165 строки
4.4 KiB
C
165 строки
4.4 KiB
C
/*
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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/jbd2.h>
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#include <linux/mount.h>
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#include <linux/path.h>
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#include <linux/quotaops.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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/*
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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 ssize_t
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ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
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unsigned long nr_segs, loff_t pos)
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{
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struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
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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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size_t length = iov_length(iov, nr_segs);
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if (pos > sbi->s_bitmap_maxbytes)
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return -EFBIG;
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if (pos + length > sbi->s_bitmap_maxbytes) {
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nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
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sbi->s_bitmap_maxbytes - pos);
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}
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}
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return generic_file_aio_write(iocb, iov, nr_segs, pos);
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}
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static const struct vm_operations_struct ext4_file_vm_ops = {
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.fault = filemap_fault,
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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 address_space *mapping = file->f_mapping;
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if (!mapping->a_ops->readpage)
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return -ENOEXEC;
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file_accessed(file);
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vma->vm_ops = &ext4_file_vm_ops;
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vma->vm_flags |= VM_CAN_NONLINEAR;
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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 path path;
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char buf[64], *cp;
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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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memcpy(sbi->s_es->s_last_mounted, cp,
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sizeof(sbi->s_es->s_last_mounted));
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sb->s_dirt = 1;
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}
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}
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return dquot_file_open(inode, filp);
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}
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const struct file_operations ext4_file_operations = {
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.llseek = generic_file_llseek,
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.read = do_sync_read,
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.write = do_sync_write,
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.aio_read = generic_file_aio_read,
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.aio_write = ext4_file_write,
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.unlocked_ioctl = ext4_ioctl,
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#ifdef CONFIG_COMPAT
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.compat_ioctl = ext4_compat_ioctl,
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#endif
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.mmap = ext4_file_mmap,
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.open = ext4_file_open,
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.release = ext4_release_file,
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.fsync = ext4_sync_file,
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.splice_read = generic_file_splice_read,
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.splice_write = generic_file_splice_write,
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};
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const struct inode_operations ext4_file_inode_operations = {
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.truncate = ext4_truncate,
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.setattr = ext4_setattr,
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.getattr = ext4_getattr,
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#ifdef CONFIG_EXT4_FS_XATTR
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.setxattr = generic_setxattr,
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.getxattr = generic_getxattr,
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.listxattr = ext4_listxattr,
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.removexattr = generic_removexattr,
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#endif
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.check_acl = ext4_check_acl,
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.fallocate = ext4_fallocate,
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.fiemap = ext4_fiemap,
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};
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