f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE

Added two ioctl to decompress/compress explicitly the compression
enabled file in "compress_mode=user" mount option.

Using these two ioctls, the users can make a control of compression
and decompression of their files.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 8241b8b..16ea10f 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4026,6 +4026,185 @@ out:
        return ret;
 }
 
+static int redirty_blocks(struct inode *inode, pgoff_t page_idx, int len)
+{
+       DEFINE_READAHEAD(ractl, NULL, inode->i_mapping, page_idx);
+       struct address_space *mapping = inode->i_mapping;
+       struct page *page;
+       pgoff_t redirty_idx = page_idx;
+       int i, page_len = 0, ret = 0;
+
+       page_cache_ra_unbounded(&ractl, len, 0);
+
+       for (i = 0; i < len; i++, page_idx++) {
+               page = read_cache_page(mapping, page_idx, NULL, NULL);
+               if (IS_ERR(page)) {
+                       ret = PTR_ERR(page);
+                       break;
+               }
+               page_len++;
+       }
+
+       for (i = 0; i < page_len; i++, redirty_idx++) {
+               page = find_lock_page(mapping, redirty_idx);
+               if (!page)
+                       ret = -ENOENT;
+               set_page_dirty(page);
+               f2fs_put_page(page, 1);
+               f2fs_put_page(page, 0);
+       }
+
+       return ret;
+}
+
+static int f2fs_ioc_decompress_file(struct file *filp, unsigned long arg)
+{
+       struct inode *inode = file_inode(filp);
+       struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+       struct f2fs_inode_info *fi = F2FS_I(inode);
+       pgoff_t page_idx = 0, last_idx;
+       unsigned int blk_per_seg = sbi->blocks_per_seg;
+       int cluster_size = F2FS_I(inode)->i_cluster_size;
+       int count, ret;
+
+       if (!f2fs_sb_has_compression(sbi) ||
+                       F2FS_OPTION(sbi).compress_mode != COMPR_MODE_USER)
+               return -EOPNOTSUPP;
+
+       if (!(filp->f_mode & FMODE_WRITE))
+               return -EBADF;
+
+       if (!f2fs_compressed_file(inode))
+               return -EINVAL;
+
+       f2fs_balance_fs(F2FS_I_SB(inode), true);
+
+       file_start_write(filp);
+       inode_lock(inode);
+
+       if (!f2fs_is_compress_backend_ready(inode)) {
+               ret = -EOPNOTSUPP;
+               goto out;
+       }
+
+       if (f2fs_is_mmap_file(inode)) {
+               ret = -EBUSY;
+               goto out;
+       }
+
+       ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX);
+       if (ret)
+               goto out;
+
+       if (!atomic_read(&fi->i_compr_blocks))
+               goto out;
+
+       last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+
+       count = last_idx - page_idx;
+       while (count) {
+               int len = min(cluster_size, count);
+
+               ret = redirty_blocks(inode, page_idx, len);
+               if (ret < 0)
+                       break;
+
+               if (get_dirty_pages(inode) >= blk_per_seg)
+                       filemap_fdatawrite(inode->i_mapping);
+
+               count -= len;
+               page_idx += len;
+       }
+
+       if (!ret)
+               ret = filemap_write_and_wait_range(inode->i_mapping, 0,
+                                                       LLONG_MAX);
+
+       if (ret)
+               f2fs_warn(sbi, "%s: The file might be partially decompressed "
+                               "(errno=%d). Please delete the file.\n",
+                               __func__, ret);
+out:
+       inode_unlock(inode);
+       file_end_write(filp);
+
+       return ret;
+}
+
+static int f2fs_ioc_compress_file(struct file *filp, unsigned long arg)
+{
+       struct inode *inode = file_inode(filp);
+       struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+       pgoff_t page_idx = 0, last_idx;
+       unsigned int blk_per_seg = sbi->blocks_per_seg;
+       int cluster_size = F2FS_I(inode)->i_cluster_size;
+       int count, ret;
+
+       if (!f2fs_sb_has_compression(sbi) ||
+                       F2FS_OPTION(sbi).compress_mode != COMPR_MODE_USER)
+               return -EOPNOTSUPP;
+
+       if (!(filp->f_mode & FMODE_WRITE))
+               return -EBADF;
+
+       if (!f2fs_compressed_file(inode))
+               return -EINVAL;
+
+       f2fs_balance_fs(F2FS_I_SB(inode), true);
+
+       file_start_write(filp);
+       inode_lock(inode);
+
+       if (!f2fs_is_compress_backend_ready(inode)) {
+               ret = -EOPNOTSUPP;
+               goto out;
+       }
+
+       if (f2fs_is_mmap_file(inode)) {
+               ret = -EBUSY;
+               goto out;
+       }
+
+       ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX);
+       if (ret)
+               goto out;
+
+       set_inode_flag(inode, FI_ENABLE_COMPRESS);
+
+       last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+
+       count = last_idx - page_idx;
+       while (count) {
+               int len = min(cluster_size, count);
+
+               ret = redirty_blocks(inode, page_idx, len);
+               if (ret < 0)
+                       break;
+
+               if (get_dirty_pages(inode) >= blk_per_seg)
+                       filemap_fdatawrite(inode->i_mapping);
+
+               count -= len;
+               page_idx += len;
+       }
+
+       if (!ret)
+               ret = filemap_write_and_wait_range(inode->i_mapping, 0,
+                                                       LLONG_MAX);
+
+       clear_inode_flag(inode, FI_ENABLE_COMPRESS);
+
+       if (ret)
+               f2fs_warn(sbi, "%s: The file might be partially compressed "
+                               "(errno=%d). Please delete the file.\n",
+                               __func__, ret);
+out:
+       inode_unlock(inode);
+       file_end_write(filp);
+
+       return ret;
+}
+
 static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
        switch (cmd) {
@@ -4113,6 +4292,10 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                return f2fs_ioc_get_compress_option(filp, arg);
        case F2FS_IOC_SET_COMPRESS_OPTION:
                return f2fs_ioc_set_compress_option(filp, arg);
+       case F2FS_IOC_DECOMPRESS_FILE:
+               return f2fs_ioc_decompress_file(filp, arg);
+       case F2FS_IOC_COMPRESS_FILE:
+               return f2fs_ioc_compress_file(filp, arg);
        default:
                return -ENOTTY;
        }
@@ -4352,6 +4535,8 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
        case F2FS_IOC_SEC_TRIM_FILE:
        case F2FS_IOC_GET_COMPRESS_OPTION:
        case F2FS_IOC_SET_COMPRESS_OPTION:
+       case F2FS_IOC_DECOMPRESS_FILE:
+       case F2FS_IOC_COMPRESS_FILE:
                break;
        default:
                return -ENOIOCTLCMD;

diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h
index f00199a..352a822 100644 (file)
--- a/include/uapi/linux/f2fs.h
+++ b/include/uapi/linux/f2fs.h
@@ -40,6 +40,8 @@
                                                struct f2fs_comp_option)
 #define F2FS_IOC_SET_COMPRESS_OPTION   _IOW(F2FS_IOCTL_MAGIC, 22,      \
                                                struct f2fs_comp_option)
+#define F2FS_IOC_DECOMPRESS_FILE       _IO(F2FS_IOCTL_MAGIC, 23)
+#define F2FS_IOC_COMPRESS_FILE         _IO(F2FS_IOCTL_MAGIC, 24)
 
 /*
  * should be same as XFS_IOC_GOINGDOWN.