
        if (ia_valid & ATTR_GID)
                inode->i_gid = attr->ia_gid;
        if (ia_valid & ATTR_ATIME)
                inode->i_atime = timespec_trunc(attr->ia_atime,
                                                inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_MTIME)
                inode->i_mtime = timespec_trunc(attr->ia_mtime,
                                                inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_CTIME)
                inode->i_ctime = timespec_trunc(attr->ia_ctime,
                                                inode->i_sb->s_time_gran);
        if (ia_valid & ATTR_MODE) {
                umode_t mode = attr->ia_mode;

                if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
                        mode &= ~S_ISGID;
                set_acl_inode(inode, mode);
        }
}
#else
#define __setattr_copy setattr_copy
#endif

int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
{
        struct inode *inode = d_inode(dentry);
        int err;
        bool size_changed = false;

        if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
                return -EIO;

        err = setattr_prepare(dentry, attr);
        if (err)
                return err;

        err = fscrypt_prepare_setattr(dentry, attr);
        if (err)
                return err;

        if (is_quota_modification(inode, attr)) {
                err = dquot_initialize(inode);
                if (err)
                        return err;
        }
        if ((attr->ia_valid & ATTR_UID &&
                !uid_eq(attr->ia_uid, inode->i_uid)) ||
                (attr->ia_valid & ATTR_GID &&
                !gid_eq(attr->ia_gid, inode->i_gid))) {
                err = dquot_transfer(inode, attr);
                if (err)
                        return err;
        }

        if (attr->ia_valid & ATTR_SIZE) {
                if (attr->ia_size <= i_size_read(inode)) {
                        down_write(&F2FS_I(inode)->i_mmap_sem);
                        truncate_setsize(inode, attr->ia_size);
                        err = f2fs_truncate(inode);
                        up_write(&F2FS_I(inode)->i_mmap_sem);
                        if (err)
                                return err;
                } else {
                        /*
                         * do not trim all blocks after i_size if target size is
                         * larger than i_size.
                         */
                        down_write(&F2FS_I(inode)->i_mmap_sem);
                        truncate_setsize(inode, attr->ia_size);
                        up_write(&F2FS_I(inode)->i_mmap_sem);

                        /* should convert inline inode here */
                        if (!f2fs_may_inline_data(inode)) {
                                err = f2fs_convert_inline_inode(inode);
                                if (err)
                                        return err;
                        }
                        inode->i_mtime = inode->i_ctime = current_time(inode);
                }

                down_write(&F2FS_I(inode)->i_sem);
                F2FS_I(inode)->last_disk_size = i_size_read(inode);
                up_write(&F2FS_I(inode)->i_sem);

                size_changed = true;
        }

        __setattr_copy(inode, attr);

        if (attr->ia_valid & ATTR_MODE) {
                err = posix_acl_chmod(inode, get_inode_mode(inode));
                if (err || is_inode_flag_set(inode, FI_ACL_MODE)) {
                        inode->i_mode = F2FS_I(inode)->i_acl_mode;
                        clear_inode_flag(inode, FI_ACL_MODE);
                }
        }

        /* file size may changed here */
        f2fs_mark_inode_dirty_sync(inode, size_changed);

        /* inode change will produce dirty node pages flushed by checkpoint */
        f2fs_balance_fs(F2FS_I_SB(inode), true);

        return err;
}

const struct inode_operations f2fs_file_inode_operations = {
        .getattr        = f2fs_getattr,
        .setattr        = f2fs_setattr,
        .get_acl        = f2fs_get_acl,
        .set_acl        = f2fs_set_acl,
#ifdef CONFIG_F2FS_FS_XATTR
        .listxattr      = f2fs_listxattr,
#endif
        .fiemap         = f2fs_fiemap,
};

static int fill_zero(struct inode *inode, pgoff_t index,
                                        loff_t start, loff_t len)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct page *page;

        if (!len)
                return 0;

        f2fs_balance_fs(sbi, true);

        f2fs_lock_op(sbi);
        page = get_new_data_page(inode, NULL, index, false);
        f2fs_unlock_op(sbi);

        if (IS_ERR(page))
                return PTR_ERR(page);

        f2fs_wait_on_page_writeback(page, DATA, true);
        zero_user(page, start, len);
        set_page_dirty(page);
        f2fs_put_page(page, 1);
        return 0;
}

int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
{
        int err;

        while (pg_start < pg_end) {
                struct dnode_of_data dn;
                pgoff_t end_offset, count;

                set_new_dnode(&dn, inode, NULL, NULL, 0);
                err = get_dnode_of_data(&dn, pg_start, LOOKUP_NODE);
                if (err) {
                        if (err == -ENOENT) {
                                pg_start = get_next_page_offset(&dn, pg_start);
                                continue;
                        }
                        return err;
                }

                end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
                count = min(end_offset - dn.ofs_in_node, pg_end - pg_start);

                f2fs_bug_on(F2FS_I_SB(inode), count == 0 || count > end_offset);

                truncate_data_blocks_range(&dn, count);
                f2fs_put_dnode(&dn);

                pg_start += count;
        }
        return 0;
}

static int punch_hole(struct inode *inode, loff_t offset, loff_t len)
{
        pgoff_t pg_start, pg_end;
        loff_t off_start, off_end;
        int ret;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                return ret;

        pg_start = ((unsigned long long) offset) >> PAGE_SHIFT;
        pg_end = ((unsigned long long) offset + len) >> PAGE_SHIFT;

        off_start = offset & (PAGE_SIZE - 1);
        off_end = (offset + len) & (PAGE_SIZE - 1);

        if (pg_start == pg_end) {
                ret = fill_zero(inode, pg_start, off_start,
                                                off_end - off_start);
                if (ret)
                        return ret;
        } else {
                if (off_start) {
                        ret = fill_zero(inode, pg_start++, off_start,
                                                PAGE_SIZE - off_start);
                        if (ret)
                                return ret;
                }
                if (off_end) {
                        ret = fill_zero(inode, pg_end, 0, off_end);
                        if (ret)
                                return ret;
                }

                if (pg_start < pg_end) {
                        struct address_space *mapping = inode->i_mapping;
                        loff_t blk_start, blk_end;
                        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

                        f2fs_balance_fs(sbi, true);

                        blk_start = (loff_t)pg_start << PAGE_SHIFT;
                        blk_end = (loff_t)pg_end << PAGE_SHIFT;
                        down_write(&F2FS_I(inode)->i_mmap_sem);
                        truncate_inode_pages_range(mapping, blk_start,
                                        blk_end - 1);

                        f2fs_lock_op(sbi);
                        ret = truncate_hole(inode, pg_start, pg_end);
                        f2fs_unlock_op(sbi);
                        up_write(&F2FS_I(inode)->i_mmap_sem);
                }
        }

        return ret;
}

static int __read_out_blkaddrs(struct inode *inode, block_t *blkaddr,
                                int *do_replace, pgoff_t off, pgoff_t len)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct dnode_of_data dn;
        int ret, done, i;

next_dnode:
        set_new_dnode(&dn, inode, NULL, NULL, 0);
        ret = get_dnode_of_data(&dn, off, LOOKUP_NODE_RA);
        if (ret && ret != -ENOENT) {
                return ret;
        } else if (ret == -ENOENT) {
                if (dn.max_level == 0)
                        return -ENOENT;
                done = min((pgoff_t)ADDRS_PER_BLOCK - dn.ofs_in_node, len);
                blkaddr += done;
                do_replace += done;
                goto next;
        }

        done = min((pgoff_t)ADDRS_PER_PAGE(dn.node_page, inode) -
                                                        dn.ofs_in_node, len);
        for (i = 0; i < done; i++, blkaddr++, do_replace++, dn.ofs_in_node++) {
                *blkaddr = datablock_addr(dn.inode,
                                        dn.node_page, dn.ofs_in_node);
                if (!is_checkpointed_data(sbi, *blkaddr)) {

                        if (test_opt(sbi, LFS)) {
                                f2fs_put_dnode(&dn);
                                return -ENOTSUPP;
                        }

                        /* do not invalidate this block address */
                        f2fs_update_data_blkaddr(&dn, NULL_ADDR);
                        *do_replace = 1;
                }
        }
        f2fs_put_dnode(&dn);
next:
        len -= done;
        off += done;
        if (len)
                goto next_dnode;
        return 0;
}

static int __roll_back_blkaddrs(struct inode *inode, block_t *blkaddr,
                                int *do_replace, pgoff_t off, int len)
{

        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct dnode_of_data dn;
        int ret, i;

        for (i = 0; i < len; i++, do_replace++, blkaddr++) {
                if (*do_replace == 0)
                        continue;

                set_new_dnode(&dn, inode, NULL, NULL, 0);
                ret = get_dnode_of_data(&dn, off + i, LOOKUP_NODE_RA);
                if (ret) {
                        dec_valid_block_count(sbi, inode, 1);
                        invalidate_blocks(sbi, *blkaddr);
                } else {
                        f2fs_update_data_blkaddr(&dn, *blkaddr);
                }
                f2fs_put_dnode(&dn);
        }
        return 0;
}

static int __clone_blkaddrs(struct inode *src_inode, struct inode *dst_inode,
                        block_t *blkaddr, int *do_replace,
                        pgoff_t src, pgoff_t dst, pgoff_t len, bool full)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(src_inode);
        pgoff_t i = 0;
        int ret;

        while (i < len) {
                if (blkaddr[i] == NULL_ADDR && !full) {
                        i++;
                        continue;
                }

                if (do_replace[i] || blkaddr[i] == NULL_ADDR) {
                        struct dnode_of_data dn;
                        struct node_info ni;
                        size_t new_size;
                        pgoff_t ilen;

                        set_new_dnode(&dn, dst_inode, NULL, NULL, 0);
                        ret = get_dnode_of_data(&dn, dst + i, ALLOC_NODE);
                        if (ret)
                                return ret;

                        get_node_info(sbi, dn.nid, &ni);
                        ilen = min((pgoff_t)
                                ADDRS_PER_PAGE(dn.node_page, dst_inode) -
                                                dn.ofs_in_node, len - i);
                        do {
                                dn.data_blkaddr = datablock_addr(dn.inode,
                                                dn.node_page, dn.ofs_in_node);
                                truncate_data_blocks_range(&dn, 1);

                                if (do_replace[i]) {
                                        f2fs_i_blocks_write(src_inode,
                                                        1, false, false);
                                        f2fs_i_blocks_write(dst_inode,
                                                        1, true, false);
                                        f2fs_replace_block(sbi, &dn, dn.data_blkaddr,
                                        blkaddr[i], ni.version, true, false);

                                        do_replace[i] = 0;
                                }
                                dn.ofs_in_node++;
                                i++;
                                new_size = (dst + i) << PAGE_SHIFT;
                                if (dst_inode->i_size < new_size)
                                        f2fs_i_size_write(dst_inode, new_size);
                        } while (--ilen && (do_replace[i] || blkaddr[i] == NULL_ADDR));

                        f2fs_put_dnode(&dn);
                } else {
                        struct page *psrc, *pdst;

                        psrc = get_lock_data_page(src_inode, src + i, true);
                        if (IS_ERR(psrc))
                                return PTR_ERR(psrc);
                        pdst = get_new_data_page(dst_inode, NULL, dst + i,
                                                                true);
                        if (IS_ERR(pdst)) {
                                f2fs_put_page(psrc, 1);
                                return PTR_ERR(pdst);
                        }
                        f2fs_copy_page(psrc, pdst);
                        set_page_dirty(pdst);
                        f2fs_put_page(pdst, 1);
                        f2fs_put_page(psrc, 1);

                        ret = truncate_hole(src_inode, src + i, src + i + 1);
                        if (ret)
                                return ret;
                        i++;
                }
        }
        return 0;
}

static int __exchange_data_block(struct inode *src_inode,
                        struct inode *dst_inode, pgoff_t src, pgoff_t dst,
                        pgoff_t len, bool full)
{
        block_t *src_blkaddr;
        int *do_replace;
        pgoff_t olen;
        int ret;

        while (len) {
                olen = min((pgoff_t)4 * ADDRS_PER_BLOCK, len);

                src_blkaddr = f2fs_kvzalloc(F2FS_I_SB(src_inode),
                                        sizeof(block_t) * olen, GFP_KERNEL);
                if (!src_blkaddr)
                        return -ENOMEM;

                do_replace = f2fs_kvzalloc(F2FS_I_SB(src_inode),
                                        sizeof(int) * olen, GFP_KERNEL);
                if (!do_replace) {
                        kvfree(src_blkaddr);
                        return -ENOMEM;
                }

                ret = __read_out_blkaddrs(src_inode, src_blkaddr,
                                        do_replace, src, olen);
                if (ret)
                        goto roll_back;

                ret = __clone_blkaddrs(src_inode, dst_inode, src_blkaddr,
                                        do_replace, src, dst, olen, full);
                if (ret)
                        goto roll_back;

                src += olen;
                dst += olen;
                len -= olen;

                kvfree(src_blkaddr);
                kvfree(do_replace);
        }
        return 0;

roll_back:
        __roll_back_blkaddrs(src_inode, src_blkaddr, do_replace, src, len);
        kvfree(src_blkaddr);
        kvfree(do_replace);
        return ret;
}

static int f2fs_do_collapse(struct inode *inode, pgoff_t start, pgoff_t end)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        pgoff_t nrpages = (i_size_read(inode) + PAGE_SIZE - 1) / PAGE_SIZE;
        int ret;

        f2fs_balance_fs(sbi, true);
        f2fs_lock_op(sbi);

        f2fs_drop_extent_tree(inode);

        ret = __exchange_data_block(inode, inode, end, start, nrpages - end, true);
        f2fs_unlock_op(sbi);
        return ret;
}

static int f2fs_collapse_range(struct inode *inode, loff_t offset, loff_t len)
{
        pgoff_t pg_start, pg_end;
        loff_t new_size;
        int ret;

        if (offset + len >= i_size_read(inode))
                return -EINVAL;

        /* collapse range should be aligned to block size of f2fs. */
        if (offset & (F2FS_BLKSIZE - 1) || len & (F2FS_BLKSIZE - 1))
                return -EINVAL;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                return ret;

        pg_start = offset >> PAGE_SHIFT;
        pg_end = (offset + len) >> PAGE_SHIFT;

        /* avoid gc operation during block exchange */
        down_write(&F2FS_I(inode)->dio_rwsem[WRITE]);

        down_write(&F2FS_I(inode)->i_mmap_sem);
        /* write out all dirty pages from offset */
        ret = filemap_write_and_wait_range(inode->i_mapping, offset, LLONG_MAX);
        if (ret)
                goto out_unlock;

        truncate_pagecache(inode, offset);

        ret = f2fs_do_collapse(inode, pg_start, pg_end);
        if (ret)
                goto out_unlock;

        /* write out all moved pages, if possible */
        filemap_write_and_wait_range(inode->i_mapping, offset, LLONG_MAX);
        truncate_pagecache(inode, offset);

        new_size = i_size_read(inode) - len;
        truncate_pagecache(inode, new_size);

        ret = truncate_blocks(inode, new_size, true);
        if (!ret)
                f2fs_i_size_write(inode, new_size);
out_unlock:
        up_write(&F2FS_I(inode)->i_mmap_sem);
        up_write(&F2FS_I(inode)->dio_rwsem[WRITE]);
        return ret;
}

static int f2fs_do_zero_range(struct dnode_of_data *dn, pgoff_t start,
                                                                pgoff_t end)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
        pgoff_t index = start;
        unsigned int ofs_in_node = dn->ofs_in_node;
        blkcnt_t count = 0;
        int ret;

        for (; index < end; index++, dn->ofs_in_node++) {
                if (datablock_addr(dn->inode, dn->node_page,
                                        dn->ofs_in_node) == NULL_ADDR)
                        count++;
        }

        dn->ofs_in_node = ofs_in_node;
        ret = reserve_new_blocks(dn, count);
        if (ret)
                return ret;

        dn->ofs_in_node = ofs_in_node;
        for (index = start; index < end; index++, dn->ofs_in_node++) {
                dn->data_blkaddr = datablock_addr(dn->inode,
                                        dn->node_page, dn->ofs_in_node);
                /*
                 * reserve_new_blocks will not guarantee entire block
                 * allocation.
                 */
                if (dn->data_blkaddr == NULL_ADDR) {
                        ret = -ENOSPC;
                        break;
                }
                if (dn->data_blkaddr != NEW_ADDR) {
                        invalidate_blocks(sbi, dn->data_blkaddr);
                        dn->data_blkaddr = NEW_ADDR;
                        set_data_blkaddr(dn);
                }
        }

        f2fs_update_extent_cache_range(dn, start, 0, index - start);

        return ret;
}

static int f2fs_zero_range(struct inode *inode, loff_t offset, loff_t len,
                                                                int mode)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct address_space *mapping = inode->i_mapping;
        pgoff_t index, pg_start, pg_end;
        loff_t new_size = i_size_read(inode);
        loff_t off_start, off_end;
        int ret = 0;

        ret = inode_newsize_ok(inode, (len + offset));
        if (ret)
                return ret;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                return ret;

        down_write(&F2FS_I(inode)->i_mmap_sem);
        ret = filemap_write_and_wait_range(mapping, offset, offset + len - 1);
        if (ret)
                goto out_sem;

        truncate_pagecache_range(inode, offset, offset + len - 1);

        pg_start = ((unsigned long long) offset) >> PAGE_SHIFT;
        pg_end = ((unsigned long long) offset + len) >> PAGE_SHIFT;

        off_start = offset & (PAGE_SIZE - 1);
        off_end = (offset + len) & (PAGE_SIZE - 1);

        if (pg_start == pg_end) {
                ret = fill_zero(inode, pg_start, off_start,
                                                off_end - off_start);
                if (ret)
                        goto out_sem;

                new_size = max_t(loff_t, new_size, offset + len);
        } else {
                if (off_start) {
                        ret = fill_zero(inode, pg_start++, off_start,
                                                PAGE_SIZE - off_start);
                        if (ret)
                                goto out_sem;

                        new_size = max_t(loff_t, new_size,
                                        (loff_t)pg_start << PAGE_SHIFT);
                }

                for (index = pg_start; index < pg_end;) {
                        struct dnode_of_data dn;
                        unsigned int end_offset;
                        pgoff_t end;

                        f2fs_lock_op(sbi);

                        set_new_dnode(&dn, inode, NULL, NULL, 0);
                        ret = get_dnode_of_data(&dn, index, ALLOC_NODE);
                        if (ret) {
                                f2fs_unlock_op(sbi);
                                goto out;
                        }

                        end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
                        end = min(pg_end, end_offset - dn.ofs_in_node + index);

                        ret = f2fs_do_zero_range(&dn, index, end);
                        f2fs_put_dnode(&dn);
                        f2fs_unlock_op(sbi);

                        f2fs_balance_fs(sbi, dn.node_changed);

                        if (ret)
                                goto out;

                        index = end;
                        new_size = max_t(loff_t, new_size,
                                        (loff_t)index << PAGE_SHIFT);
                }

                if (off_end) {
                        ret = fill_zero(inode, pg_end, 0, off_end);
                        if (ret)
                                goto out;

                        new_size = max_t(loff_t, new_size, offset + len);
                }
        }

out:
        if (!(mode & FALLOC_FL_KEEP_SIZE) && i_size_read(inode) < new_size)
                f2fs_i_size_write(inode, new_size);
out_sem:
        up_write(&F2FS_I(inode)->i_mmap_sem);

        return ret;
}

static int f2fs_insert_range(struct inode *inode, loff_t offset, loff_t len)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        pgoff_t nr, pg_start, pg_end, delta, idx;
        loff_t new_size;
        int ret = 0;

        new_size = i_size_read(inode) + len;
        ret = inode_newsize_ok(inode, new_size);
        if (ret)
                return ret;

        if (offset >= i_size_read(inode))
                return -EINVAL;

        /* insert range should be aligned to block size of f2fs. */
        if (offset & (F2FS_BLKSIZE - 1) || len & (F2FS_BLKSIZE - 1))
                return -EINVAL;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                return ret;

        f2fs_balance_fs(sbi, true);

        /* avoid gc operation during block exchange */
        down_write(&F2FS_I(inode)->dio_rwsem[WRITE]);

        down_write(&F2FS_I(inode)->i_mmap_sem);
        ret = truncate_blocks(inode, i_size_read(inode), true);
        if (ret)
                goto out;

        /* write out all dirty pages from offset */
        ret = filemap_write_and_wait_range(inode->i_mapping, offset, LLONG_MAX);
        if (ret)
                goto out;

        truncate_pagecache(inode, offset);

        pg_start = offset >> PAGE_SHIFT;
        pg_end = (offset + len) >> PAGE_SHIFT;
        delta = pg_end - pg_start;
        idx = (i_size_read(inode) + PAGE_SIZE - 1) / PAGE_SIZE;

        while (!ret && idx > pg_start) {
                nr = idx - pg_start;
                if (nr > delta)
                        nr = delta;
                idx -= nr;

                f2fs_lock_op(sbi);
                f2fs_drop_extent_tree(inode);

                ret = __exchange_data_block(inode, inode, idx,
                                        idx + delta, nr, false);
                f2fs_unlock_op(sbi);
        }

        /* write out all moved pages, if possible */
        filemap_write_and_wait_range(inode->i_mapping, offset, LLONG_MAX);
        truncate_pagecache(inode, offset);

        if (!ret)
                f2fs_i_size_write(inode, new_size);
out:
        up_write(&F2FS_I(inode)->i_mmap_sem);
        up_write(&F2FS_I(inode)->dio_rwsem[WRITE]);
        return ret;
}

static int expand_inode_data(struct inode *inode, loff_t offset,
                                        loff_t len, int mode)
{
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct f2fs_map_blocks map = { .m_next_pgofs = NULL,
                        .m_next_extent = NULL, .m_seg_type = NO_CHECK_TYPE };
        pgoff_t pg_end;
        loff_t new_size = i_size_read(inode);
        loff_t off_end;
        int err;

        err = inode_newsize_ok(inode, (len + offset));
        if (err)
                return err;

        err = f2fs_convert_inline_inode(inode);
        if (err)
                return err;

        f2fs_balance_fs(sbi, true);

        pg_end = ((unsigned long long)offset + len) >> PAGE_SHIFT;
        off_end = (offset + len) & (PAGE_SIZE - 1);

        map.m_lblk = ((unsigned long long)offset) >> PAGE_SHIFT;
        map.m_len = pg_end - map.m_lblk;
        if (off_end)
                map.m_len++;

        err = f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_AIO);
        if (err) {
                pgoff_t last_off;

                if (!map.m_len)
                        return err;

                last_off = map.m_lblk + map.m_len - 1;

                /* update new size to the failed position */
                new_size = (last_off == pg_end) ? offset + len:
                                        (loff_t)(last_off + 1) << PAGE_SHIFT;
        } else {
                new_size = ((loff_t)pg_end << PAGE_SHIFT) + off_end;
        }

        if (new_size > i_size_read(inode)) {
                if (mode & FALLOC_FL_KEEP_SIZE)
                        file_set_keep_isize(inode);
                else
                        f2fs_i_size_write(inode, new_size);
        }

        return err;
}

static long f2fs_fallocate(struct file *file, int mode,
                                loff_t offset, loff_t len)
{
        struct inode *inode = file_inode(file);
        long ret = 0;

        if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
                return -EIO;

        /* f2fs only support ->fallocate for regular file */
        if (!S_ISREG(inode->i_mode))
                return -EINVAL;

        if (f2fs_encrypted_inode(inode) &&
                (mode & (FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_INSERT_RANGE)))
                return -EOPNOTSUPP;

        if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
                        FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE |
                        FALLOC_FL_INSERT_RANGE))
                return -EOPNOTSUPP;

        inode_lock(inode);

        if (mode & FALLOC_FL_PUNCH_HOLE) {
                if (offset >= inode->i_size)
                        goto out;

                ret = punch_hole(inode, offset, len);
        } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
                ret = f2fs_collapse_range(inode, offset, len);
        } else if (mode & FALLOC_FL_ZERO_RANGE) {
                ret = f2fs_zero_range(inode, offset, len, mode);
        } else if (mode & FALLOC_FL_INSERT_RANGE) {
                ret = f2fs_insert_range(inode, offset, len);
        } else {
                ret = expand_inode_data(inode, offset, len, mode);
        }

        if (!ret) {
                inode->i_mtime = inode->i_ctime = current_time(inode);
                f2fs_mark_inode_dirty_sync(inode, false);
                f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
        }

out:
        inode_unlock(inode);

        trace_f2fs_fallocate(inode, mode, offset, len, ret);
        return ret;
}

static int f2fs_release_file(struct inode *inode, struct file *filp)
{
        /*
         * f2fs_relase_file is called at every close calls. So we should
         * not drop any inmemory pages by close called by other process.
         */
        if (!(filp->f_mode & FMODE_WRITE) ||
                        atomic_read(&inode->i_writecount) != 1)
                return 0;

        /* some remained atomic pages should discarded */
        if (f2fs_is_atomic_file(inode))
                drop_inmem_pages(inode);
        if (f2fs_is_volatile_file(inode)) {
                clear_inode_flag(inode, FI_VOLATILE_FILE);
                stat_dec_volatile_write(inode);
                set_inode_flag(inode, FI_DROP_CACHE);
                filemap_fdatawrite(inode->i_mapping);
                clear_inode_flag(inode, FI_DROP_CACHE);
        }
        return 0;
}

static int f2fs_file_flush(struct file *file, fl_owner_t id)
{
        struct inode *inode = file_inode(file);

        /*
         * If the process doing a transaction is crashed, we should do
         * roll-back. Otherwise, other reader/write can see corrupted database
         * until all the writers close its file. Since this should be done
         * before dropping file lock, it needs to do in ->flush.
         */
        if (f2fs_is_atomic_file(inode) &&
                        F2FS_I(inode)->inmem_task == current)
                drop_inmem_pages(inode);
        return 0;
}

static int f2fs_ioc_getflags(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        unsigned int flags = fi->i_flags &
                        (FS_FL_USER_VISIBLE | FS_PROJINHERIT_FL);
        return put_user(flags, (int __user *)arg);
}

static int __f2fs_ioc_setflags(struct inode *inode, unsigned int flags)
{
        struct f2fs_inode_info *fi = F2FS_I(inode);
        unsigned int oldflags;

        /* Is it quota file? Do not allow user to mess with it */
        if (IS_NOQUOTA(inode))
                return -EPERM;

        flags = f2fs_mask_flags(inode->i_mode, flags);

        oldflags = fi->i_flags;

        if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL))
                if (!capable(CAP_LINUX_IMMUTABLE))
                        return -EPERM;

        flags = flags & (FS_FL_USER_MODIFIABLE | FS_PROJINHERIT_FL);
        flags |= oldflags & ~(FS_FL_USER_MODIFIABLE | FS_PROJINHERIT_FL);
        fi->i_flags = flags;

        if (fi->i_flags & FS_PROJINHERIT_FL)
                set_inode_flag(inode, FI_PROJ_INHERIT);
        else
                clear_inode_flag(inode, FI_PROJ_INHERIT);

        inode->i_ctime = current_time(inode);
        f2fs_set_inode_flags(inode);
        f2fs_mark_inode_dirty_sync(inode, false);
        return 0;
}

static int f2fs_ioc_setflags(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        unsigned int flags;
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        if (get_user(flags, (int __user *)arg))
                return -EFAULT;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        ret = __f2fs_ioc_setflags(inode, flags);

        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_getversion(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);

        return put_user(inode->i_generation, (int __user *)arg);
}

static int f2fs_ioc_start_atomic_write(struct file *filp)
{
        struct inode *inode = file_inode(filp);
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        if (!S_ISREG(inode->i_mode))
                return -EINVAL;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (f2fs_is_atomic_file(inode))
                goto out;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                goto out;

        set_inode_flag(inode, FI_ATOMIC_FILE);
        set_inode_flag(inode, FI_HOT_DATA);
        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);

        if (!get_dirty_pages(inode))
                goto inc_stat;

        f2fs_msg(F2FS_I_SB(inode)->sb, KERN_WARNING,
                "Unexpected flush for atomic writes: ino=%lu, npages=%u",
                                        inode->i_ino, get_dirty_pages(inode));
        ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX);
        if (ret) {
                clear_inode_flag(inode, FI_ATOMIC_FILE);
                clear_inode_flag(inode, FI_HOT_DATA);
                goto out;
        }

inc_stat:
        F2FS_I(inode)->inmem_task = current;
        stat_inc_atomic_write(inode);
        stat_update_max_atomic_write(inode);
out:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_commit_atomic_write(struct file *filp)
{
        struct inode *inode = file_inode(filp);
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (f2fs_is_volatile_file(inode))
                goto err_out;

        if (f2fs_is_atomic_file(inode)) {
                ret = commit_inmem_pages(inode);
                if (ret)
                        goto err_out;

                ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true);
                if (!ret) {
                        clear_inode_flag(inode, FI_ATOMIC_FILE);
                        clear_inode_flag(inode, FI_HOT_DATA);
                        stat_dec_atomic_write(inode);
                }
        } else {
                ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 1, false);
        }
err_out:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_start_volatile_write(struct file *filp)
{
        struct inode *inode = file_inode(filp);
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        if (!S_ISREG(inode->i_mode))
                return -EINVAL;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (f2fs_is_volatile_file(inode))
                goto out;

        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                goto out;

        stat_inc_volatile_write(inode);
        stat_update_max_volatile_write(inode);

        set_inode_flag(inode, FI_VOLATILE_FILE);
        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
out:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_release_volatile_write(struct file *filp)
{
        struct inode *inode = file_inode(filp);
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (!f2fs_is_volatile_file(inode))
                goto out;

        if (!f2fs_is_first_block_written(inode)) {
                ret = truncate_partial_data_page(inode, 0, true);
                goto out;
        }

        ret = punch_hole(inode, 0, F2FS_BLKSIZE);
out:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_abort_volatile_write(struct file *filp)
{
        struct inode *inode = file_inode(filp);
        int ret;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (f2fs_is_atomic_file(inode))
                drop_inmem_pages(inode);
        if (f2fs_is_volatile_file(inode)) {
                clear_inode_flag(inode, FI_VOLATILE_FILE);
                stat_dec_volatile_write(inode);
                ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true);
        }

        inode_unlock(inode);

        mnt_drop_write_file(filp);
        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
        return ret;
}

static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct super_block *sb = sbi->sb;
        __u32 in;
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (get_user(in, (__u32 __user *)arg))
                return -EFAULT;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        switch (in) {
        case F2FS_GOING_DOWN_FULLSYNC:
                sb = freeze_bdev(sb->s_bdev);
                if (IS_ERR(sb)) {
                        ret = PTR_ERR(sb);
                        goto out;
                }
                if (sb) {
                        f2fs_stop_checkpoint(sbi, false);
                        thaw_bdev(sb->s_bdev, sb);
                }
                break;
        case F2FS_GOING_DOWN_METASYNC:
                /* do checkpoint only */
                ret = f2fs_sync_fs(sb, 1);
                if (ret)
                        goto out;
                f2fs_stop_checkpoint(sbi, false);
                break;
        case F2FS_GOING_DOWN_NOSYNC:
                f2fs_stop_checkpoint(sbi, false);
                break;
        case F2FS_GOING_DOWN_METAFLUSH:
                sync_meta_pages(sbi, META, LONG_MAX, FS_META_IO);
                f2fs_stop_checkpoint(sbi, false);
                break;
        default:
                ret = -EINVAL;
                goto out;
        }

        stop_gc_thread(sbi);
        stop_discard_thread(sbi);

        drop_discard_cmd(sbi);
        clear_opt(sbi, DISCARD);

        f2fs_update_time(sbi, REQ_TIME);
out:
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_fitrim(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct super_block *sb = inode->i_sb;
        struct request_queue *q = bdev_get_queue(sb->s_bdev);
        struct fstrim_range range;
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (!blk_queue_discard(q))
                return -EOPNOTSUPP;

        if (copy_from_user(&range, (struct fstrim_range __user *)arg,
                                sizeof(range)))
                return -EFAULT;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        range.minlen = max((unsigned int)range.minlen,
                                q->limits.discard_granularity);
        ret = f2fs_trim_fs(F2FS_SB(sb), &range);
        mnt_drop_write_file(filp);
        if (ret < 0)
                return ret;

        if (copy_to_user((struct fstrim_range __user *)arg, &range,
                                sizeof(range)))
                return -EFAULT;
        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
        return 0;
}

static bool uuid_is_nonzero(__u8 u[16])
{
        int i;

        for (i = 0; i < 16; i++)
                if (u[i])
                        return true;
        return false;
}

static int f2fs_ioc_set_encryption_policy(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);

        if (!f2fs_sb_has_crypto(inode->i_sb))
                return -EOPNOTSUPP;

        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);

        return fscrypt_ioctl_set_policy(filp, (const void __user *)arg);
}

static int f2fs_ioc_get_encryption_policy(struct file *filp, unsigned long arg)
{
        if (!f2fs_sb_has_crypto(file_inode(filp)->i_sb))
                return -EOPNOTSUPP;
        return fscrypt_ioctl_get_policy(filp, (void __user *)arg);
}

static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        int err;

        if (!f2fs_sb_has_crypto(inode->i_sb))
                return -EOPNOTSUPP;

        if (uuid_is_nonzero(sbi->raw_super->encrypt_pw_salt))
                goto got_it;

        err = mnt_want_write_file(filp);
        if (err)
                return err;

        /* update superblock with uuid */
        generate_random_uuid(sbi->raw_super->encrypt_pw_salt);

        err = f2fs_commit_super(sbi, false);
        if (err) {
                /* undo new data */
                memset(sbi->raw_super->encrypt_pw_salt, 0, 16);
                mnt_drop_write_file(filp);
                return err;
        }
        mnt_drop_write_file(filp);
got_it:
        if (copy_to_user((__u8 __user *)arg, sbi->raw_super->encrypt_pw_salt,
                                                                        16))
                return -EFAULT;
        return 0;
}

static int f2fs_ioc_gc(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        __u32 sync;
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (get_user(sync, (__u32 __user *)arg))

                return -EFAULT;

        if (f2fs_readonly(sbi->sb))
                return -EROFS;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        if (!sync) {
                if (!mutex_trylock(&sbi->gc_mutex)) {
                        ret = -EBUSY;
                        goto out;
                }
        } else {
                mutex_lock(&sbi->gc_mutex);
        }

        ret = f2fs_gc(sbi, sync, true, NULL_SEGNO);
out:
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_gc_range(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct f2fs_gc_range range;
        u64 end;
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (copy_from_user(&range, (struct f2fs_gc_range __user *)arg,
                                                        sizeof(range)))
                return -EFAULT;

        if (f2fs_readonly(sbi->sb))
                return -EROFS;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        end = range.start + range.len;
        if (range.start < MAIN_BLKADDR(sbi) || end >= MAX_BLKADDR(sbi))
                return -EINVAL;
do_more:
        if (!range.sync) {
                if (!mutex_trylock(&sbi->gc_mutex)) {
                        ret = -EBUSY;
                        goto out;
                }
        } else {
                mutex_lock(&sbi->gc_mutex);
        }

        ret = f2fs_gc(sbi, range.sync, true, GET_SEGNO(sbi, range.start));
        range.start += sbi->blocks_per_seg;
        if (range.start <= end)
                goto do_more;
out:
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_write_checkpoint(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (f2fs_readonly(sbi->sb))
                return -EROFS;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        ret = f2fs_sync_fs(sbi->sb, 1);

        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_defragment_range(struct f2fs_sb_info *sbi,
                                        struct file *filp,
                                        struct f2fs_defragment *range)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_map_blocks map = { .m_next_extent = NULL,
                                        .m_seg_type = NO_CHECK_TYPE };
        struct extent_info ei = {0,0,0};
        pgoff_t pg_start, pg_end, next_pgofs;
        unsigned int blk_per_seg = sbi->blocks_per_seg;
        unsigned int total = 0, sec_num;
        block_t blk_end = 0;
        bool fragmented = false;
        int err;

        /* if in-place-update policy is enabled, don't waste time here */
        if (should_update_inplace(inode, NULL))
                return -EINVAL;

        pg_start = range->start >> PAGE_SHIFT;
        pg_end = (range->start + range->len) >> PAGE_SHIFT;

        f2fs_balance_fs(sbi, true);

        inode_lock(inode);

        /* writeback all dirty pages in the range */
        err = filemap_write_and_wait_range(inode->i_mapping, range->start,
                                                range->start + range->len - 1);
        if (err)
                goto out;

        /*
         * lookup mapping info in extent cache, skip defragmenting if physical
         * block addresses are continuous.
         */
        if (f2fs_lookup_extent_cache(inode, pg_start, &ei)) {
                if (ei.fofs + ei.len >= pg_end)
                        goto out;
        }

        map.m_lblk = pg_start;
        map.m_next_pgofs = &next_pgofs;

        /*
         * lookup mapping info in dnode page cache, skip defragmenting if all
         * physical block addresses are continuous even if there are hole(s)
         * in logical blocks.
         */
        while (map.m_lblk < pg_end) {
                map.m_len = pg_end - map.m_lblk;
                err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT);
                if (err)
                        goto out;

                if (!(map.m_flags & F2FS_MAP_FLAGS)) {
                        map.m_lblk = next_pgofs;
                        continue;
                }

                if (blk_end && blk_end != map.m_pblk)
                        fragmented = true;

                /* record total count of block that we're going to move */
                total += map.m_len;

                blk_end = map.m_pblk + map.m_len;

                map.m_lblk += map.m_len;
        }

        if (!fragmented)
                goto out;

        sec_num = (total + BLKS_PER_SEC(sbi) - 1) / BLKS_PER_SEC(sbi);

        /*
         * make sure there are enough free section for LFS allocation, this can
         * avoid defragment running in SSR mode when free section are allocated
         * intensively
         */
        if (has_not_enough_free_secs(sbi, 0, sec_num)) {
                err = -EAGAIN;
                goto out;
        }

        map.m_lblk = pg_start;
        map.m_len = pg_end - pg_start;
        total = 0;

        while (map.m_lblk < pg_end) {
                pgoff_t idx;
                int cnt = 0;

do_map:
                map.m_len = pg_end - map.m_lblk;
                err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT);
                if (err)
                        goto clear_out;

                if (!(map.m_flags & F2FS_MAP_FLAGS)) {
                        map.m_lblk = next_pgofs;
                        continue;
                }

                set_inode_flag(inode, FI_DO_DEFRAG);

                idx = map.m_lblk;
                while (idx < map.m_lblk + map.m_len && cnt < blk_per_seg) {
                        struct page *page;

                        page = get_lock_data_page(inode, idx, true);
                        if (IS_ERR(page)) {
                                err = PTR_ERR(page);
                                goto clear_out;
                        }

                        set_page_dirty(page);
                        f2fs_put_page(page, 1);

                        idx++;
                        cnt++;
                        total++;
                }

                map.m_lblk = idx;

                if (idx < pg_end && cnt < blk_per_seg)
                        goto do_map;

                clear_inode_flag(inode, FI_DO_DEFRAG);

                err = filemap_fdatawrite(inode->i_mapping);
                if (err)
                        goto out;
        }
clear_out:
        clear_inode_flag(inode, FI_DO_DEFRAG);
out:
        inode_unlock(inode);
        if (!err)
                range->len = (u64)total << PAGE_SHIFT;
        return err;
}

static int f2fs_ioc_defragment(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct f2fs_defragment range;
        int err;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (!S_ISREG(inode->i_mode) || f2fs_is_atomic_file(inode))
                return -EINVAL;

        if (f2fs_readonly(sbi->sb))
                return -EROFS;

        if (copy_from_user(&range, (struct f2fs_defragment __user *)arg,
                                                        sizeof(range)))
                return -EFAULT;

        /* verify alignment of offset & size */
        if (range.start & (F2FS_BLKSIZE - 1) || range.len & (F2FS_BLKSIZE - 1))
                return -EINVAL;

        if (unlikely((range.start + range.len) >> PAGE_SHIFT >
                                        sbi->max_file_blocks))
                return -EINVAL;

        err = mnt_want_write_file(filp);
        if (err)
                return err;

        err = f2fs_defragment_range(sbi, filp, &range);
        mnt_drop_write_file(filp);

        f2fs_update_time(sbi, REQ_TIME);
        if (err < 0)
                return err;

        if (copy_to_user((struct f2fs_defragment __user *)arg, &range,
                                                        sizeof(range)))
                return -EFAULT;

        return 0;
}

static int f2fs_move_file_range(struct file *file_in, loff_t pos_in,
                        struct file *file_out, loff_t pos_out, size_t len)
{
        struct inode *src = file_inode(file_in);
        struct inode *dst = file_inode(file_out);
        struct f2fs_sb_info *sbi = F2FS_I_SB(src);
        size_t olen = len, dst_max_i_size = 0;
        size_t dst_osize;
        int ret;

        if (file_in->f_path.mnt != file_out->f_path.mnt ||
                                src->i_sb != dst->i_sb)
                return -EXDEV;

        if (unlikely(f2fs_readonly(src->i_sb)))
                return -EROFS;

        if (!S_ISREG(src->i_mode) || !S_ISREG(dst->i_mode))
                return -EINVAL;

        if (f2fs_encrypted_inode(src) || f2fs_encrypted_inode(dst))
                return -EOPNOTSUPP;

        if (src == dst) {
                if (pos_in == pos_out)
                        return 0;
                if (pos_out > pos_in && pos_out < pos_in + len)
                        return -EINVAL;
        }

        inode_lock(src);
        down_write(&F2FS_I(src)->dio_rwsem[WRITE]);
        if (src != dst) {
                ret = -EBUSY;
                if (!inode_trylock(dst))
                        goto out;
                if (!down_write_trylock(&F2FS_I(dst)->dio_rwsem[WRITE])) {
                        inode_unlock(dst);
                        goto out;
                }
        }

        ret = -EINVAL;
        if (pos_in + len > src->i_size || pos_in + len < pos_in)
                goto out_unlock;
        if (len == 0)
                olen = len = src->i_size - pos_in;
        if (pos_in + len == src->i_size)
                len = ALIGN(src->i_size, F2FS_BLKSIZE) - pos_in;
        if (len == 0) {
                ret = 0;
                goto out_unlock;
        }

        dst_osize = dst->i_size;
        if (pos_out + olen > dst->i_size)
                dst_max_i_size = pos_out + olen;

        /* verify the end result is block aligned */
        if (!IS_ALIGNED(pos_in, F2FS_BLKSIZE) ||
                        !IS_ALIGNED(pos_in + len, F2FS_BLKSIZE) ||
                        !IS_ALIGNED(pos_out, F2FS_BLKSIZE))
                goto out_unlock;

        ret = f2fs_convert_inline_inode(src);
        if (ret)
                goto out_unlock;

        ret = f2fs_convert_inline_inode(dst);
        if (ret)
                goto out_unlock;

        /* write out all dirty pages from offset */
        ret = filemap_write_and_wait_range(src->i_mapping,
                                        pos_in, pos_in + len);
        if (ret)
                goto out_unlock;

        ret = filemap_write_and_wait_range(dst->i_mapping,
                                        pos_out, pos_out + len);
        if (ret)
                goto out_unlock;

        f2fs_balance_fs(sbi, true);
        f2fs_lock_op(sbi);
        ret = __exchange_data_block(src, dst, pos_in >> F2FS_BLKSIZE_BITS,
                                pos_out >> F2FS_BLKSIZE_BITS,
                                len >> F2FS_BLKSIZE_BITS, false);

        if (!ret) {
                if (dst_max_i_size)
                        f2fs_i_size_write(dst, dst_max_i_size);
                else if (dst_osize != dst->i_size)
                        f2fs_i_size_write(dst, dst_osize);
        }
        f2fs_unlock_op(sbi);
out_unlock:
        if (src != dst) {
                up_write(&F2FS_I(dst)->dio_rwsem[WRITE]);
                inode_unlock(dst);
        }
out:
        up_write(&F2FS_I(src)->dio_rwsem[WRITE]);
        inode_unlock(src);
        return ret;
}

static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
{
        struct f2fs_move_range range;
        struct fd dst;
        int err;

        if (!(filp->f_mode & FMODE_READ) ||
                        !(filp->f_mode & FMODE_WRITE))
                return -EBADF;

        if (copy_from_user(&range, (struct f2fs_move_range __user *)arg,
                                                        sizeof(range)))
                return -EFAULT;

        dst = fdget(range.dst_fd);
        if (!dst.file)
                return -EBADF;

        if (!(dst.file->f_mode & FMODE_WRITE)) {
                err = -EBADF;
                goto err_out;
        }

        err = mnt_want_write_file(filp);
        if (err)
                goto err_out;

        err = f2fs_move_file_range(filp, range.pos_in, dst.file,
                                        range.pos_out, range.len);

        mnt_drop_write_file(filp);
        if (err)
                goto err_out;

        if (copy_to_user((struct f2fs_move_range __user *)arg,
                                                &range, sizeof(range)))
                err = -EFAULT;
err_out:
        fdput(dst);
        return err;
}

static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct sit_info *sm = SIT_I(sbi);
        unsigned int start_segno = 0, end_segno = 0;
        unsigned int dev_start_segno = 0, dev_end_segno = 0;
        struct f2fs_flush_device range;
        int ret;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (f2fs_readonly(sbi->sb))
                return -EROFS;

        if (copy_from_user(&range, (struct f2fs_flush_device __user *)arg,
                                                        sizeof(range)))
                return -EFAULT;

        if (sbi->s_ndevs <= 1 || sbi->s_ndevs - 1 <= range.dev_num ||
                        sbi->segs_per_sec != 1) {
                f2fs_msg(sbi->sb, KERN_WARNING,
                        "Can't flush %u in %d for segs_per_sec %u != 1\n",
                                range.dev_num, sbi->s_ndevs,
                                sbi->segs_per_sec);
                return -EINVAL;
        }

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        if (range.dev_num != 0)
                dev_start_segno = GET_SEGNO(sbi, FDEV(range.dev_num).start_blk);
        dev_end_segno = GET_SEGNO(sbi, FDEV(range.dev_num).end_blk);

        start_segno = sm->last_victim[FLUSH_DEVICE];
        if (start_segno < dev_start_segno || start_segno >= dev_end_segno)
                start_segno = dev_start_segno;
        end_segno = min(start_segno + range.segments, dev_end_segno);

        while (start_segno < end_segno) {
                if (!mutex_trylock(&sbi->gc_mutex)) {
                        ret = -EBUSY;
                        goto out;
                }
                sm->last_victim[GC_CB] = end_segno + 1;
                sm->last_victim[GC_GREEDY] = end_segno + 1;
                sm->last_victim[ALLOC_NEXT] = end_segno + 1;
                ret = f2fs_gc(sbi, true, true, start_segno);
                if (ret == -EAGAIN)
                        ret = 0;
                else if (ret < 0)
                        break;
                start_segno++;
        }
out:
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_get_features(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature);

        /* Must validate to set it with SQLite behavior in Android. */
        sb_feature |= F2FS_FEATURE_ATOMIC_WRITE;

        return put_user(sb_feature, (u32 __user *)arg);
}

#ifdef CONFIG_QUOTA
static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct super_block *sb = sbi->sb;
        struct dquot *transfer_to[MAXQUOTAS] = {};
        struct page *ipage;
        kprojid_t kprojid;
        int err;

        if (!f2fs_sb_has_project_quota(sb)) {
                if (projid != F2FS_DEF_PROJID)
                        return -EOPNOTSUPP;
                else
                        return 0;
        }

        if (!f2fs_has_extra_attr(inode))
                return -EOPNOTSUPP;

        kprojid = make_kprojid(&init_user_ns, (projid_t)projid);

        if (projid_eq(kprojid, F2FS_I(inode)->i_projid))
                return 0;

        err = mnt_want_write_file(filp);
        if (err)
                return err;

        err = -EPERM;
        inode_lock(inode);

        /* Is it quota file? Do not allow user to mess with it */
        if (IS_NOQUOTA(inode))
                goto out_unlock;

        ipage = get_node_page(sbi, inode->i_ino);
        if (IS_ERR(ipage)) {
                err = PTR_ERR(ipage);
                goto out_unlock;
        }

        if (!F2FS_FITS_IN_INODE(F2FS_INODE(ipage), fi->i_extra_isize,
                                                                i_projid)) {
                err = -EOVERFLOW;
                f2fs_put_page(ipage, 1);
                goto out_unlock;
        }
        f2fs_put_page(ipage, 1);

        dquot_initialize(inode);

        transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
        if (!IS_ERR(transfer_to[PRJQUOTA])) {
                err = __dquot_transfer(inode, transfer_to);
                dqput(transfer_to[PRJQUOTA]);
                if (err)
                        goto out_dirty;
        }

        F2FS_I(inode)->i_projid = kprojid;
        inode->i_ctime = current_time(inode);
out_dirty:
        f2fs_mark_inode_dirty_sync(inode, true);
out_unlock:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return err;
}
#else
static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
{
        if (projid != F2FS_DEF_PROJID)
                return -EOPNOTSUPP;
        return 0;
}
#endif

/* Transfer internal flags to xflags */
static inline __u32 f2fs_iflags_to_xflags(unsigned long iflags)
{
        __u32 xflags = 0;

        if (iflags & FS_SYNC_FL)
                xflags |= FS_XFLAG_SYNC;
        if (iflags & FS_IMMUTABLE_FL)
                xflags |= FS_XFLAG_IMMUTABLE;
        if (iflags & FS_APPEND_FL)
                xflags |= FS_XFLAG_APPEND;
        if (iflags & FS_NODUMP_FL)
                xflags |= FS_XFLAG_NODUMP;
        if (iflags & FS_NOATIME_FL)
                xflags |= FS_XFLAG_NOATIME;
        if (iflags & FS_PROJINHERIT_FL)
                xflags |= FS_XFLAG_PROJINHERIT;
        return xflags;
}

#define F2FS_SUPPORTED_FS_XFLAGS (FS_XFLAG_SYNC | FS_XFLAG_IMMUTABLE | \
                                  FS_XFLAG_APPEND | FS_XFLAG_NODUMP | \
                                  FS_XFLAG_NOATIME | FS_XFLAG_PROJINHERIT)

/* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
#define F2FS_FL_XFLAG_VISIBLE           (FS_SYNC_FL | \
                                         FS_IMMUTABLE_FL | \
                                         FS_APPEND_FL | \
                                         FS_NODUMP_FL | \
                                         FS_NOATIME_FL | \
                                         FS_PROJINHERIT_FL)

/* Transfer xflags flags to internal */
static inline unsigned long f2fs_xflags_to_iflags(__u32 xflags)
{
        unsigned long iflags = 0;

        if (xflags & FS_XFLAG_SYNC)
                iflags |= FS_SYNC_FL;
        if (xflags & FS_XFLAG_IMMUTABLE)
                iflags |= FS_IMMUTABLE_FL;
        if (xflags & FS_XFLAG_APPEND)
                iflags |= FS_APPEND_FL;
        if (xflags & FS_XFLAG_NODUMP)
                iflags |= FS_NODUMP_FL;
        if (xflags & FS_XFLAG_NOATIME)
                iflags |= FS_NOATIME_FL;
        if (xflags & FS_XFLAG_PROJINHERIT)
                iflags |= FS_PROJINHERIT_FL;

        return iflags;
}

static int f2fs_ioc_fsgetxattr(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct fsxattr fa;

        memset(&fa, 0, sizeof(struct fsxattr));
        fa.fsx_xflags = f2fs_iflags_to_xflags(fi->i_flags &
                                (FS_FL_USER_VISIBLE | FS_PROJINHERIT_FL));

        if (f2fs_sb_has_project_quota(inode->i_sb))
                fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,
                                                        fi->i_projid);

        if (copy_to_user((struct fsxattr __user *)arg, &fa, sizeof(fa)))
                return -EFAULT;
        return 0;
}

static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct fsxattr fa;
        unsigned int flags;
        int err;

        if (copy_from_user(&fa, (struct fsxattr __user *)arg, sizeof(fa)))
                return -EFAULT;

        /* Make sure caller has proper permission */
        if (!inode_owner_or_capable(inode))
                return -EACCES;

        if (fa.fsx_xflags & ~F2FS_SUPPORTED_FS_XFLAGS)
                return -EOPNOTSUPP;

        flags = f2fs_xflags_to_iflags(fa.fsx_xflags);
        if (f2fs_mask_flags(inode->i_mode, flags) != flags)
                return -EOPNOTSUPP;

        err = mnt_want_write_file(filp);
        if (err)
                return err;

        inode_lock(inode);
        flags = (fi->i_flags & ~F2FS_FL_XFLAG_VISIBLE) |
                                (flags & F2FS_FL_XFLAG_VISIBLE);
        err = __f2fs_ioc_setflags(inode, flags);
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        if (err)
                return err;

        err = f2fs_ioc_setproject(filp, fa.fsx_projid);
        if (err)
                return err;

        return 0;
}

int f2fs_pin_file_control(struct inode *inode, bool inc)
{
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

        /* Use i_gc_failures for normal file as a risk signal. */
        if (inc)
                f2fs_i_gc_failures_write(inode, fi->i_gc_failures + 1);

        if (fi->i_gc_failures > sbi->gc_pin_file_threshold) {
                f2fs_msg(sbi->sb, KERN_WARNING,
                        "%s: Enable GC = ino %lx after %x GC trials\n",
                        __func__, inode->i_ino, fi->i_gc_failures);
                clear_inode_flag(inode, FI_PIN_FILE);
                return -EAGAIN;
        }
        return 0;
}

static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        __u32 pin;
        int ret = 0;

        if (!inode_owner_or_capable(inode))
                return -EACCES;

        if (get_user(pin, (__u32 __user *)arg))
                return -EFAULT;

        if (!S_ISREG(inode->i_mode))
                return -EINVAL;

        if (f2fs_readonly(F2FS_I_SB(inode)->sb))
                return -EROFS;

        ret = mnt_want_write_file(filp);
        if (ret)
                return ret;

        inode_lock(inode);

        if (should_update_outplace(inode, NULL)) {
                ret = -EINVAL;
                goto out;
        }

        if (!pin) {
                clear_inode_flag(inode, FI_PIN_FILE);
                F2FS_I(inode)->i_gc_failures = 1;
                goto done;
        }

        if (f2fs_pin_file_control(inode, false)) {
                ret = -EAGAIN;
                goto out;
        }
        ret = f2fs_convert_inline_inode(inode);
        if (ret)
                goto out;

        set_inode_flag(inode, FI_PIN_FILE);
        ret = F2FS_I(inode)->i_gc_failures;
done:
        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
out:
        inode_unlock(inode);
        mnt_drop_write_file(filp);
        return ret;
}

static int f2fs_ioc_get_pin_file(struct file *filp, unsigned long arg)
{
        struct inode *inode = file_inode(filp);
        __u32 pin = 0;

        if (is_inode_flag_set(inode, FI_PIN_FILE))
                pin = F2FS_I(inode)->i_gc_failures;
        return put_user(pin, (u32 __user *)arg);
}

int f2fs_precache_extents(struct inode *inode)
{
        struct f2fs_inode_info *fi = F2FS_I(inode);
        struct f2fs_map_blocks map;
        pgoff_t m_next_extent;
        loff_t end;
        int err;

        if (is_inode_flag_set(inode, FI_NO_EXTENT))
                return -EOPNOTSUPP;

        map.m_lblk = 0;
        map.m_next_pgofs = NULL;
        map.m_next_extent = &m_next_extent;
        map.m_seg_type = NO_CHECK_TYPE;
        end = F2FS_I_SB(inode)->max_file_blocks;

        while (map.m_lblk < end) {
                map.m_len = end - map.m_lblk;

                down_write(&fi->dio_rwsem[WRITE]);
                err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_PRECACHE);
                up_write(&fi->dio_rwsem[WRITE]);
                if (err)
                        return err;

                map.m_lblk = m_next_extent;
        }

        return err;
}

static int f2fs_ioc_precache_extents(struct file *filp, unsigned long arg)
{
        return f2fs_precache_extents(file_inode(filp));
}

long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
        if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp)))))
                return -EIO;

        switch (cmd) {
        case F2FS_IOC_GETFLAGS:
                return f2fs_ioc_getflags(filp, arg);
        case F2FS_IOC_SETFLAGS:
                return f2fs_ioc_setflags(filp, arg);
        case F2FS_IOC_GETVERSION:
                return f2fs_ioc_getversion(filp, arg);
        case F2FS_IOC_START_ATOMIC_WRITE:
                return f2fs_ioc_start_atomic_write(filp);
        case F2FS_IOC_COMMIT_ATOMIC_WRITE:
                return f2fs_ioc_commit_atomic_write(filp);
        case F2FS_IOC_START_VOLATILE_WRITE:
                return f2fs_ioc_start_volatile_write(filp);
        case F2FS_IOC_RELEASE_VOLATILE_WRITE:
                return f2fs_ioc_release_volatile_write(filp);
        case F2FS_IOC_ABORT_VOLATILE_WRITE:
                return f2fs_ioc_abort_volatile_write(filp);
        case F2FS_IOC_SHUTDOWN:
                return f2fs_ioc_shutdown(filp, arg);
        case FITRIM:
                return f2fs_ioc_fitrim(filp, arg);
        case F2FS_IOC_SET_ENCRYPTION_POLICY:
                return f2fs_ioc_set_encryption_policy(filp, arg);
        case F2FS_IOC_GET_ENCRYPTION_POLICY:
                return f2fs_ioc_get_encryption_policy(filp, arg);
        case F2FS_IOC_GET_ENCRYPTION_PWSALT:
                return f2fs_ioc_get_encryption_pwsalt(filp, arg);
        case F2FS_IOC_GARBAGE_COLLECT:
                return f2fs_ioc_gc(filp, arg);
        case F2FS_IOC_GARBAGE_COLLECT_RANGE:
                return f2fs_ioc_gc_range(filp, arg);
        case F2FS_IOC_WRITE_CHECKPOINT:
                return f2fs_ioc_write_checkpoint(filp, arg);
        case F2FS_IOC_DEFRAGMENT:
                return f2fs_ioc_defragment(filp, arg);
        case F2FS_IOC_MOVE_RANGE:
                return f2fs_ioc_move_range(filp, arg);
        case F2FS_IOC_FLUSH_DEVICE:
                return f2fs_ioc_flush_device(filp, arg);
        case F2FS_IOC_GET_FEATURES:
                return f2fs_ioc_get_features(filp, arg);
        case F2FS_IOC_FSGETXATTR:
                return f2fs_ioc_fsgetxattr(filp, arg);
        case F2FS_IOC_FSSETXATTR:
                return f2fs_ioc_fssetxattr(filp, arg);
        case F2FS_IOC_GET_PIN_FILE:
                return f2fs_ioc_get_pin_file(filp, arg);
        case F2FS_IOC_SET_PIN_FILE:
                return f2fs_ioc_set_pin_file(filp, arg);
        case F2FS_IOC_PRECACHE_EXTENTS:
                return f2fs_ioc_precache_extents(filp, arg);
        default:
                return -ENOTTY;
        }
}

static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
        struct file *file = iocb->ki_filp;
        struct inode *inode = file_inode(file);
        struct blk_plug plug;
        ssize_t ret;

        if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
                return -EIO;

        inode_lock(inode);
        ret = generic_write_checks(iocb, from);
        if (ret > 0) {
                int err;

                if (iov_iter_fault_in_readable(from, iov_iter_count(from)))
                        set_inode_flag(inode, FI_NO_PREALLOC);

                err = f2fs_preallocate_blocks(iocb, from);
                if (err) {
                        clear_inode_flag(inode, FI_NO_PREALLOC);
                        inode_unlock(inode);
                        return err;
                }
                blk_start_plug(&plug);
                ret = __generic_file_write_iter(iocb, from);
                blk_finish_plug(&plug);
                clear_inode_flag(inode, FI_NO_PREALLOC);

                if (ret > 0)
                        f2fs_update_iostat(F2FS_I_SB(inode), APP_WRITE_IO, ret);
        }
        inode_unlock(inode);

        if (ret > 0)
                ret = generic_write_sync(iocb, ret);
        return ret;
}

#ifdef CONFIG_COMPAT
long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
        switch (cmd) {
        case F2FS_IOC32_GETFLAGS:
                cmd = F2FS_IOC_GETFLAGS;
                break;
        case F2FS_IOC32_SETFLAGS:
                cmd = F2FS_IOC_SETFLAGS;
                break;
        case F2FS_IOC32_GETVERSION:
                cmd = F2FS_IOC_GETVERSION;
                break;
        case F2FS_IOC_START_ATOMIC_WRITE:
        case F2FS_IOC_COMMIT_ATOMIC_WRITE:
        case F2FS_IOC_START_VOLATILE_WRITE:
        case F2FS_IOC_RELEASE_VOLATILE_WRITE:
        case F2FS_IOC_ABORT_VOLATILE_WRITE:
        case F2FS_IOC_SHUTDOWN:
        case F2FS_IOC_SET_ENCRYPTION_POLICY:
        case F2FS_IOC_GET_ENCRYPTION_PWSALT:
        case F2FS_IOC_GET_ENCRYPTION_POLICY:
        case F2FS_IOC_GARBAGE_COLLECT:
        case F2FS_IOC_GARBAGE_COLLECT_RANGE:
        case F2FS_IOC_WRITE_CHECKPOINT:
        case F2FS_IOC_DEFRAGMENT:
        case F2FS_IOC_MOVE_RANGE:
        case F2FS_IOC_FLUSH_DEVICE:
        case F2FS_IOC_GET_FEATURES:
        case F2FS_IOC_FSGETXATTR:
        case F2FS_IOC_FSSETXATTR:
        case F2FS_IOC_GET_PIN_FILE:
        case F2FS_IOC_SET_PIN_FILE:
        case F2FS_IOC_PRECACHE_EXTENTS:
                break;
        default:
                return -ENOIOCTLCMD;
        }
        return f2fs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif

const struct file_operations f2fs_file_operations = {
        .llseek         = f2fs_llseek,
        .read_iter      = generic_file_read_iter,
        .write_iter     = f2fs_file_write_iter,
        .open           = f2fs_file_open,
        .release        = f2fs_release_file,
        .mmap           = f2fs_file_mmap,
        .flush          = f2fs_file_flush,
        .fsync          = f2fs_sync_file,
        .fallocate      = f2fs_fallocate,
        .unlocked_ioctl = f2fs_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = f2fs_compat_ioctl,
#endif
        .splice_read    = generic_file_splice_read,
        .splice_write   = iter_file_splice_write,
};