745 lines
18 KiB
C
745 lines
18 KiB
C
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/*
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* linux/fs/ext4/file.c
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*
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* Copyright (C) 1992, 1993, 1994, 1995
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* Remy Card (card@masi.ibp.fr)
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* Laboratoire MASI - Institut Blaise Pascal
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* Universite Pierre et Marie Curie (Paris VI)
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*
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* from
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*
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* linux/fs/minix/file.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* ext4 fs regular file handling primitives
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*
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* 64-bit file support on 64-bit platforms by Jakub Jelinek
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* (jj@sunsite.ms.mff.cuni.cz)
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*/
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#include <linux/time.h>
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#include <linux/fs.h>
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#include <linux/mount.h>
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#include <linux/path.h>
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#include <linux/dax.h>
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#include <linux/quotaops.h>
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#include <linux/pagevec.h>
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#include <linux/uio.h>
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#include "ext4.h"
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#include "ext4_jbd2.h"
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#include "xattr.h"
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#include "acl.h"
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#ifdef CONFIG_FS_DAX
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static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
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{
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struct inode *inode = file_inode(iocb->ki_filp);
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ssize_t ret;
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inode_lock_shared(inode);
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/*
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* Recheck under inode lock - at this point we are sure it cannot
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* change anymore
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*/
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if (!IS_DAX(inode)) {
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inode_unlock_shared(inode);
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/* Fallback to buffered IO in case we cannot support DAX */
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return generic_file_read_iter(iocb, to);
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}
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ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops);
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inode_unlock_shared(inode);
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file_accessed(iocb->ki_filp);
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return ret;
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}
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#endif
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static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
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{
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if (unlikely(ext4_forced_shutdown(EXT4_SB(file_inode(iocb->ki_filp)->i_sb))))
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return -EIO;
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if (!iov_iter_count(to))
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return 0; /* skip atime */
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#ifdef CONFIG_FS_DAX
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if (IS_DAX(file_inode(iocb->ki_filp)))
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return ext4_dax_read_iter(iocb, to);
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#endif
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return generic_file_read_iter(iocb, to);
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}
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/*
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* Called when an inode is released. Note that this is different
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* from ext4_file_open: open gets called at every open, but release
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* gets called only when /all/ the files are closed.
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*/
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static int ext4_release_file(struct inode *inode, struct file *filp)
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{
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if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) {
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ext4_alloc_da_blocks(inode);
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ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
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}
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/* if we are the last writer on the inode, drop the block reservation */
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if ((filp->f_mode & FMODE_WRITE) &&
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(atomic_read(&inode->i_writecount) == 1) &&
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!EXT4_I(inode)->i_reserved_data_blocks)
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{
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down_write(&EXT4_I(inode)->i_data_sem);
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ext4_discard_preallocations(inode);
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up_write(&EXT4_I(inode)->i_data_sem);
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}
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if (is_dx(inode) && filp->private_data)
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ext4_htree_free_dir_info(filp->private_data);
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return 0;
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}
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static void ext4_unwritten_wait(struct inode *inode)
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{
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wait_queue_head_t *wq = ext4_ioend_wq(inode);
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wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_unwritten) == 0));
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}
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/*
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* This tests whether the IO in question is block-aligned or not.
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* Ext4 utilizes unwritten extents when hole-filling during direct IO, and they
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* are converted to written only after the IO is complete. Until they are
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* mapped, these blocks appear as holes, so dio_zero_block() will assume that
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* it needs to zero out portions of the start and/or end block. If 2 AIO
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* threads are at work on the same unwritten block, they must be synchronized
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* or one thread will zero the other's data, causing corruption.
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*/
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static int
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ext4_unaligned_aio(struct inode *inode, struct iov_iter *from, loff_t pos)
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{
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struct super_block *sb = inode->i_sb;
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int blockmask = sb->s_blocksize - 1;
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if (pos >= i_size_read(inode))
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return 0;
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if ((pos | iov_iter_alignment(from)) & blockmask)
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return 1;
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return 0;
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}
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/* Is IO overwriting allocated and initialized blocks? */
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static bool ext4_overwrite_io(struct inode *inode, loff_t pos, loff_t len)
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{
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struct ext4_map_blocks map;
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unsigned int blkbits = inode->i_blkbits;
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int err, blklen;
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if (pos + len > i_size_read(inode))
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return false;
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map.m_lblk = pos >> blkbits;
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map.m_len = EXT4_MAX_BLOCKS(len, pos, blkbits);
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blklen = map.m_len;
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err = ext4_map_blocks(NULL, inode, &map, 0);
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/*
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* 'err==len' means that all of the blocks have been preallocated,
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* regardless of whether they have been initialized or not. To exclude
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* unwritten extents, we need to check m_flags.
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*/
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return err == blklen && (map.m_flags & EXT4_MAP_MAPPED);
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}
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static ssize_t ext4_write_checks(struct kiocb *iocb, struct iov_iter *from)
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{
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struct inode *inode = file_inode(iocb->ki_filp);
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ssize_t ret;
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ret = generic_write_checks(iocb, from);
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if (ret <= 0)
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return ret;
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/*
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* If we have encountered a bitmap-format file, the size limit
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* is smaller than s_maxbytes, which is for extent-mapped files.
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*/
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if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
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struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
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if (iocb->ki_pos >= sbi->s_bitmap_maxbytes)
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return -EFBIG;
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iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos);
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}
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return iov_iter_count(from);
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}
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#ifdef CONFIG_FS_DAX
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static ssize_t
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ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
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{
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struct inode *inode = file_inode(iocb->ki_filp);
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ssize_t ret;
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inode_lock(inode);
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ret = ext4_write_checks(iocb, from);
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if (ret <= 0)
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goto out;
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ret = file_remove_privs(iocb->ki_filp);
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if (ret)
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goto out;
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ret = file_update_time(iocb->ki_filp);
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if (ret)
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goto out;
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ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops);
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out:
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inode_unlock(inode);
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if (ret > 0)
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ret = generic_write_sync(iocb, ret);
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return ret;
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}
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#endif
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static ssize_t
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ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
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{
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struct inode *inode = file_inode(iocb->ki_filp);
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int o_direct = iocb->ki_flags & IOCB_DIRECT;
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int unaligned_aio = 0;
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int overwrite = 0;
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ssize_t ret;
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if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
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return -EIO;
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#ifdef CONFIG_FS_DAX
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if (IS_DAX(inode))
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return ext4_dax_write_iter(iocb, from);
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#endif
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inode_lock(inode);
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ret = ext4_write_checks(iocb, from);
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if (ret <= 0)
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goto out;
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/*
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* Unaligned direct AIO must be serialized among each other as zeroing
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* of partial blocks of two competing unaligned AIOs can result in data
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* corruption.
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*/
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if (o_direct && ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
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!is_sync_kiocb(iocb) &&
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ext4_unaligned_aio(inode, from, iocb->ki_pos)) {
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unaligned_aio = 1;
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ext4_unwritten_wait(inode);
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}
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iocb->private = &overwrite;
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/* Check whether we do a DIO overwrite or not */
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if (o_direct && ext4_should_dioread_nolock(inode) && !unaligned_aio &&
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ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from)))
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overwrite = 1;
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ret = __generic_file_write_iter(iocb, from);
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inode_unlock(inode);
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if (ret > 0)
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ret = generic_write_sync(iocb, ret);
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return ret;
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out:
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inode_unlock(inode);
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return ret;
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}
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#ifdef CONFIG_FS_DAX
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static int ext4_dax_huge_fault(struct vm_fault *vmf,
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enum page_entry_size pe_size)
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{
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int result;
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handle_t *handle = NULL;
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struct inode *inode = file_inode(vmf->vma->vm_file);
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struct super_block *sb = inode->i_sb;
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bool write = vmf->flags & FAULT_FLAG_WRITE;
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if (write) {
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sb_start_pagefault(sb);
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file_update_time(vmf->vma->vm_file);
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down_read(&EXT4_I(inode)->i_mmap_sem);
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handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE,
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EXT4_DATA_TRANS_BLOCKS(sb));
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} else {
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down_read(&EXT4_I(inode)->i_mmap_sem);
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}
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if (!IS_ERR(handle))
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result = dax_iomap_fault(vmf, pe_size, &ext4_iomap_ops);
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else
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result = VM_FAULT_SIGBUS;
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if (write) {
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if (!IS_ERR(handle))
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ext4_journal_stop(handle);
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up_read(&EXT4_I(inode)->i_mmap_sem);
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sb_end_pagefault(sb);
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} else {
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up_read(&EXT4_I(inode)->i_mmap_sem);
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}
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return result;
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}
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static int ext4_dax_fault(struct vm_fault *vmf)
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{
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return ext4_dax_huge_fault(vmf, PE_SIZE_PTE);
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}
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/*
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* Handle write fault for VM_MIXEDMAP mappings. Similarly to ext4_dax_fault()
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* handler we check for races agaist truncate. Note that since we cycle through
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* i_mmap_sem, we are sure that also any hole punching that began before we
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* were called is finished by now and so if it included part of the file we
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* are working on, our pte will get unmapped and the check for pte_same() in
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* wp_pfn_shared() fails. Thus fault gets retried and things work out as
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* desired.
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*/
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static int ext4_dax_pfn_mkwrite(struct vm_fault *vmf)
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{
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struct inode *inode = file_inode(vmf->vma->vm_file);
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struct super_block *sb = inode->i_sb;
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loff_t size;
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int ret;
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sb_start_pagefault(sb);
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file_update_time(vmf->vma->vm_file);
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down_read(&EXT4_I(inode)->i_mmap_sem);
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size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
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if (vmf->pgoff >= size)
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ret = VM_FAULT_SIGBUS;
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else
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ret = dax_pfn_mkwrite(vmf);
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up_read(&EXT4_I(inode)->i_mmap_sem);
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sb_end_pagefault(sb);
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return ret;
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}
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static const struct vm_operations_struct ext4_dax_vm_ops = {
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.fault = ext4_dax_fault,
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.huge_fault = ext4_dax_huge_fault,
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.page_mkwrite = ext4_dax_fault,
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.pfn_mkwrite = ext4_dax_pfn_mkwrite,
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};
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#else
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#define ext4_dax_vm_ops ext4_file_vm_ops
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#endif
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static const struct vm_operations_struct ext4_file_vm_ops = {
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.fault = ext4_filemap_fault,
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.map_pages = filemap_map_pages,
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.page_mkwrite = ext4_page_mkwrite,
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};
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static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct inode *inode = file->f_mapping->host;
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if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
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return -EIO;
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if (ext4_encrypted_inode(inode)) {
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int err = fscrypt_get_encryption_info(inode);
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if (err)
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return 0;
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if (!fscrypt_has_encryption_key(inode))
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return -ENOKEY;
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}
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file_accessed(file);
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if (IS_DAX(file_inode(file))) {
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vma->vm_ops = &ext4_dax_vm_ops;
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vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
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} else {
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vma->vm_ops = &ext4_file_vm_ops;
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}
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return 0;
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}
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static int ext4_file_open(struct inode * inode, struct file * filp)
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{
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struct super_block *sb = inode->i_sb;
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struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
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struct vfsmount *mnt = filp->f_path.mnt;
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struct dentry *dir;
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struct path path;
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char buf[64], *cp;
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int ret;
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if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
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return -EIO;
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if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) &&
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!(sb->s_flags & MS_RDONLY))) {
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sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
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/*
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* Sample where the filesystem has been mounted and
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* store it in the superblock for sysadmin convenience
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* when trying to sort through large numbers of block
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* devices or filesystem images.
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*/
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memset(buf, 0, sizeof(buf));
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path.mnt = mnt;
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path.dentry = mnt->mnt_root;
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cp = d_path(&path, buf, sizeof(buf));
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if (!IS_ERR(cp)) {
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handle_t *handle;
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int err;
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handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
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if (IS_ERR(handle))
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return PTR_ERR(handle);
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BUFFER_TRACE(sbi->s_sbh, "get_write_access");
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err = ext4_journal_get_write_access(handle, sbi->s_sbh);
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if (err) {
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ext4_journal_stop(handle);
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return err;
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}
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strlcpy(sbi->s_es->s_last_mounted, cp,
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sizeof(sbi->s_es->s_last_mounted));
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ext4_handle_dirty_super(handle, sb);
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ext4_journal_stop(handle);
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}
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}
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||
|
if (ext4_encrypted_inode(inode)) {
|
||
|
ret = fscrypt_get_encryption_info(inode);
|
||
|
if (ret)
|
||
|
return -EACCES;
|
||
|
if (!fscrypt_has_encryption_key(inode))
|
||
|
return -ENOKEY;
|
||
|
}
|
||
|
|
||
|
dir = dget_parent(file_dentry(filp));
|
||
|
if (ext4_encrypted_inode(d_inode(dir)) &&
|
||
|
!fscrypt_has_permitted_context(d_inode(dir), inode)) {
|
||
|
ext4_warning(inode->i_sb,
|
||
|
"Inconsistent encryption contexts: %lu/%lu",
|
||
|
(unsigned long) d_inode(dir)->i_ino,
|
||
|
(unsigned long) inode->i_ino);
|
||
|
dput(dir);
|
||
|
return -EPERM;
|
||
|
}
|
||
|
dput(dir);
|
||
|
/*
|
||
|
* Set up the jbd2_inode if we are opening the inode for
|
||
|
* writing and the journal is present
|
||
|
*/
|
||
|
if (filp->f_mode & FMODE_WRITE) {
|
||
|
ret = ext4_inode_attach_jinode(inode);
|
||
|
if (ret < 0)
|
||
|
return ret;
|
||
|
}
|
||
|
return dquot_file_open(inode, filp);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Here we use ext4_map_blocks() to get a block mapping for a extent-based
|
||
|
* file rather than ext4_ext_walk_space() because we can introduce
|
||
|
* SEEK_DATA/SEEK_HOLE for block-mapped and extent-mapped file at the same
|
||
|
* function. When extent status tree has been fully implemented, it will
|
||
|
* track all extent status for a file and we can directly use it to
|
||
|
* retrieve the offset for SEEK_DATA/SEEK_HOLE.
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* When we retrieve the offset for SEEK_DATA/SEEK_HOLE, we would need to
|
||
|
* lookup page cache to check whether or not there has some data between
|
||
|
* [startoff, endoff] because, if this range contains an unwritten extent,
|
||
|
* we determine this extent as a data or a hole according to whether the
|
||
|
* page cache has data or not.
|
||
|
*/
|
||
|
static int ext4_find_unwritten_pgoff(struct inode *inode,
|
||
|
int whence,
|
||
|
ext4_lblk_t end_blk,
|
||
|
loff_t *offset)
|
||
|
{
|
||
|
struct pagevec pvec;
|
||
|
unsigned int blkbits;
|
||
|
pgoff_t index;
|
||
|
pgoff_t end;
|
||
|
loff_t endoff;
|
||
|
loff_t startoff;
|
||
|
loff_t lastoff;
|
||
|
int found = 0;
|
||
|
|
||
|
blkbits = inode->i_sb->s_blocksize_bits;
|
||
|
startoff = *offset;
|
||
|
lastoff = startoff;
|
||
|
endoff = (loff_t)end_blk << blkbits;
|
||
|
|
||
|
index = startoff >> PAGE_SHIFT;
|
||
|
end = (endoff - 1) >> PAGE_SHIFT;
|
||
|
|
||
|
pagevec_init(&pvec, 0);
|
||
|
do {
|
||
|
int i, num;
|
||
|
unsigned long nr_pages;
|
||
|
|
||
|
num = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
|
||
|
nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
|
||
|
(pgoff_t)num);
|
||
|
if (nr_pages == 0)
|
||
|
break;
|
||
|
|
||
|
for (i = 0; i < nr_pages; i++) {
|
||
|
struct page *page = pvec.pages[i];
|
||
|
struct buffer_head *bh, *head;
|
||
|
|
||
|
/*
|
||
|
* If current offset is smaller than the page offset,
|
||
|
* there is a hole at this offset.
|
||
|
*/
|
||
|
if (whence == SEEK_HOLE && lastoff < endoff &&
|
||
|
lastoff < page_offset(pvec.pages[i])) {
|
||
|
found = 1;
|
||
|
*offset = lastoff;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
if (page->index > end)
|
||
|
goto out;
|
||
|
|
||
|
lock_page(page);
|
||
|
|
||
|
if (unlikely(page->mapping != inode->i_mapping)) {
|
||
|
unlock_page(page);
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
if (!page_has_buffers(page)) {
|
||
|
unlock_page(page);
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
if (page_has_buffers(page)) {
|
||
|
lastoff = page_offset(page);
|
||
|
bh = head = page_buffers(page);
|
||
|
do {
|
||
|
if (buffer_uptodate(bh) ||
|
||
|
buffer_unwritten(bh)) {
|
||
|
if (whence == SEEK_DATA)
|
||
|
found = 1;
|
||
|
} else {
|
||
|
if (whence == SEEK_HOLE)
|
||
|
found = 1;
|
||
|
}
|
||
|
if (found) {
|
||
|
*offset = max_t(loff_t,
|
||
|
startoff, lastoff);
|
||
|
unlock_page(page);
|
||
|
goto out;
|
||
|
}
|
||
|
lastoff += bh->b_size;
|
||
|
bh = bh->b_this_page;
|
||
|
} while (bh != head);
|
||
|
}
|
||
|
|
||
|
lastoff = page_offset(page) + PAGE_SIZE;
|
||
|
unlock_page(page);
|
||
|
}
|
||
|
|
||
|
/* The no. of pages is less than our desired, we are done. */
|
||
|
if (nr_pages < num)
|
||
|
break;
|
||
|
|
||
|
index = pvec.pages[i - 1]->index + 1;
|
||
|
pagevec_release(&pvec);
|
||
|
} while (index <= end);
|
||
|
|
||
|
if (whence == SEEK_HOLE && lastoff < endoff) {
|
||
|
found = 1;
|
||
|
*offset = lastoff;
|
||
|
}
|
||
|
out:
|
||
|
pagevec_release(&pvec);
|
||
|
return found;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ext4_seek_data() retrieves the offset for SEEK_DATA.
|
||
|
*/
|
||
|
static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
|
||
|
{
|
||
|
struct inode *inode = file->f_mapping->host;
|
||
|
struct extent_status es;
|
||
|
ext4_lblk_t start, last, end;
|
||
|
loff_t dataoff, isize;
|
||
|
int blkbits;
|
||
|
int ret;
|
||
|
|
||
|
inode_lock(inode);
|
||
|
|
||
|
isize = i_size_read(inode);
|
||
|
if (offset >= isize) {
|
||
|
inode_unlock(inode);
|
||
|
return -ENXIO;
|
||
|
}
|
||
|
|
||
|
blkbits = inode->i_sb->s_blocksize_bits;
|
||
|
start = offset >> blkbits;
|
||
|
last = start;
|
||
|
end = isize >> blkbits;
|
||
|
dataoff = offset;
|
||
|
|
||
|
do {
|
||
|
ret = ext4_get_next_extent(inode, last, end - last + 1, &es);
|
||
|
if (ret <= 0) {
|
||
|
/* No extent found -> no data */
|
||
|
if (ret == 0)
|
||
|
ret = -ENXIO;
|
||
|
inode_unlock(inode);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
last = es.es_lblk;
|
||
|
if (last != start)
|
||
|
dataoff = (loff_t)last << blkbits;
|
||
|
if (!ext4_es_is_unwritten(&es))
|
||
|
break;
|
||
|
|
||
|
/*
|
||
|
* If there is a unwritten extent at this offset,
|
||
|
* it will be as a data or a hole according to page
|
||
|
* cache that has data or not.
|
||
|
*/
|
||
|
if (ext4_find_unwritten_pgoff(inode, SEEK_DATA,
|
||
|
es.es_lblk + es.es_len, &dataoff))
|
||
|
break;
|
||
|
last += es.es_len;
|
||
|
dataoff = (loff_t)last << blkbits;
|
||
|
cond_resched();
|
||
|
} while (last <= end);
|
||
|
|
||
|
inode_unlock(inode);
|
||
|
|
||
|
if (dataoff > isize)
|
||
|
return -ENXIO;
|
||
|
|
||
|
return vfs_setpos(file, dataoff, maxsize);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ext4_seek_hole() retrieves the offset for SEEK_HOLE.
|
||
|
*/
|
||
|
static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
|
||
|
{
|
||
|
struct inode *inode = file->f_mapping->host;
|
||
|
struct extent_status es;
|
||
|
ext4_lblk_t start, last, end;
|
||
|
loff_t holeoff, isize;
|
||
|
int blkbits;
|
||
|
int ret;
|
||
|
|
||
|
inode_lock(inode);
|
||
|
|
||
|
isize = i_size_read(inode);
|
||
|
if (offset >= isize) {
|
||
|
inode_unlock(inode);
|
||
|
return -ENXIO;
|
||
|
}
|
||
|
|
||
|
blkbits = inode->i_sb->s_blocksize_bits;
|
||
|
start = offset >> blkbits;
|
||
|
last = start;
|
||
|
end = isize >> blkbits;
|
||
|
holeoff = offset;
|
||
|
|
||
|
do {
|
||
|
ret = ext4_get_next_extent(inode, last, end - last + 1, &es);
|
||
|
if (ret < 0) {
|
||
|
inode_unlock(inode);
|
||
|
return ret;
|
||
|
}
|
||
|
/* Found a hole? */
|
||
|
if (ret == 0 || es.es_lblk > last) {
|
||
|
if (last != start)
|
||
|
holeoff = (loff_t)last << blkbits;
|
||
|
break;
|
||
|
}
|
||
|
/*
|
||
|
* If there is a unwritten extent at this offset,
|
||
|
* it will be as a data or a hole according to page
|
||
|
* cache that has data or not.
|
||
|
*/
|
||
|
if (ext4_es_is_unwritten(&es) &&
|
||
|
ext4_find_unwritten_pgoff(inode, SEEK_HOLE,
|
||
|
last + es.es_len, &holeoff))
|
||
|
break;
|
||
|
|
||
|
last += es.es_len;
|
||
|
holeoff = (loff_t)last << blkbits;
|
||
|
cond_resched();
|
||
|
} while (last <= end);
|
||
|
|
||
|
inode_unlock(inode);
|
||
|
|
||
|
if (holeoff > isize)
|
||
|
holeoff = isize;
|
||
|
|
||
|
return vfs_setpos(file, holeoff, maxsize);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ext4_llseek() handles both block-mapped and extent-mapped maxbytes values
|
||
|
* by calling generic_file_llseek_size() with the appropriate maxbytes
|
||
|
* value for each.
|
||
|
*/
|
||
|
loff_t ext4_llseek(struct file *file, loff_t offset, int whence)
|
||
|
{
|
||
|
struct inode *inode = file->f_mapping->host;
|
||
|
loff_t maxbytes;
|
||
|
|
||
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
|
||
|
maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes;
|
||
|
else
|
||
|
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:
|
||
|
return ext4_seek_data(file, offset, maxbytes);
|
||
|
case SEEK_HOLE:
|
||
|
return ext4_seek_hole(file, offset, maxbytes);
|
||
|
}
|
||
|
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
const struct file_operations ext4_file_operations = {
|
||
|
.llseek = ext4_llseek,
|
||
|
.read_iter = ext4_file_read_iter,
|
||
|
.write_iter = ext4_file_write_iter,
|
||
|
.unlocked_ioctl = ext4_ioctl,
|
||
|
#ifdef CONFIG_COMPAT
|
||
|
.compat_ioctl = ext4_compat_ioctl,
|
||
|
#endif
|
||
|
.mmap = ext4_file_mmap,
|
||
|
.open = ext4_file_open,
|
||
|
.release = ext4_release_file,
|
||
|
.fsync = ext4_sync_file,
|
||
|
.get_unmapped_area = thp_get_unmapped_area,
|
||
|
.splice_read = generic_file_splice_read,
|
||
|
.splice_write = iter_file_splice_write,
|
||
|
.fallocate = ext4_fallocate,
|
||
|
};
|
||
|
|
||
|
const struct inode_operations ext4_file_inode_operations = {
|
||
|
.setattr = ext4_setattr,
|
||
|
.getattr = ext4_file_getattr,
|
||
|
.listxattr = ext4_listxattr,
|
||
|
.get_acl = ext4_get_acl,
|
||
|
.set_acl = ext4_set_acl,
|
||
|
.fiemap = ext4_fiemap,
|
||
|
};
|
||
|
|