示例#1
0
static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
			const char *symname)
{
	struct gfs2_dinode *di;
	struct buffer_head *dibh;

	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
	gfs2_trans_add_meta(ip->i_gl, dibh);
	di = (struct gfs2_dinode *)dibh->b_data;
	gfs2_dinode_out(ip, di);

	di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
	di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
	di->__pad1 = 0;
	di->__pad2 = 0;
	di->__pad3 = 0;
	memset(&di->__pad4, 0, sizeof(di->__pad4));
	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));

	switch(ip->i_inode.i_mode & S_IFMT) {
	case S_IFDIR:
		gfs2_init_dir(dibh, dip);
		break;
	case S_IFLNK:
		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
		break;
	}

	set_buffer_uptodate(dibh);
	brelse(dibh);
}
示例#2
0
void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
			s64 dinodes)
{
	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
	struct buffer_head *l_bh;
	s64 x, y;
	int need_sync = 0;
	int error;

	error = gfs2_meta_inode_buffer(l_ip, &l_bh);
	if (error)
		return;

	gfs2_trans_add_meta(l_ip->i_gl, l_bh);

	spin_lock(&sdp->sd_statfs_spin);
	l_sc->sc_total += total;
	l_sc->sc_free += free;
	l_sc->sc_dinodes += dinodes;
	gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
	if (sdp->sd_args.ar_statfs_percent) {
		x = 100 * l_sc->sc_free;
		y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
		if (x >= y || x <= -y)
			need_sync = 1;
	}
	spin_unlock(&sdp->sd_statfs_spin);

	brelse(l_bh);
	if (need_sync)
		gfs2_wake_up_statfs(sdp);
}
示例#3
0
文件: bmap.c 项目: 383530895/linux
int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
{
	struct buffer_head *bh, *dibh;
	struct gfs2_dinode *di;
	u64 block = 0;
	int isdir = gfs2_is_dir(ip);
	int error;

	down_write(&ip->i_rw_mutex);

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out;

	if (i_size_read(&ip->i_inode)) {
		/* Get a free block, fill it with the stuffed data,
		   and write it out to disk */

		unsigned int n = 1;
		error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL);
		if (error)
			goto out_brelse;
		if (isdir) {
			gfs2_trans_add_unrevoke(GFS2_SB(&ip->i_inode), block, 1);
			error = gfs2_dir_get_new_buffer(ip, block, &bh);
			if (error)
				goto out_brelse;
			gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header),
					      dibh, sizeof(struct gfs2_dinode));
			brelse(bh);
		} else {
			error = gfs2_unstuffer_page(ip, dibh, block, page);
			if (error)
				goto out_brelse;
		}
	}

	/*  Set up the pointer to the new block  */

	gfs2_trans_add_meta(ip->i_gl, dibh);
	di = (struct gfs2_dinode *)dibh->b_data;
	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));

	if (i_size_read(&ip->i_inode)) {
		*(__be64 *)(di + 1) = cpu_to_be64(block);
		gfs2_add_inode_blocks(&ip->i_inode, 1);
		di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
	}

	ip->i_height = 1;
	di->di_height = cpu_to_be16(1);

out_brelse:
	brelse(dibh);
out:
	up_write(&ip->i_rw_mutex);
	return error;
}
示例#4
0
static int gfs2_write_end(struct file *file, struct address_space *mapping,
			  loff_t pos, unsigned len, unsigned copied,
			  struct page *page, void *fsdata)
{
	struct inode *inode = page->mapping->host;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct buffer_head *dibh;
	unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
	unsigned int to = from + len;
	int ret;
	struct gfs2_trans *tr = current->journal_info;
	BUG_ON(!tr);

	BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == NULL);

	ret = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(ret)) {
		unlock_page(page);
		page_cache_release(page);
		goto failed;
	}

	if (gfs2_is_stuffed(ip))
		return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);

	if (!gfs2_is_writeback(ip))
		gfs2_page_add_databufs(ip, page, from, to);

	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
	if (tr->tr_num_buf_new)
		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
	else
		gfs2_trans_add_meta(ip->i_gl, dibh);


	if (inode == sdp->sd_rindex) {
		adjust_fs_space(inode);
		sdp->sd_rindex_uptodate = 0;
	}

	brelse(dibh);
failed:
	gfs2_trans_end(sdp);
	gfs2_inplace_release(ip);
	if (ip->i_res->rs_qa_qd_num)
		gfs2_quota_unlock(ip);
	if (inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
	gfs2_holder_uninit(&ip->i_gh);
	return ret;
}
示例#5
0
void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
		   struct buffer_head *l_bh)
{
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;

	gfs2_trans_add_meta(l_ip->i_gl, l_bh);
	gfs2_trans_add_meta(m_ip->i_gl, m_bh);

	spin_lock(&sdp->sd_statfs_spin);
	m_sc->sc_total += l_sc->sc_total;
	m_sc->sc_free += l_sc->sc_free;
	m_sc->sc_dinodes += l_sc->sc_dinodes;
	memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
	memset(l_bh->b_data + sizeof(struct gfs2_dinode),
	       0, sizeof(struct gfs2_statfs_change));
	gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
	spin_unlock(&sdp->sd_statfs_spin);
}
示例#6
0
文件: bmap.c 项目: 383530895/linux
static inline __be64 *gfs2_indirect_init(struct metapath *mp,
					 struct gfs2_glock *gl, unsigned int i,
					 unsigned offset, u64 bn)
{
	__be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data +
		       ((i > 1) ? sizeof(struct gfs2_meta_header) :
				 sizeof(struct gfs2_dinode)));
	BUG_ON(i < 1);
	BUG_ON(mp->mp_bh[i] != NULL);
	mp->mp_bh[i] = gfs2_meta_new(gl, bn);
	gfs2_trans_add_meta(gl, mp->mp_bh[i]);
	gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
	gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header));
	ptr += offset;
	*ptr = cpu_to_be64(bn);
	return ptr;
}
示例#7
0
static void gfs2_init_xattr(struct gfs2_inode *ip)
{
	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	struct buffer_head *bh;
	struct gfs2_ea_header *ea;

	bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
	gfs2_trans_add_meta(ip->i_gl, bh);
	gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));

	ea = GFS2_EA_BH2FIRST(bh);
	ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
	ea->ea_type = GFS2_EATYPE_UNUSED;
	ea->ea_flags = GFS2_EAFLAG_LAST;

	brelse(bh);
}
示例#8
0
static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
		       struct gfs2_inode *ip)
{
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	int alloc_required;
	struct buffer_head *dibh;
	int error;

	error = gfs2_rindex_update(sdp);
	if (error)
		return error;

	error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
	if (error)
		goto fail;

	error = alloc_required = gfs2_diradd_alloc_required(&dip->i_inode, name);
	if (alloc_required < 0)
		goto fail_quota_locks;
	if (alloc_required) {
		error = gfs2_quota_check(dip, dip->i_inode.i_uid, dip->i_inode.i_gid);
		if (error)
			goto fail_quota_locks;

		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
		if (error)
			goto fail_quota_locks;

		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
					 dip->i_rgd->rd_length +
					 2 * RES_DINODE +
					 RES_STATFS + RES_QUOTA, 0);
		if (error)
			goto fail_ipreserv;
	} else {
		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
		if (error)
			goto fail_quota_locks;
	}

	error = gfs2_dir_add(&dip->i_inode, name, ip);
	if (error)
		goto fail_end_trans;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto fail_end_trans;
	set_nlink(&ip->i_inode, S_ISDIR(ip->i_inode.i_mode) ? 2 : 1);
	gfs2_trans_add_meta(ip->i_gl, dibh);
	gfs2_dinode_out(ip, dibh->b_data);
	brelse(dibh);
	return 0;

fail_end_trans:
	gfs2_trans_end(sdp);

fail_ipreserv:
	if (alloc_required)
		gfs2_inplace_release(dip);

fail_quota_locks:
	gfs2_quota_unlock(dip);

fail:
	return error;
}
示例#9
0
static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
		       struct gfs2_inode *ip, struct gfs2_diradd *da)
{
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
	int error;

	if (da->nr_blocks) {
		error = gfs2_quota_lock_check(dip, &ap);
		if (error)
			goto fail_quota_locks;

		error = gfs2_inplace_reserve(dip, &ap);
		if (error)
			goto fail_quota_locks;

		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
		if (error)
			goto fail_ipreserv;
	} else {
		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
		if (error)
			goto fail_quota_locks;
	}

	error = gfs2_dir_add(&dip->i_inode, name, ip, da);

	gfs2_trans_end(sdp);
fail_ipreserv:
	gfs2_inplace_release(dip);
fail_quota_locks:
	gfs2_quota_unlock(dip);
	return error;
}

static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
		    void *fs_info)
{
	const struct xattr *xattr;
	int err = 0;

	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
				       xattr->value_len, 0,
				       GFS2_EATYPE_SECURITY);
		if (err < 0)
			break;
	}
	return err;
}

/**
 * gfs2_create_inode - Create a new inode
 * @dir: The parent directory
 * @dentry: The new dentry
 * @file: If non-NULL, the file which is being opened
 * @mode: The permissions on the new inode
 * @dev: For device nodes, this is the device number
 * @symname: For symlinks, this is the link destination
 * @size: The initial size of the inode (ignored for directories)
 *
 * Returns: 0 on success, or error code
 */

static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
			     struct file *file,
			     umode_t mode, dev_t dev, const char *symname,
			     unsigned int size, int excl)
{
	const struct qstr *name = &dentry->d_name;
	struct posix_acl *default_acl, *acl;
	struct gfs2_holder ghs[2];
	struct inode *inode = NULL;
	struct gfs2_inode *dip = GFS2_I(dir), *ip;
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_glock *io_gl = NULL;
	int error, free_vfs_inode = 1;
	u32 aflags = 0;
	unsigned blocks = 1;
	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };

	if (!name->len || name->len > GFS2_FNAMESIZE)
		return -ENAMETOOLONG;

	error = gfs2_rsqa_alloc(dip);
	if (error)
		return error;

	error = gfs2_rindex_update(sdp);
	if (error)
		return error;

	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	if (error)
		goto fail;
	gfs2_holder_mark_uninitialized(ghs + 1);

	error = create_ok(dip, name, mode);
	if (error)
		goto fail_gunlock;

	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
	error = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		if (S_ISDIR(inode->i_mode)) {
			iput(inode);
			inode = ERR_PTR(-EISDIR);
			goto fail_gunlock;
		}
		d_instantiate(dentry, inode);
		error = 0;
		if (file) {
			if (S_ISREG(inode->i_mode))
				error = finish_open(file, dentry, gfs2_open_common);
			else
				error = finish_no_open(file, NULL);
		}
		gfs2_glock_dq_uninit(ghs);
		return error;
	} else if (error != -ENOENT) {
		goto fail_gunlock;
	}

	error = gfs2_diradd_alloc_required(dir, name, &da);
	if (error < 0)
		goto fail_gunlock;

	inode = new_inode(sdp->sd_vfs);
	error = -ENOMEM;
	if (!inode)
		goto fail_gunlock;

	error = posix_acl_create(dir, &mode, &default_acl, &acl);
	if (error)
		goto fail_gunlock;

	ip = GFS2_I(inode);
	error = gfs2_rsqa_alloc(ip);
	if (error)
		goto fail_free_acls;

	inode->i_mode = mode;
	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
	inode->i_rdev = dev;
	inode->i_size = size;
	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
	gfs2_set_inode_blocks(inode, 1);
	munge_mode_uid_gid(dip, inode);
	check_and_update_goal(dip);
	ip->i_goal = dip->i_goal;
	ip->i_diskflags = 0;
	ip->i_eattr = 0;
	ip->i_height = 0;
	ip->i_depth = 0;
	ip->i_entries = 0;
	ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */

	switch(mode & S_IFMT) {
	case S_IFREG:
		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
		    gfs2_tune_get(sdp, gt_new_files_jdata))
			ip->i_diskflags |= GFS2_DIF_JDATA;
		gfs2_set_aops(inode);
		break;
	case S_IFDIR:
		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
		ip->i_diskflags |= GFS2_DIF_JDATA;
		ip->i_entries = 2;
		break;
	}

	/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
	if (dip->i_diskflags & GFS2_DIF_SYSTEM)
		ip->i_diskflags |= GFS2_DIF_SYSTEM;

	gfs2_set_inode_flags(inode);

	if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
		aflags |= GFS2_AF_ORLOV;

	if (default_acl || acl)
		blocks++;

	error = alloc_dinode(ip, aflags, &blocks);
	if (error)
		goto fail_free_inode;

	gfs2_set_inode_blocks(inode, blocks);

	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
	if (error)
		goto fail_free_inode;
	flush_delayed_work(&ip->i_gl->gl_work);
	glock_set_object(ip->i_gl, ip);

	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
	if (error)
		goto fail_free_inode;

	error = gfs2_trans_begin(sdp, blocks, 0);
	if (error)
		goto fail_gunlock2;

	if (blocks > 1) {
		ip->i_eattr = ip->i_no_addr + 1;
		gfs2_init_xattr(ip);
	}
	init_dinode(dip, ip, symname);
	gfs2_trans_end(sdp);

	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
	if (error)
		goto fail_gunlock2;

	BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags));

	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
	if (error)
		goto fail_gunlock2;

	glock_set_object(ip->i_iopen_gh.gh_gl, ip);
	gfs2_glock_put(io_gl);
	gfs2_set_iop(inode);
	insert_inode_hash(inode);

	free_vfs_inode = 0; /* After this point, the inode is no longer
			       considered free. Any failures need to undo
			       the gfs2 structures. */
	if (default_acl) {
		error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
		if (error)
			goto fail_gunlock3;
		posix_acl_release(default_acl);
		default_acl = NULL;
	}
	if (acl) {
		error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
		if (error)
			goto fail_gunlock3;
		posix_acl_release(acl);
		acl = NULL;
	}

	error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
					     &gfs2_initxattrs, NULL);
	if (error)
		goto fail_gunlock3;

	error = link_dinode(dip, name, ip, &da);
	if (error)
		goto fail_gunlock3;

	mark_inode_dirty(inode);
	d_instantiate(dentry, inode);
	if (file) {
		file->f_mode |= FMODE_CREATED;
		error = finish_open(file, dentry, gfs2_open_common);
	}
	gfs2_glock_dq_uninit(ghs);
	gfs2_glock_dq_uninit(ghs + 1);
	clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
	return error;

fail_gunlock3:
	glock_clear_object(io_gl, ip);
	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
	gfs2_glock_put(io_gl);
fail_gunlock2:
	if (io_gl)
		clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
fail_free_inode:
	if (ip->i_gl) {
		glock_clear_object(ip->i_gl, ip);
		gfs2_glock_put(ip->i_gl);
	}
	gfs2_rsqa_delete(ip, NULL);
fail_free_acls:
	posix_acl_release(default_acl);
	posix_acl_release(acl);
fail_gunlock:
	gfs2_dir_no_add(&da);
	gfs2_glock_dq_uninit(ghs);
	if (inode && !IS_ERR(inode)) {
		clear_nlink(inode);
		if (!free_vfs_inode)
			mark_inode_dirty(inode);
		set_bit(free_vfs_inode ? GIF_FREE_VFS_INODE : GIF_ALLOC_FAILED,
			&GFS2_I(inode)->i_flags);
		iput(inode);
	}
	if (gfs2_holder_initialized(ghs + 1))
		gfs2_glock_dq_uninit(ghs + 1);
fail:
	return error;
}

/**
 * gfs2_create - Create a file
 * @dir: The directory in which to create the file
 * @dentry: The dentry of the new file
 * @mode: The mode of the new file
 *
 * Returns: errno
 */

static int gfs2_create(struct inode *dir, struct dentry *dentry,
		       umode_t mode, bool excl)
{
	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
}

/**
 * __gfs2_lookup - Look up a filename in a directory and return its inode
 * @dir: The directory inode
 * @dentry: The dentry of the new inode
 * @file: File to be opened
 *
 *
 * Returns: errno
 */

static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
				    struct file *file)
{
	struct inode *inode;
	struct dentry *d;
	struct gfs2_holder gh;
	struct gfs2_glock *gl;
	int error;

	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
	if (inode == NULL) {
		d_add(dentry, NULL);
		return NULL;
	}
	if (IS_ERR(inode))
		return ERR_CAST(inode);

	gl = GFS2_I(inode)->i_gl;
	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
	if (error) {
		iput(inode);
		return ERR_PTR(error);
	}

	d = d_splice_alias(inode, dentry);
	if (IS_ERR(d)) {
		gfs2_glock_dq_uninit(&gh);
		return d;
	}
	if (file && S_ISREG(inode->i_mode))
		error = finish_open(file, dentry, gfs2_open_common);

	gfs2_glock_dq_uninit(&gh);
	if (error) {
		dput(d);
		return ERR_PTR(error);
	}
	return d;
}

static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
				  unsigned flags)
{
	return __gfs2_lookup(dir, dentry, NULL);
}

/**
 * gfs2_link - Link to a file
 * @old_dentry: The inode to link
 * @dir: Add link to this directory
 * @dentry: The name of the link
 *
 * Link the inode in "old_dentry" into the directory "dir" with the
 * name in "dentry".
 *
 * Returns: errno
 */

static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = d_inode(old_dentry);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	struct buffer_head *dibh;
	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
	int error;

	if (S_ISDIR(inode->i_mode))
		return -EPERM;

	error = gfs2_rsqa_alloc(dip);
	if (error)
		return error;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_gunlock;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
	if (error < 0)
		goto out_gunlock;

	if (da.nr_blocks) {
		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
		error = gfs2_quota_lock_check(dip, &ap);
		if (error)
			goto out_gunlock;

		error = gfs2_inplace_reserve(dip, &ap);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out_end_trans;

	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
	if (error)
		goto out_brelse;

	gfs2_trans_add_meta(ip->i_gl, dibh);
	inc_nlink(&ip->i_inode);
	ip->i_inode.i_ctime = current_time(&ip->i_inode);
	ihold(inode);
	d_instantiate(dentry, inode);
	mark_inode_dirty(inode);

out_brelse:
	brelse(dibh);
out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (da.nr_blocks)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (da.nr_blocks)
		gfs2_quota_unlock(dip);
out_gunlock:
	gfs2_dir_no_add(&da);
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	return error;
}

/*
 * gfs2_unlink_ok - check to see that a inode is still in a directory
 * @dip: the directory
 * @name: the name of the file
 * @ip: the inode
 *
 * Assumes that the lock on (at least) @dip is held.
 *
 * Returns: 0 if the parent/child relationship is correct, errno if it isn't
 */

static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
			  const struct gfs2_inode *ip)
{
	int error;

	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
		return -EPERM;

	if ((dip->i_inode.i_mode & S_ISVTX) &&
	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
		return -EPERM;

	if (IS_APPEND(&dip->i_inode))
		return -EPERM;

	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;

	return gfs2_dir_check(&dip->i_inode, name, ip);
}

/**
 * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
 * @dip: The parent directory
 * @name: The name of the entry in the parent directory
 * @inode: The inode to be removed
 *
 * Called with all the locks and in a transaction. This will only be
 * called for a directory after it has been checked to ensure it is empty.
 *
 * Returns: 0 on success, or an error
 */

static int gfs2_unlink_inode(struct gfs2_inode *dip,
			     const struct dentry *dentry)
{
	struct inode *inode = d_inode(dentry);
	struct gfs2_inode *ip = GFS2_I(inode);
	int error;

	error = gfs2_dir_del(dip, dentry);
	if (error)
		return error;

	ip->i_entries = 0;
	inode->i_ctime = current_time(inode);
	if (S_ISDIR(inode->i_mode))
		clear_nlink(inode);
	else
		drop_nlink(inode);
	mark_inode_dirty(inode);
	if (inode->i_nlink == 0)
		gfs2_unlink_di(inode);
	return 0;
}


/**
 * gfs2_unlink - Unlink an inode (this does rmdir as well)
 * @dir: The inode of the directory containing the inode to unlink
 * @dentry: The file itself
 *
 * This routine uses the type of the inode as a flag to figure out
 * whether this is an unlink or an rmdir.
 *
 * Returns: errno
 */

static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = d_inode(dentry);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[3];
	struct gfs2_rgrpd *rgd;
	int error;

	error = gfs2_rindex_update(sdp);
	if (error)
		return error;

	error = -EROFS;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);

	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
	if (!rgd)
		goto out_inodes;

	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);


	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_rgrp;

	if (S_ISDIR(inode->i_mode)) {
		error = -ENOTEMPTY;
		if (ip->i_entries > 2 || inode->i_nlink > 2)
			goto out_rgrp;
	}

	error = gfs2_glock_nq(ghs + 2); /* rgrp */
	if (error)
		goto out_rgrp;

	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
	if (error)
		goto out_gunlock;

	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
	if (error)
		goto out_gunlock;

	error = gfs2_unlink_inode(dip, dentry);
	gfs2_trans_end(sdp);

out_gunlock:
	gfs2_glock_dq(ghs + 2);
out_rgrp:
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs + 2);
out_inodes:
	gfs2_holder_uninit(ghs + 1);
	gfs2_holder_uninit(ghs);
	return error;
}

/**
 * gfs2_symlink - Create a symlink
 * @dir: The directory to create the symlink in
 * @dentry: The dentry to put the symlink in
 * @symname: The thing which the link points to
 *
 * Returns: errno
 */

static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
			const char *symname)
{
	unsigned int size;

	size = strlen(symname);
	if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
		return -ENAMETOOLONG;

	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
}

/**
 * gfs2_mkdir - Make a directory
 * @dir: The parent directory of the new one
 * @dentry: The dentry of the new directory
 * @mode: The mode of the new directory
 *
 * Returns: errno
 */

static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
}
static int gfs2_write_begin(struct file *file, struct address_space *mapping,
			    loff_t pos, unsigned len, unsigned flags,
			    struct page **pagep, void **fsdata)
{
	struct gfs2_inode *ip = GFS2_I(mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	unsigned requested = 0;
	int alloc_required;
	int error = 0;
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	unsigned from = pos & (PAGE_CACHE_SIZE - 1);
	struct page *page;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
	error = gfs2_glock_nq(&ip->i_gh);
	if (unlikely(error))
		goto out_uninit;
	if (&ip->i_inode == sdp->sd_rindex) {
		error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
					   GL_NOCACHE, &m_ip->i_gh);
		if (unlikely(error)) {
			gfs2_glock_dq(&ip->i_gh);
			goto out_uninit;
		}
	}

	alloc_required = gfs2_write_alloc_required(ip, pos, len);

	if (alloc_required || gfs2_is_jdata(ip))
		gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);

	if (alloc_required) {
		struct gfs2_alloc_parms ap = { .aflags = 0, };
		requested = data_blocks + ind_blocks;
		ap.target = requested;
		error = gfs2_quota_lock_check(ip, &ap);
		if (error)
			goto out_unlock;

		error = gfs2_inplace_reserve(ip, &ap);
		if (error)
			goto out_qunlock;
	}

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks)
		rblocks += RES_STATFS + RES_QUOTA;
	if (&ip->i_inode == sdp->sd_rindex)
		rblocks += 2 * RES_STATFS;
	if (alloc_required)
		rblocks += gfs2_rg_blocks(ip, requested);

	error = gfs2_trans_begin(sdp, rblocks,
				 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
	if (error)
		goto out_trans_fail;

	error = -ENOMEM;
	flags |= AOP_FLAG_NOFS;
	page = grab_cache_page_write_begin(mapping, index, flags);
	*pagep = page;
	if (unlikely(!page))
		goto out_endtrans;

	if (gfs2_is_stuffed(ip)) {
		error = 0;
		if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
			error = gfs2_unstuff_dinode(ip, page);
			if (error == 0)
				goto prepare_write;
		} else if (!PageUptodate(page)) {
			error = stuffed_readpage(ip, page);
		}
		goto out;
	}

prepare_write:
	error = __block_write_begin(page, from, len, gfs2_block_map);
out:
	if (error == 0)
		return 0;

	unlock_page(page);
	page_cache_release(page);

	gfs2_trans_end(sdp);
	if (pos + len > ip->i_inode.i_size)
		gfs2_trim_blocks(&ip->i_inode);
	goto out_trans_fail;

out_endtrans:
	gfs2_trans_end(sdp);
out_trans_fail:
	if (alloc_required) {
		gfs2_inplace_release(ip);
out_qunlock:
		gfs2_quota_unlock(ip);
	}
out_unlock:
	if (&ip->i_inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_gh);
	return error;
}

/**
 * adjust_fs_space - Adjusts the free space available due to gfs2_grow
 * @inode: the rindex inode
 */
static void adjust_fs_space(struct inode *inode)
{
	struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
	struct buffer_head *m_bh, *l_bh;
	u64 fs_total, new_free;

	/* Total up the file system space, according to the latest rindex. */
	fs_total = gfs2_ri_total(sdp);
	if (gfs2_meta_inode_buffer(m_ip, &m_bh) != 0)
		return;

	spin_lock(&sdp->sd_statfs_spin);
	gfs2_statfs_change_in(m_sc, m_bh->b_data +
			      sizeof(struct gfs2_dinode));
	if (fs_total > (m_sc->sc_total + l_sc->sc_total))
		new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
	else
		new_free = 0;
	spin_unlock(&sdp->sd_statfs_spin);
	fs_warn(sdp, "File system extended by %llu blocks.\n",
		(unsigned long long)new_free);
	gfs2_statfs_change(sdp, new_free, new_free, 0);

	if (gfs2_meta_inode_buffer(l_ip, &l_bh) != 0)
		goto out;
	update_statfs(sdp, m_bh, l_bh);
	brelse(l_bh);
out:
	brelse(m_bh);
}

/**
 * gfs2_stuffed_write_end - Write end for stuffed files
 * @inode: The inode
 * @dibh: The buffer_head containing the on-disk inode
 * @pos: The file position
 * @len: The length of the write
 * @copied: How much was actually copied by the VFS
 * @page: The page
 *
 * This copies the data from the page into the inode block after
 * the inode data structure itself.
 *
 * Returns: errno
 */
static int gfs2_stuffed_write_end(struct inode *inode, struct buffer_head *dibh,
				  loff_t pos, unsigned len, unsigned copied,
				  struct page *page)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	u64 to = pos + copied;
	void *kaddr;
	unsigned char *buf = dibh->b_data + sizeof(struct gfs2_dinode);

	BUG_ON((pos + len) > (dibh->b_size - sizeof(struct gfs2_dinode)));
	kaddr = kmap_atomic(page);
	memcpy(buf + pos, kaddr + pos, copied);
	memset(kaddr + pos + copied, 0, len - copied);
	flush_dcache_page(page);
	kunmap_atomic(kaddr);

	if (!PageUptodate(page))
		SetPageUptodate(page);
	unlock_page(page);
	page_cache_release(page);

	if (copied) {
		if (inode->i_size < to)
			i_size_write(inode, to);
		mark_inode_dirty(inode);
	}

	if (inode == sdp->sd_rindex) {
		adjust_fs_space(inode);
		sdp->sd_rindex_uptodate = 0;
	}

	brelse(dibh);
	gfs2_trans_end(sdp);
	if (inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
	gfs2_holder_uninit(&ip->i_gh);
	return copied;
}

/**
 * gfs2_write_end
 * @file: The file to write to
 * @mapping: The address space to write to
 * @pos: The file position
 * @len: The length of the data
 * @copied:
 * @page: The page that has been written
 * @fsdata: The fsdata (unused in GFS2)
 *
 * The main write_end function for GFS2. We have a separate one for
 * stuffed files as they are slightly different, otherwise we just
 * put our locking around the VFS provided functions.
 *
 * Returns: errno
 */

static int gfs2_write_end(struct file *file, struct address_space *mapping,
			  loff_t pos, unsigned len, unsigned copied,
			  struct page *page, void *fsdata)
{
	struct inode *inode = page->mapping->host;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
	struct buffer_head *dibh;
	unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
	unsigned int to = from + len;
	int ret;
	struct gfs2_trans *tr = current->journal_info;
	BUG_ON(!tr);

	BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == NULL);

	ret = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(ret)) {
		unlock_page(page);
		page_cache_release(page);
		goto failed;
	}

	if (gfs2_is_stuffed(ip))
		return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);

	if (!gfs2_is_writeback(ip))
		gfs2_page_add_databufs(ip, page, from, to);

	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
	if (tr->tr_num_buf_new)
		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
	else
		gfs2_trans_add_meta(ip->i_gl, dibh);


	if (inode == sdp->sd_rindex) {
		adjust_fs_space(inode);
		sdp->sd_rindex_uptodate = 0;
	}

	brelse(dibh);
failed:
	gfs2_trans_end(sdp);
	gfs2_inplace_release(ip);
	if (ip->i_res->rs_qa_qd_num)
		gfs2_quota_unlock(ip);
	if (inode == sdp->sd_rindex) {
		gfs2_glock_dq(&m_ip->i_gh);
		gfs2_holder_uninit(&m_ip->i_gh);
	}
	gfs2_glock_dq(&ip->i_gh);
	gfs2_holder_uninit(&ip->i_gh);
	return ret;
}

/**
 * gfs2_set_page_dirty - Page dirtying function
 * @page: The page to dirty
 *
 * Returns: 1 if it dirtyed the page, or 0 otherwise
 */
 
static int gfs2_set_page_dirty(struct page *page)
{
	SetPageChecked(page);
	return __set_page_dirty_buffers(page);
}
示例#11
0
/**
 * gfs2_set_flags - set flags on an inode
 * @inode: The inode
 * @flags: The flags to set
 * @mask: Indicates which flags are valid
 *
 */
static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
{
	struct inode *inode = filp->f_path.dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct buffer_head *bh;
	struct gfs2_holder gh;
	int error;
	u32 new_flags, flags;

	error = mnt_want_write(filp->f_path.mnt);
	if (error)
		return error;

	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	if (error)
		goto out_drop_write;

	error = -EACCES;
	if (!is_owner_or_cap(inode))
		goto out;

	error = 0;
	flags = ip->i_diskflags;
	new_flags = (flags & ~mask) | (reqflags & mask);
	if ((new_flags ^ flags) == 0)
		goto out;

	error = -EINVAL;
	if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
		goto out;

	error = -EPERM;
	if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
		goto out;
	if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
		goto out;
	if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
	    !capable(CAP_LINUX_IMMUTABLE))
		goto out;
	if (!IS_IMMUTABLE(inode)) {
		error = gfs2_permission(inode, MAY_WRITE);
		if (error)
			goto out;
	}
	if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
		if (flags & GFS2_DIF_JDATA)
			gfs2_log_flush(sdp, ip->i_gl);
		error = filemap_fdatawrite(inode->i_mapping);
		if (error)
			goto out;
		error = filemap_fdatawait(inode->i_mapping);
		if (error)
			goto out;
	}
	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
	if (error)
		goto out;
	error = gfs2_meta_inode_buffer(ip, &bh);
	if (error)
		goto out_trans_end;
	gfs2_trans_add_meta(ip->i_gl, bh);
	ip->i_diskflags = new_flags;
	gfs2_dinode_out(ip, bh->b_data);
	brelse(bh);
	gfs2_set_inode_flags(inode);
	gfs2_set_aops(inode);
out_trans_end:
	gfs2_trans_end(sdp);
out:
	gfs2_glock_dq_uninit(&gh);
out_drop_write:
	mnt_drop_write(filp->f_path.mnt);
	return error;
}
示例#12
0
static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
		       struct gfs2_inode *ip, struct gfs2_diradd *da)
{
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
	int error;

	if (da->nr_blocks) {
		error = gfs2_quota_lock_check(dip);
		if (error)
			goto fail_quota_locks;

		error = gfs2_inplace_reserve(dip, &ap);
		if (error)
			goto fail_quota_locks;

		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
		if (error)
			goto fail_ipreserv;
	} else {
		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
		if (error)
			goto fail_quota_locks;
	}

	error = gfs2_dir_add(&dip->i_inode, name, ip, da);
	if (error)
		goto fail_end_trans;

fail_end_trans:
	gfs2_trans_end(sdp);
fail_ipreserv:
	gfs2_inplace_release(dip);
fail_quota_locks:
	gfs2_quota_unlock(dip);
	return error;
}

static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
		    void *fs_info)
{
	const struct xattr *xattr;
	int err = 0;

	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
				       xattr->value_len, 0,
				       GFS2_EATYPE_SECURITY);
		if (err < 0)
			break;
	}
	return err;
}

static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip,
			      const struct qstr *qstr)
{
	return security_inode_init_security(&ip->i_inode, &dip->i_inode, qstr,
					    &gfs2_initxattrs, NULL);
}

/**
 * gfs2_create_inode - Create a new inode
 * @dir: The parent directory
 * @dentry: The new dentry
 * @file: If non-NULL, the file which is being opened
 * @mode: The permissions on the new inode
 * @dev: For device nodes, this is the device number
 * @symname: For symlinks, this is the link destination
 * @size: The initial size of the inode (ignored for directories)
 *
 * Returns: 0 on success, or error code
 */

static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
			     struct file *file,
			     umode_t mode, dev_t dev, const char *symname,
			     unsigned int size, int excl, int *opened)
{
	const struct qstr *name = &dentry->d_name;
	struct posix_acl *default_acl, *acl;
	struct gfs2_holder ghs[2];
	struct inode *inode = NULL;
	struct gfs2_inode *dip = GFS2_I(dir), *ip;
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_glock *io_gl;
	struct dentry *d;
	int error;
	u32 aflags = 0;
	struct gfs2_diradd da = { .bh = NULL, };

	if (!name->len || name->len > GFS2_FNAMESIZE)
		return -ENAMETOOLONG;

	error = gfs2_rs_alloc(dip);
	if (error)
		return error;

	error = gfs2_rindex_update(sdp);
	if (error)
		return error;

	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	if (error)
		goto fail;

	error = create_ok(dip, name, mode);
	if (error)
		goto fail_gunlock;

	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
	error = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		d = d_splice_alias(inode, dentry);
		error = PTR_ERR(d);
		if (IS_ERR(d)) {
			inode = ERR_CAST(d);
			goto fail_gunlock;
		}
		error = 0;
		if (file) {
			if (S_ISREG(inode->i_mode)) {
				WARN_ON(d != NULL);
				error = finish_open(file, dentry, gfs2_open_common, opened);
			} else {
				error = finish_no_open(file, d);
			}
		} else {
			dput(d);
		}
		gfs2_glock_dq_uninit(ghs);
		return error;
	} else if (error != -ENOENT) {
		goto fail_gunlock;
	}

	error = gfs2_diradd_alloc_required(dir, name, &da);
	if (error < 0)
		goto fail_gunlock;

	inode = new_inode(sdp->sd_vfs);
	error = -ENOMEM;
	if (!inode)
		goto fail_gunlock;

	error = posix_acl_create(dir, &mode, &default_acl, &acl);
	if (error)
		goto fail_free_vfs_inode;

	ip = GFS2_I(inode);
	error = gfs2_rs_alloc(ip);
	if (error)
		goto fail_free_acls;

	inode->i_mode = mode;
	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
	inode->i_rdev = dev;
	inode->i_size = size;
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	gfs2_set_inode_blocks(inode, 1);
	munge_mode_uid_gid(dip, inode);
	ip->i_goal = dip->i_goal;
	ip->i_diskflags = 0;
	ip->i_eattr = 0;
	ip->i_height = 0;
	ip->i_depth = 0;
	ip->i_entries = 0;

	switch(mode & S_IFMT) {
	case S_IFREG:
		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
		    gfs2_tune_get(sdp, gt_new_files_jdata))
			ip->i_diskflags |= GFS2_DIF_JDATA;
		gfs2_set_aops(inode);
		break;
	case S_IFDIR:
		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
		ip->i_diskflags |= GFS2_DIF_JDATA;
		ip->i_entries = 2;
		break;
	}
	gfs2_set_inode_flags(inode);

	if ((GFS2_I(sdp->sd_root_dir->d_inode) == dip) ||
	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
		aflags |= GFS2_AF_ORLOV;

	error = alloc_dinode(ip, aflags);
	if (error)
		goto fail_free_inode;

	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
	if (error)
		goto fail_free_inode;

	ip->i_gl->gl_object = ip;
	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
	if (error)
		goto fail_free_inode;

	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
	if (error)
		goto fail_gunlock2;

	init_dinode(dip, ip, symname);
	gfs2_trans_end(sdp);

	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
	if (error)
		goto fail_gunlock2;

	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
	if (error)
		goto fail_gunlock2;

	ip->i_iopen_gh.gh_gl->gl_object = ip;
	gfs2_glock_put(io_gl);
	gfs2_set_iop(inode);
	insert_inode_hash(inode);

	if (default_acl) {
		error = gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
		posix_acl_release(default_acl);
	}
	if (acl) {
		if (!error)
			error = gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
		posix_acl_release(acl);
	}

	if (error)
		goto fail_gunlock3;

	error = gfs2_security_init(dip, ip, name);
	if (error)
		goto fail_gunlock3;

	error = link_dinode(dip, name, ip, &da);
	if (error)
		goto fail_gunlock3;

	mark_inode_dirty(inode);
	d_instantiate(dentry, inode);
	if (file) {
		*opened |= FILE_CREATED;
		error = finish_open(file, dentry, gfs2_open_common, opened);
	}
	gfs2_glock_dq_uninit(ghs);
	gfs2_glock_dq_uninit(ghs + 1);
	return error;

fail_gunlock3:
	gfs2_glock_dq_uninit(ghs + 1);
	if (ip->i_gl)
		gfs2_glock_put(ip->i_gl);
	goto fail_gunlock;

fail_gunlock2:
	gfs2_glock_dq_uninit(ghs + 1);
fail_free_inode:
	if (ip->i_gl)
		gfs2_glock_put(ip->i_gl);
	gfs2_rs_delete(ip, NULL);
fail_free_acls:
	if (default_acl)
		posix_acl_release(default_acl);
	if (acl)
		posix_acl_release(acl);
fail_free_vfs_inode:
	free_inode_nonrcu(inode);
	inode = NULL;
fail_gunlock:
	gfs2_dir_no_add(&da);
	gfs2_glock_dq_uninit(ghs);
	if (inode && !IS_ERR(inode)) {
		clear_nlink(inode);
		mark_inode_dirty(inode);
		set_bit(GIF_ALLOC_FAILED, &GFS2_I(inode)->i_flags);
		iput(inode);
	}
fail:
	return error;
}

/**
 * gfs2_create - Create a file
 * @dir: The directory in which to create the file
 * @dentry: The dentry of the new file
 * @mode: The mode of the new file
 *
 * Returns: errno
 */

static int gfs2_create(struct inode *dir, struct dentry *dentry,
		       umode_t mode, bool excl)
{
	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl, NULL);
}

/**
 * __gfs2_lookup - Look up a filename in a directory and return its inode
 * @dir: The directory inode
 * @dentry: The dentry of the new inode
 * @file: File to be opened
 * @opened: atomic_open flags
 *
 *
 * Returns: errno
 */

static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
				    struct file *file, int *opened)
{
	struct inode *inode;
	struct dentry *d;
	struct gfs2_holder gh;
	struct gfs2_glock *gl;
	int error;

	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
	if (!inode)
		return NULL;
	if (IS_ERR(inode))
		return ERR_CAST(inode);

	gl = GFS2_I(inode)->i_gl;
	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
	if (error) {
		iput(inode);
		return ERR_PTR(error);
	}

	d = d_splice_alias(inode, dentry);
	if (IS_ERR(d)) {
		gfs2_glock_dq_uninit(&gh);
		return d;
	}
	if (file && S_ISREG(inode->i_mode))
		error = finish_open(file, dentry, gfs2_open_common, opened);

	gfs2_glock_dq_uninit(&gh);
	if (error) {
		dput(d);
		return ERR_PTR(error);
	}
	return d;
}

static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
				  unsigned flags)
{
	return __gfs2_lookup(dir, dentry, NULL, NULL);
}

/**
 * gfs2_link - Link to a file
 * @old_dentry: The inode to link
 * @dir: Add link to this directory
 * @dentry: The name of the link
 *
 * Link the inode in "old_dentry" into the directory "dir" with the
 * name in "dentry".
 *
 * Returns: errno
 */

static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = old_dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	struct buffer_head *dibh;
	struct gfs2_diradd da = { .bh = NULL, };
	int error;

	if (S_ISDIR(inode->i_mode))
		return -EPERM;

	error = gfs2_rs_alloc(dip);
	if (error)
		return error;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_gunlock;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
	if (error < 0)
		goto out_gunlock;

	if (da.nr_blocks) {
		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
		error = gfs2_quota_lock_check(dip);
		if (error)
			goto out_gunlock;

		error = gfs2_inplace_reserve(dip, &ap);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out_end_trans;

	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
	if (error)
		goto out_brelse;

	gfs2_trans_add_meta(ip->i_gl, dibh);
	inc_nlink(&ip->i_inode);
	ip->i_inode.i_ctime = CURRENT_TIME;
	ihold(inode);
	d_instantiate(dentry, inode);
	mark_inode_dirty(inode);

out_brelse:
	brelse(dibh);
out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (da.nr_blocks)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (da.nr_blocks)
		gfs2_quota_unlock(dip);
out_gunlock:
	gfs2_dir_no_add(&da);
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	return error;
}

/*
 * gfs2_unlink_ok - check to see that a inode is still in a directory
 * @dip: the directory
 * @name: the name of the file
 * @ip: the inode
 *
 * Assumes that the lock on (at least) @dip is held.
 *
 * Returns: 0 if the parent/child relationship is correct, errno if it isn't
 */

static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
			  const struct gfs2_inode *ip)
{
	int error;

	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
		return -EPERM;

	if ((dip->i_inode.i_mode & S_ISVTX) &&
	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
		return -EPERM;

	if (IS_APPEND(&dip->i_inode))
		return -EPERM;

	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;

	error = gfs2_dir_check(&dip->i_inode, name, ip);
	if (error)
		return error;

	return 0;
}
示例#13
0
文件: file.c 项目: 7799/linux
static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = file_inode(vma->vm_file);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned long last_index;
	u64 pos = page->index << PAGE_CACHE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	struct gfs2_holder gh;
	loff_t size;
	int ret;

	sb_start_pagefault(inode->i_sb);

	/* Update file times before taking page lock */
	file_update_time(vma->vm_file);

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

	ret = gfs2_rs_alloc(ip);
	if (ret)
		goto out_write_access;

	gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out_uninit;

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) {
		lock_page(page);
		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
			ret = -EAGAIN;
			unlock_page(page);
		}
		goto out_unlock;
	}

	ret = gfs2_rindex_update(sdp);
	if (ret)
		goto out_unlock;

	ret = gfs2_quota_lock_check(ip);
	if (ret)
		goto out_unlock;
	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
	ap.target = data_blocks + ind_blocks;
	ret = gfs2_inplace_reserve(ip, &ap);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks) {
		rblocks += RES_STATFS + RES_QUOTA;
		rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
	}
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	size = i_size_read(inode);
	last_index = (size - 1) >> PAGE_CACHE_SHIFT;
	/* Check page index against inode size */
	if (size == 0 || (page->index > last_index))
		goto out_trans_end;

	ret = -EAGAIN;
	/* If truncated, we must retry the operation, we may have raced
	 * with the glock demotion code.
	 */
	if (!PageUptodate(page) || page->mapping != inode->i_mapping)
		goto out_trans_end;

	/* Unstuff, if required, and allocate backing blocks for page */
	ret = 0;
	if (gfs2_is_stuffed(ip))
		ret = gfs2_unstuff_dinode(ip, page);
	if (ret == 0)
		ret = gfs2_allocate_page_backing(page);

out_trans_end:
	if (ret)
		unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	if (ret == 0) {
		set_page_dirty(page);
		wait_for_stable_page(page);
	}
out_write_access:
	put_write_access(inode);
out:
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}

static const struct vm_operations_struct gfs2_vm_ops = {
	.fault = filemap_fault,
	.map_pages = filemap_map_pages,
	.page_mkwrite = gfs2_page_mkwrite,
	.remap_pages = generic_file_remap_pages,
};

/**
 * gfs2_mmap -
 * @file: The file to map
 * @vma: The VMA which described the mapping
 *
 * There is no need to get a lock here unless we should be updating
 * atime. We ignore any locking errors since the only consequence is
 * a missed atime update (which will just be deferred until later).
 *
 * Returns: 0
 */

static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);

	if (!(file->f_flags & O_NOATIME) &&
	    !IS_NOATIME(&ip->i_inode)) {
		struct gfs2_holder i_gh;
		int error;

		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		/* grab lock to update inode */
		gfs2_glock_dq_uninit(&i_gh);
		file_accessed(file);
	}
	vma->vm_ops = &gfs2_vm_ops;

	return 0;
}

/**
 * gfs2_open_common - This is common to open and atomic_open
 * @inode: The inode being opened
 * @file: The file being opened
 *
 * This maybe called under a glock or not depending upon how it has
 * been called. We must always be called under a glock for regular
 * files, however. For other file types, it does not matter whether
 * we hold the glock or not.
 *
 * Returns: Error code or 0 for success
 */

int gfs2_open_common(struct inode *inode, struct file *file)
{
	struct gfs2_file *fp;
	int ret;

	if (S_ISREG(inode->i_mode)) {
		ret = generic_file_open(inode, file);
		if (ret)
			return ret;
	}

	fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
	if (!fp)
		return -ENOMEM;

	mutex_init(&fp->f_fl_mutex);

	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
	file->private_data = fp;
	return 0;
}

/**
 * gfs2_open - open a file
 * @inode: the inode to open
 * @file: the struct file for this opening
 *
 * After atomic_open, this function is only used for opening files
 * which are already cached. We must still get the glock for regular
 * files to ensure that we have the file size uptodate for the large
 * file check which is in the common code. That is only an issue for
 * regular files though.
 *
 * Returns: errno
 */

static int gfs2_open(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder i_gh;
	int error;
	bool need_unlock = false;

	if (S_ISREG(ip->i_inode.i_mode)) {
		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		need_unlock = true;
	}

	error = gfs2_open_common(inode, file);

	if (need_unlock)
		gfs2_glock_dq_uninit(&i_gh);

	return error;
}

/**
 * gfs2_release - called to close a struct file
 * @inode: the inode the struct file belongs to
 * @file: the struct file being closed
 *
 * Returns: errno
 */

static int gfs2_release(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);

	kfree(file->private_data);
	file->private_data = NULL;

	if (!(file->f_mode & FMODE_WRITE))
		return 0;

	gfs2_rs_delete(ip, &inode->i_writecount);
	return 0;
}

/**
 * gfs2_fsync - sync the dirty data for a file (across the cluster)
 * @file: the file that points to the dentry
 * @start: the start position in the file to sync
 * @end: the end position in the file to sync
 * @datasync: set if we can ignore timestamp changes
 *
 * We split the data flushing here so that we don't wait for the data
 * until after we've also sent the metadata to disk. Note that for
 * data=ordered, we will write & wait for the data at the log flush
 * stage anyway, so this is unlikely to make much of a difference
 * except in the data=writeback case.
 *
 * If the fdatawrite fails due to any reason except -EIO, we will
 * continue the remainder of the fsync, although we'll still report
 * the error at the end. This is to match filemap_write_and_wait_range()
 * behaviour.
 *
 * Returns: errno
 */

static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
		      int datasync)
{
	struct address_space *mapping = file->f_mapping;
	struct inode *inode = mapping->host;
	int sync_state = inode->i_state & I_DIRTY;
	struct gfs2_inode *ip = GFS2_I(inode);
	int ret = 0, ret1 = 0;

	if (mapping->nrpages) {
		ret1 = filemap_fdatawrite_range(mapping, start, end);
		if (ret1 == -EIO)
			return ret1;
	}

	if (!gfs2_is_jdata(ip))
		sync_state &= ~I_DIRTY_PAGES;
	if (datasync)
		sync_state &= ~I_DIRTY_SYNC;

	if (sync_state) {
		ret = sync_inode_metadata(inode, 1);
		if (ret)
			return ret;
		if (gfs2_is_jdata(ip))
			filemap_write_and_wait(mapping);
		gfs2_ail_flush(ip->i_gl, 1);
	}

	if (mapping->nrpages)
		ret = filemap_fdatawait_range(mapping, start, end);

	return ret ? ret : ret1;
}

/**
 * gfs2_file_aio_write - Perform a write to a file
 * @iocb: The io context
 * @iov: The data to write
 * @nr_segs: Number of @iov segments
 * @pos: The file position
 *
 * We have to do a lock/unlock here to refresh the inode size for
 * O_APPEND writes, otherwise we can land up writing at the wrong
 * offset. There is still a race, but provided the app is using its
 * own file locking, this will make O_APPEND work as expected.
 *
 */

static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
				   unsigned long nr_segs, loff_t pos)
{
	struct file *file = iocb->ki_filp;
	size_t writesize = iov_length(iov, nr_segs);
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	int ret;

	ret = gfs2_rs_alloc(ip);
	if (ret)
		return ret;

	gfs2_size_hint(file, pos, writesize);

	if (file->f_flags & O_APPEND) {
		struct gfs2_holder gh;

		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
		if (ret)
			return ret;
		gfs2_glock_dq_uninit(&gh);
	}

	return generic_file_aio_write(iocb, iov, nr_segs, pos);
}

static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
			   int mode)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct buffer_head *dibh;
	int error;
	loff_t size = len;
	unsigned int nr_blks;
	sector_t lblock = offset >> inode->i_blkbits;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(error))
		return error;

	gfs2_trans_add_meta(ip->i_gl, dibh);

	if (gfs2_is_stuffed(ip)) {
		error = gfs2_unstuff_dinode(ip, NULL);
		if (unlikely(error))
			goto out;
	}

	while (len) {
		struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
		bh_map.b_size = len;
		set_buffer_zeronew(&bh_map);

		error = gfs2_block_map(inode, lblock, &bh_map, 1);
		if (unlikely(error))
			goto out;
		len -= bh_map.b_size;
		nr_blks = bh_map.b_size >> inode->i_blkbits;
		lblock += nr_blks;
		if (!buffer_new(&bh_map))
			continue;
		if (unlikely(!buffer_zeronew(&bh_map))) {
			error = -EIO;
			goto out;
		}
	}
	if (offset + size > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE))
		i_size_write(inode, offset + size);

	mark_inode_dirty(inode);

out:
	brelse(dibh);
	return error;
}

static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
			    unsigned int *data_blocks, unsigned int *ind_blocks)
{
	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	unsigned int max_blocks = ip->i_rgd->rd_free_clone;
	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);

	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
		max_data -= tmp;
	}
	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
	   so it might end up with fewer data blocks */
	if (max_data <= *data_blocks)
		return;
	*data_blocks = max_data;
	*ind_blocks = max_blocks - max_data;
	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
	if (*len > max) {
		*len = max;
		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
	}
}

static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
			   loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	loff_t bytes, max_bytes;
	int error;
	const loff_t pos = offset;
	const loff_t count = len;
	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
	loff_t max_chunk_size = UINT_MAX & bsize_mask;
	struct gfs2_holder gh;

	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;

	/* We only support the FALLOC_FL_KEEP_SIZE mode */
	if (mode & ~FALLOC_FL_KEEP_SIZE)
		return -EOPNOTSUPP;

	offset &= bsize_mask;

	len = next - offset;
	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
	if (!bytes)
		bytes = UINT_MAX;
	bytes &= bsize_mask;
	if (bytes == 0)
		bytes = sdp->sd_sb.sb_bsize;

	error = gfs2_rs_alloc(ip);
	if (error)
		return error;

	mutex_lock(&inode->i_mutex);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	error = gfs2_glock_nq(&gh);
	if (unlikely(error))
		goto out_uninit;

	gfs2_size_hint(file, offset, len);

	while (len > 0) {
		if (len < bytes)
			bytes = len;
		if (!gfs2_write_alloc_required(ip, offset, bytes)) {
			len -= bytes;
			offset += bytes;
			continue;
		}
		error = gfs2_quota_lock_check(ip);
		if (error)
			goto out_unlock;

retry:
		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);

		ap.target = data_blocks + ind_blocks;
		error = gfs2_inplace_reserve(ip, &ap);
		if (error) {
			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
				bytes >>= 1;
				bytes &= bsize_mask;
				if (bytes == 0)
					bytes = sdp->sd_sb.sb_bsize;
				goto retry;
			}
			goto out_qunlock;
		}
		max_bytes = bytes;
		calc_max_reserv(ip, (len > max_chunk_size)? max_chunk_size: len,
				&max_bytes, &data_blocks, &ind_blocks);

		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
			  RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
		if (gfs2_is_jdata(ip))
			rblocks += data_blocks ? data_blocks : 1;

		error = gfs2_trans_begin(sdp, rblocks,
					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
		if (error)
			goto out_trans_fail;

		error = fallocate_chunk(inode, offset, max_bytes, mode);
		gfs2_trans_end(sdp);

		if (error)
			goto out_trans_fail;

		len -= max_bytes;
		offset += max_bytes;
		gfs2_inplace_release(ip);
		gfs2_quota_unlock(ip);
	}

	if (error == 0)
		error = generic_write_sync(file, pos, count);
	goto out_unlock;

out_trans_fail:
	gfs2_inplace_release(ip);
out_qunlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	mutex_unlock(&inode->i_mutex);
	return error;
}

#ifdef CONFIG_GFS2_FS_LOCKING_DLM

/**
 * gfs2_setlease - acquire/release a file lease
 * @file: the file pointer
 * @arg: lease type
 * @fl: file lock
 *
 * We don't currently have a way to enforce a lease across the whole
 * cluster; until we do, disable leases (by just returning -EINVAL),
 * unless the administrator has requested purely local locking.
 *
 * Locking: called under i_lock
 *
 * Returns: errno
 */

static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
{
	return -EINVAL;
}

/**
 * gfs2_lock - acquire/release a posix lock on a file
 * @file: the file pointer
 * @cmd: either modify or retrieve lock state, possibly wait
 * @fl: type and range of lock
 *
 * Returns: errno
 */

static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;

	if (!(fl->fl_flags & FL_POSIX))
		return -ENOLCK;
	if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
		return -ENOLCK;

	if (cmd == F_CANCELLK) {
		/* Hack: */
		cmd = F_SETLK;
		fl->fl_type = F_UNLCK;
	}
	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
		if (fl->fl_type == F_UNLCK)
			posix_lock_file_wait(file, fl);
		return -EIO;
	}
	if (IS_GETLK(cmd))
		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
	else if (fl->fl_type == F_UNLCK)
		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
	else
		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
}

static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
	struct gfs2_file *fp = file->private_data;
	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	struct gfs2_glock *gl;
	unsigned int state;
	int flags;
	int error = 0;

	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;

	mutex_lock(&fp->f_fl_mutex);

	gl = fl_gh->gh_gl;
	if (gl) {
		if (fl_gh->gh_state == state)
			goto out;
		flock_lock_file_wait(file,
				     &(struct file_lock){.fl_type = F_UNLCK});
		gfs2_glock_dq_wait(fl_gh);
		gfs2_holder_reinit(state, flags, fl_gh);
	} else {
		error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
				       &gfs2_flock_glops, CREATE, &gl);
		if (error)
			goto out;
		gfs2_holder_init(gl, state, flags, fl_gh);
		gfs2_glock_put(gl);
	}
	error = gfs2_glock_nq(fl_gh);
	if (error) {
		gfs2_holder_uninit(fl_gh);
		if (error == GLR_TRYFAILED)
			error = -EAGAIN;
	} else {
		error = flock_lock_file_wait(file, fl);
		gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
	}

out:
	mutex_unlock(&fp->f_fl_mutex);
	return error;
}
示例#14
0
static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
		     struct dentry *dentry)
{
	struct gfs2_inode *dip = GFS2_I(dir);
	struct gfs2_sbd *sdp = GFS2_SB(dir);
	struct inode *inode = old_dentry->d_inode;
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder ghs[2];
	struct buffer_head *dibh;
	int alloc_required;
	int error;

	if (S_ISDIR(inode->i_mode))
		return -EPERM;

	error = gfs2_rs_alloc(dip);
	if (error)
		return error;

	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);

	error = gfs2_glock_nq(ghs); /* parent */
	if (error)
		goto out_parent;

	error = gfs2_glock_nq(ghs + 1); /* child */
	if (error)
		goto out_child;

	error = -ENOENT;
	if (inode->i_nlink == 0)
		goto out_gunlock;

	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		goto out_gunlock;

	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
	switch (error) {
	case -ENOENT:
		break;
	case 0:
		error = -EEXIST;
	default:
		goto out_gunlock;
	}

	error = -EINVAL;
	if (!dip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EFBIG;
	if (dip->i_entries == (u32)-1)
		goto out_gunlock;
	error = -EPERM;
	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
		goto out_gunlock;
	error = -EINVAL;
	if (!ip->i_inode.i_nlink)
		goto out_gunlock;
	error = -EMLINK;
	if (ip->i_inode.i_nlink == (u32)-1)
		goto out_gunlock;

	alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
	if (error < 0)
		goto out_gunlock;
	error = 0;

	if (alloc_required) {
		error = gfs2_quota_lock_check(dip);
		if (error)
			goto out_gunlock;

		error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres, 0);
		if (error)
			goto out_gunlock_q;

		error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
					 gfs2_rg_blocks(dip, sdp->sd_max_dirres) +
					 2 * RES_DINODE + RES_STATFS +
					 RES_QUOTA, 0);
		if (error)
			goto out_ipres;
	} else {
		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
		if (error)
			goto out_ipres;
	}

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		goto out_end_trans;

	error = gfs2_dir_add(dir, &dentry->d_name, ip);
	if (error)
		goto out_brelse;

	gfs2_trans_add_meta(ip->i_gl, dibh);
	inc_nlink(&ip->i_inode);
	ip->i_inode.i_ctime = CURRENT_TIME;
	ihold(inode);
	d_instantiate(dentry, inode);
	mark_inode_dirty(inode);

out_brelse:
	brelse(dibh);
out_end_trans:
	gfs2_trans_end(sdp);
out_ipres:
	if (alloc_required)
		gfs2_inplace_release(dip);
out_gunlock_q:
	if (alloc_required)
		gfs2_quota_unlock(dip);
out_gunlock:
	gfs2_glock_dq(ghs + 1);
out_child:
	gfs2_glock_dq(ghs);
out_parent:
	gfs2_holder_uninit(ghs);
	gfs2_holder_uninit(ghs + 1);
	return error;
}
示例#15
0
static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
			const char *symname, struct buffer_head **bhp)
{
	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
	struct gfs2_dinode *di;
	struct buffer_head *dibh;
	struct timespec tv = CURRENT_TIME;

	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
	gfs2_trans_add_meta(ip->i_gl, dibh);
	gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
	di = (struct gfs2_dinode *)dibh->b_data;

	di->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
	di->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
	di->di_mode = cpu_to_be32(ip->i_inode.i_mode);
	di->di_uid = cpu_to_be32(ip->i_inode.i_uid);
	di->di_gid = cpu_to_be32(ip->i_inode.i_gid);
	di->di_nlink = 0;
	di->di_size = cpu_to_be64(ip->i_inode.i_size);
	di->di_blocks = cpu_to_be64(1);
	di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(tv.tv_sec);
	di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
	di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
	di->di_goal_meta = di->di_goal_data = cpu_to_be64(ip->i_no_addr);
	di->di_generation = cpu_to_be64(ip->i_generation);
	di->di_flags = 0;
	di->__pad1 = 0;
	di->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) ? GFS2_FORMAT_DE : 0);
	di->di_height = 0;
	di->__pad2 = 0;
	di->__pad3 = 0;
	di->di_depth = 0;
	di->di_entries = 0;
	memset(&di->__pad4, 0, sizeof(di->__pad4));
	di->di_eattr = 0;
	di->di_atime_nsec = cpu_to_be32(tv.tv_nsec);
	di->di_mtime_nsec = cpu_to_be32(tv.tv_nsec);
	di->di_ctime_nsec = cpu_to_be32(tv.tv_nsec);
	memset(&di->di_reserved, 0, sizeof(di->di_reserved));

	switch(ip->i_inode.i_mode & S_IFMT) {
	case S_IFREG:
		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
		    gfs2_tune_get(sdp, gt_new_files_jdata))
			di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
		break;
	case S_IFDIR:
		di->di_flags |= cpu_to_be32(dip->i_diskflags &
					    GFS2_DIF_INHERIT_JDATA);
		di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
		di->di_size = cpu_to_be64(sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode));
		di->di_entries = cpu_to_be32(2);
		gfs2_init_dir(dibh, dip);
		break;
	case S_IFLNK:
		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
		break;
	}

	set_buffer_uptodate(dibh);

	*bhp = dibh;
}
示例#16
0
static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
			   int mode)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct buffer_head *dibh;
	int error;
	loff_t size = len;
	unsigned int nr_blks;
	sector_t lblock = offset >> inode->i_blkbits;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(error))
		return error;

	gfs2_trans_add_meta(ip->i_gl, dibh);

	if (gfs2_is_stuffed(ip)) {
		error = gfs2_unstuff_dinode(ip, NULL);
		if (unlikely(error))
			goto out;
	}

	while (len) {
		struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
		bh_map.b_size = len;
		set_buffer_zeronew(&bh_map);

		error = gfs2_block_map(inode, lblock, &bh_map, 1);
		if (unlikely(error))
			goto out;
		len -= bh_map.b_size;
		nr_blks = bh_map.b_size >> inode->i_blkbits;
		lblock += nr_blks;
		if (!buffer_new(&bh_map))
			continue;
		if (unlikely(!buffer_zeronew(&bh_map))) {
			error = -EIO;
			goto out;
		}
	}
	if (offset + size > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE))
		i_size_write(inode, offset + size);

	mark_inode_dirty(inode);

out:
	brelse(dibh);
	return error;
}

static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
			    unsigned int *data_blocks, unsigned int *ind_blocks)
{
	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	unsigned int max_blocks = ip->i_rgd->rd_free_clone;
	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);

	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
		max_data -= tmp;
	}
	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
	   so it might end up with fewer data blocks */
	if (max_data <= *data_blocks)
		return;
	*data_blocks = max_data;
	*ind_blocks = max_blocks - max_data;
	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
	if (*len > max) {
		*len = max;
		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
	}
}

static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
			   loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	loff_t bytes, max_bytes;
	int error;
	const loff_t pos = offset;
	const loff_t count = len;
	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
	loff_t max_chunk_size = UINT_MAX & bsize_mask;
	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;

	/* We only support the FALLOC_FL_KEEP_SIZE mode */
	if (mode & ~FALLOC_FL_KEEP_SIZE)
		return -EOPNOTSUPP;

	offset &= bsize_mask;

	len = next - offset;
	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
	if (!bytes)
		bytes = UINT_MAX;
	bytes &= bsize_mask;
	if (bytes == 0)
		bytes = sdp->sd_sb.sb_bsize;

	error = gfs2_rs_alloc(ip);
	if (error)
		return error;

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
	error = gfs2_glock_nq(&ip->i_gh);
	if (unlikely(error))
		goto out_uninit;

	gfs2_size_hint(file, offset, len);

	while (len > 0) {
		if (len < bytes)
			bytes = len;
		if (!gfs2_write_alloc_required(ip, offset, bytes)) {
			len -= bytes;
			offset += bytes;
			continue;
		}
		error = gfs2_quota_lock_check(ip);
		if (error)
			goto out_unlock;

retry:
		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);

		error = gfs2_inplace_reserve(ip, data_blocks + ind_blocks, 0);
		if (error) {
			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
				bytes >>= 1;
				bytes &= bsize_mask;
				if (bytes == 0)
					bytes = sdp->sd_sb.sb_bsize;
				goto retry;
			}
			goto out_qunlock;
		}
		max_bytes = bytes;
		calc_max_reserv(ip, (len > max_chunk_size)? max_chunk_size: len,
				&max_bytes, &data_blocks, &ind_blocks);

		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
			  RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
		if (gfs2_is_jdata(ip))
			rblocks += data_blocks ? data_blocks : 1;

		error = gfs2_trans_begin(sdp, rblocks,
					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
		if (error)
			goto out_trans_fail;

		error = fallocate_chunk(inode, offset, max_bytes, mode);
		gfs2_trans_end(sdp);

		if (error)
			goto out_trans_fail;

		len -= max_bytes;
		offset += max_bytes;
		gfs2_inplace_release(ip);
		gfs2_quota_unlock(ip);
	}

	if (error == 0)
		error = generic_write_sync(file, pos, count);
	goto out_unlock;

out_trans_fail:
	gfs2_inplace_release(ip);
out_qunlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&ip->i_gh);
out_uninit:
	gfs2_holder_uninit(&ip->i_gh);
	return error;
}
示例#17
0
文件: bmap.c 项目: 383530895/linux
static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
			   struct buffer_head *bh_map, struct metapath *mp,
			   const unsigned int sheight,
			   const unsigned int height,
			   const size_t maxlen)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct super_block *sb = sdp->sd_vfs;
	struct buffer_head *dibh = mp->mp_bh[0];
	u64 bn, dblock = 0;
	unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
	unsigned dblks = 0;
	unsigned ptrs_per_blk;
	const unsigned end_of_metadata = height - 1;
	int ret;
	int eob = 0;
	enum alloc_state state;
	__be64 *ptr;
	__be64 zero_bn = 0;

	BUG_ON(sheight < 1);
	BUG_ON(dibh == NULL);

	gfs2_trans_add_meta(ip->i_gl, dibh);

	if (height == sheight) {
		struct buffer_head *bh;
		/* Bottom indirect block exists, find unalloced extent size */
		ptr = metapointer(end_of_metadata, mp);
		bh = mp->mp_bh[end_of_metadata];
		dblks = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen,
					   &eob);
		BUG_ON(dblks < 1);
		state = ALLOC_DATA;
	} else {
		/* Need to allocate indirect blocks */
		ptrs_per_blk = height > 1 ? sdp->sd_inptrs : sdp->sd_diptrs;
		dblks = min(maxlen, (size_t)(ptrs_per_blk -
					     mp->mp_list[end_of_metadata]));
		if (height == ip->i_height) {
			/* Writing into existing tree, extend tree down */
			iblks = height - sheight;
			state = ALLOC_GROW_DEPTH;
		} else {
			/* Building up tree height */
			state = ALLOC_GROW_HEIGHT;
			iblks = height - ip->i_height;
			branch_start = metapath_branch_start(mp);
			iblks += (height - branch_start);
		}
	}

	/* start of the second part of the function (state machine) */

	blks = dblks + iblks;
	i = sheight;
	do {
		int error;
		n = blks - alloced;
		error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL);
		if (error)
			return error;
		alloced += n;
		if (state != ALLOC_DATA || gfs2_is_jdata(ip))
			gfs2_trans_add_unrevoke(sdp, bn, n);
		switch (state) {
		/* Growing height of tree */
		case ALLOC_GROW_HEIGHT:
			if (i == 1) {
				ptr = (__be64 *)(dibh->b_data +
						 sizeof(struct gfs2_dinode));
				zero_bn = *ptr;
			}
			for (; i - 1 < height - ip->i_height && n > 0; i++, n--)
				gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++);
			if (i - 1 == height - ip->i_height) {
				i--;
				gfs2_buffer_copy_tail(mp->mp_bh[i],
						sizeof(struct gfs2_meta_header),
						dibh, sizeof(struct gfs2_dinode));
				gfs2_buffer_clear_tail(dibh,
						sizeof(struct gfs2_dinode) +
						sizeof(__be64));
				ptr = (__be64 *)(mp->mp_bh[i]->b_data +
					sizeof(struct gfs2_meta_header));
				*ptr = zero_bn;
				state = ALLOC_GROW_DEPTH;
				for(i = branch_start; i < height; i++) {
					if (mp->mp_bh[i] == NULL)
						break;
					brelse(mp->mp_bh[i]);
					mp->mp_bh[i] = NULL;
				}
				i = branch_start;
			}
			if (n == 0)
				break;
		/* Branching from existing tree */
		case ALLOC_GROW_DEPTH:
			if (i > 1 && i < height)
				gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[i-1]);
			for (; i < height && n > 0; i++, n--)
				gfs2_indirect_init(mp, ip->i_gl, i,
						   mp->mp_list[i-1], bn++);
			if (i == height)
				state = ALLOC_DATA;
			if (n == 0)
				break;
		/* Tree complete, adding data blocks */
		case ALLOC_DATA:
			BUG_ON(n > dblks);
			BUG_ON(mp->mp_bh[end_of_metadata] == NULL);
			gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[end_of_metadata]);
			dblks = n;
			ptr = metapointer(end_of_metadata, mp);
			dblock = bn;
			while (n-- > 0)
				*ptr++ = cpu_to_be64(bn++);
			if (buffer_zeronew(bh_map)) {
				ret = sb_issue_zeroout(sb, dblock, dblks,
						       GFP_NOFS);
				if (ret) {
					fs_err(sdp,
					       "Failed to zero data buffers\n");
					clear_buffer_zeronew(bh_map);
				}
			}
			break;
		}
	} while ((state != ALLOC_DATA) || !dblock);

	ip->i_height = height;
	gfs2_add_inode_blocks(&ip->i_inode, alloced);
	gfs2_dinode_out(ip, mp->mp_bh[0]->b_data);
	map_bh(bh_map, inode->i_sb, dblock);
	bh_map->b_size = dblks << inode->i_blkbits;
	set_buffer_new(bh_map);
	return 0;
}