C++ V9FS_I函数代码示例

/**
 * v9fs_clear_inode - release an inode
 * @inode: inode to release
 *
 */
void v9fs_evict_inode(struct inode *inode)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);

	truncate_inode_pages(inode->i_mapping, 0);
	end_writeback(inode);
	filemap_fdatawrite(inode->i_mapping);

#ifdef CONFIG_9P_FSCACHE
	v9fs_cache_inode_put_cookie(inode);
#endif
	/* clunk the fid stashed in writeback_fid */
	if (v9inode->writeback_fid) {
		p9_client_clunk(v9inode->writeback_fid);
		v9inode->writeback_fid = NULL;
	}
}

void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);
	struct p9_fid *fid;

	if (!v9inode->fscache)
		return;

	spin_lock(&v9inode->fscache_lock);
	fid = filp->private_data;
	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
		v9fs_cache_inode_flush_cookie(inode);
	else
		v9fs_cache_inode_get_cookie(inode);

	spin_unlock(&v9inode->fscache_lock);
}

static int v9fs_write_inode(struct inode *inode,
			    struct writeback_control *wbc)
{
	int ret;
	struct p9_wstat wstat;
	struct v9fs_inode *v9inode;
	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
	v9inode = V9FS_I(inode);
	if (!v9inode->writeback_fid)
		return 0;
	v9fs_blank_wstat(&wstat);

	ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
	if (ret < 0) {
		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
		return ret;
	}
	return 0;
}

void v9fs_cache_inode_get_cookie(struct inode *inode)
{
	struct v9fs_inode *v9inode;
	struct v9fs_session_info *v9ses;

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

	v9inode = V9FS_I(inode);
	if (v9inode->fscache)
		return;

	v9ses = v9fs_inode2v9ses(inode);
	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
						  &v9fs_cache_inode_index_def,
						  v9inode);

	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
		 inode, v9inode->fscache);
}

static int v9fs_write_inode_dotl(struct inode *inode,
				 struct writeback_control *wbc)
{
	int ret;
	struct v9fs_inode *v9inode;
	/*
	 * send an fsync request to server irrespective of
	 * wbc->sync_mode.
	 */
	P9_DPRINTK(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
	v9inode = V9FS_I(inode);
	if (!v9inode->writeback_fid)
		return 0;
	ret = p9_client_fsync(v9inode->writeback_fid, 0);
	if (ret < 0) {
		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
		return ret;
	}
	return 0;
}

static int v9fs_test_inode_dotl(struct inode *inode, void *data)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);
	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;

	/* don't match inode of different type */
	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
		return 0;

	if (inode->i_generation != st->st_gen)
		return 0;

	/* compare qid details */
	if (memcmp(&v9inode->qid.version,
		   &st->qid.version, sizeof(v9inode->qid.version)))
		return 0;

	if (v9inode->qid.type != st->qid.type)
		return 0;
	return 1;
}

static int v9fs_test_inode(struct inode *inode, void *data)
{
	int umode;
	struct v9fs_inode *v9inode = V9FS_I(inode);
	struct p9_wstat *st = (struct p9_wstat *)data;
	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);

	umode = p9mode2unixmode(v9ses, st->mode);
	/* don't match inode of different type */
	if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
		return 0;

	/* compare qid details */
	if (memcmp(&v9inode->qid.version,
		   &st->qid.version, sizeof(v9inode->qid.version)))
		return 0;

	if (v9inode->qid.type != st->qid.type)
		return 0;
	return 1;
}

void v9fs_cache_inode_reset_cookie(struct inode *inode)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);
	struct v9fs_session_info *v9ses;
	struct fscache_cookie *old;

	if (!v9inode->fscache)
		return;

	old = v9inode->fscache;

	spin_lock(&v9inode->fscache_lock);
	fscache_relinquish_cookie(v9inode->fscache, 1);

	v9ses = v9fs_inode2v9ses(inode);
	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
						  &v9fs_cache_inode_index_def,
						  v9inode);
	p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
		 inode, old, v9inode->fscache);

	spin_unlock(&v9inode->fscache_lock);
}

static int
v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
{
	int retval;
	struct inode *inode;
	struct v9fs_inode *v9inode;
	struct p9_fid *fid;

	inode = file_inode(filp);
	v9inode = V9FS_I(inode);
	mutex_lock(&v9inode->v_mutex);
	if (!v9inode->writeback_fid &&
	    (vma->vm_flags & VM_WRITE)) {
		/*
		 * clone a fid and add it to writeback_fid
		 * we do it during mmap instead of
		 * page dirty time via write_begin/page_mkwrite
		 * because we want write after unlink usecase
		 * to work.
		 */
		fid = v9fs_writeback_fid(file_dentry(filp));
		if (IS_ERR(fid)) {
			retval = PTR_ERR(fid);
			mutex_unlock(&v9inode->v_mutex);
			return retval;
		}
		v9inode->writeback_fid = (void *) fid;
	}
	mutex_unlock(&v9inode->v_mutex);

	retval = generic_file_mmap(filp, vma);
	if (!retval)
		vma->vm_ops = &v9fs_mmap_file_vm_ops;

	return retval;
}

static void v9fs_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	INIT_LIST_HEAD(&inode->i_dentry);
	kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
}

static void v9fs_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
}

void
v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);

	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
		inode->i_atime.tv_sec = stat->st_atime_sec;
		inode->i_atime.tv_nsec = stat->st_atime_nsec;
		inode->i_mtime.tv_sec = stat->st_mtime_sec;
		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
		inode->i_ctime.tv_sec = stat->st_ctime_sec;
		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
		inode->i_uid = stat->st_uid;
		inode->i_gid = stat->st_gid;
		inode->i_nlink = stat->st_nlink;
		inode->i_mode = stat->st_mode;
		inode->i_rdev = new_decode_dev(stat->st_rdev);

		if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode)))
			init_special_inode(inode, inode->i_mode, inode->i_rdev);

		i_size_write(inode, stat->st_size);
		inode->i_blocks = stat->st_blocks;
	} else {
		if (stat->st_result_mask & P9_STATS_ATIME) {
			inode->i_atime.tv_sec = stat->st_atime_sec;
			inode->i_atime.tv_nsec = stat->st_atime_nsec;
		}
		if (stat->st_result_mask & P9_STATS_MTIME) {
			inode->i_mtime.tv_sec = stat->st_mtime_sec;
			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
		}
		if (stat->st_result_mask & P9_STATS_CTIME) {
			inode->i_ctime.tv_sec = stat->st_ctime_sec;
			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
		}
		if (stat->st_result_mask & P9_STATS_UID)
			inode->i_uid = stat->st_uid;
		if (stat->st_result_mask & P9_STATS_GID)
			inode->i_gid = stat->st_gid;
		if (stat->st_result_mask & P9_STATS_NLINK)
			inode->i_nlink = stat->st_nlink;
		if (stat->st_result_mask & P9_STATS_MODE) {
			inode->i_mode = stat->st_mode;
			if ((S_ISBLK(inode->i_mode)) ||
						(S_ISCHR(inode->i_mode)))
				init_special_inode(inode, inode->i_mode,
								inode->i_rdev);
		}
		if (stat->st_result_mask & P9_STATS_RDEV)
			inode->i_rdev = new_decode_dev(stat->st_rdev);
		if (stat->st_result_mask & P9_STATS_SIZE)
			i_size_write(inode, stat->st_size);
		if (stat->st_result_mask & P9_STATS_BLOCKS)
			inode->i_blocks = stat->st_blocks;
	}
	if (stat->st_result_mask & P9_STATS_GEN)
			inode->i_generation = stat->st_gen;

	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
	 * because the inode structure does not have fields for them.
	 */
	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
}

static int
v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
		struct nameidata *nd)
{
	int err = 0;
	gid_t gid;
	int flags;
	mode_t mode;
	char *name = NULL;
	struct file *filp;
	struct p9_qid qid;
	struct inode *inode;
	struct p9_fid *fid = NULL;
	struct v9fs_inode *v9inode;
	struct p9_fid *dfid, *ofid, *inode_fid;
	struct v9fs_session_info *v9ses;
	struct posix_acl *pacl = NULL, *dacl = NULL;

	v9ses = v9fs_inode2v9ses(dir);
	if (nd && nd->flags & LOOKUP_OPEN)
		flags = nd->intent.open.flags - 1;
	else {
		/*
		 * create call without LOOKUP_OPEN is due
		 * to mknod of regular files. So use mknod
		 * operation.
		 */
		return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
	}

	name = (char *) dentry->d_name.name;
	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
			"mode:0x%x\n", name, flags, omode);

	dfid = v9fs_fid_lookup(dentry->d_parent);
	if (IS_ERR(dfid)) {
		err = PTR_ERR(dfid);
		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
		return err;
	}

	/* clone a fid to use for creation */
	ofid = p9_client_walk(dfid, 0, NULL, 1);
	if (IS_ERR(ofid)) {
		err = PTR_ERR(ofid);
		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
		return err;
	}

	gid = v9fs_get_fsgid_for_create(dir);

	mode = omode;
	/* Update mode based on ACL value */
	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
	if (err) {
		P9_DPRINTK(P9_DEBUG_VFS,
			   "Failed to get acl values in creat %d\n", err);
		goto error;
	}
	err = p9_client_create_dotl(ofid, name, flags, mode, gid, &qid);
	if (err < 0) {
		P9_DPRINTK(P9_DEBUG_VFS,
				"p9_client_open_dotl failed in creat %d\n",
				err);
		goto error;
	}
	v9fs_invalidate_inode_attr(dir);

	/* instantiate inode and assign the unopened fid to the dentry */
	fid = p9_client_walk(dfid, 1, &name, 1);
	if (IS_ERR(fid)) {
		err = PTR_ERR(fid);
		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
		fid = NULL;
		goto error;
	}
	inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
	if (IS_ERR(inode)) {
		err = PTR_ERR(inode);
		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
		goto error;
	}
	d_instantiate(dentry, inode);
	err = v9fs_fid_add(dentry, fid);
	if (err < 0)
		goto error;

	/* Now set the ACL based on the default value */
	v9fs_set_create_acl(dentry, dacl, pacl);

	v9inode = V9FS_I(inode);
	mutex_lock(&v9inode->v_mutex);
	if (v9ses->cache && !v9inode->writeback_fid &&
	    ((flags & O_ACCMODE) != O_RDONLY)) {
		/*
		 * clone a fid and add it to writeback_fid
		 * we do it during open time instead of
		 * page dirty time via write_begin/page_mkwrite
		 * because we want write after unlink usecase
		 * to work.
//.........这里部分代码省略.........