file.c

ocfs1.4.1 oracle分布式文件系统

out_update_size:
	ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
	if (ret < 0)
		mlog_errno(ret);

out:
	return ret;
}

int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
{
	int status = 0, size_change;
	struct inode *inode = dentry->d_inode;
	struct super_block *sb = inode->i_sb;
	struct ocfs2_super *osb = OCFS2_SB(sb);
	struct buffer_head *bh = NULL;
	handle_t *handle = NULL;

	mlog_entry("(0x%p, '%.*s')\n", dentry,
	           dentry->d_name.len, dentry->d_name.name);

	/* ensuring we don't even attempt to truncate a symlink */
	if (S_ISLNK(inode->i_mode))
		attr->ia_valid &= ~ATTR_SIZE;

	if (attr->ia_valid & ATTR_MODE)
		mlog(0, "mode change: %d\n", attr->ia_mode);
	if (attr->ia_valid & ATTR_UID)
		mlog(0, "uid change: %d\n", attr->ia_uid);
	if (attr->ia_valid & ATTR_GID)
		mlog(0, "gid change: %d\n", attr->ia_gid);
	if (attr->ia_valid & ATTR_SIZE)
		mlog(0, "size change...\n");
	if (attr->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME))
		mlog(0, "time change...\n");

#define OCFS2_VALID_ATTRS (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME | ATTR_SIZE \
			   | ATTR_GID | ATTR_UID | ATTR_MODE)
	if (!(attr->ia_valid & OCFS2_VALID_ATTRS)) {
		mlog(0, "can't handle attrs: 0x%x\n", attr->ia_valid);
		return 0;
	}

	status = inode_change_ok(inode, attr);
	if (status)
		return status;

	size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
	if (size_change) {
		status = ocfs2_rw_lock(inode, 1);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}
	}

	status = ocfs2_inode_lock(inode, &bh, 1);
	if (status < 0) {
		if (status != -ENOENT)
			mlog_errno(status);
		goto bail_unlock_rw;
	}

	if (size_change && attr->ia_size != i_size_read(inode)) {
		if (attr->ia_size > sb->s_maxbytes) {
			status = -EFBIG;
			goto bail_unlock;
		}

		if (i_size_read(inode) > attr->ia_size)
			status = ocfs2_truncate_file(inode, bh, attr->ia_size);
		else
			status = ocfs2_extend_file(inode, bh, attr->ia_size);
		if (status < 0) {
			if (status != -ENOSPC)
				mlog_errno(status);
			status = -ENOSPC;
			goto bail_unlock;
		}
	}

	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
	if (IS_ERR(handle)) {
		status = PTR_ERR(handle);
		mlog_errno(status);
		goto bail_unlock;
	}

	/*
	 * This will intentionally not wind up calling vmtruncate(),
	 * since all the work for a size change has been done above.
	 * Otherwise, we could get into problems with truncate as
	 * ip_alloc_sem is used there to protect against i_size
	 * changes.
	 */
	status = inode_setattr(inode, attr);
	if (status < 0) {
		mlog_errno(status);
		goto bail_commit;
	}

	status = ocfs2_mark_inode_dirty(handle, inode, bh);
	if (status < 0)
		mlog_errno(status);

bail_commit:
	ocfs2_commit_trans(osb, handle);
bail_unlock:
	ocfs2_inode_unlock(inode, 1);
bail_unlock_rw:
	if (size_change)
		ocfs2_rw_unlock(inode, 1);
bail:
	if (bh)
		brelse(bh);

	mlog_exit(status);
	return status;
}

int ocfs2_getattr(struct vfsmount *mnt,
		  struct dentry *dentry,
		  struct kstat *stat)
{
	struct inode *inode = dentry->d_inode;
	struct super_block *sb = dentry->d_inode->i_sb;
	struct ocfs2_super *osb = sb->s_fs_info;
	int err;

	mlog_entry_void();

	err = ocfs2_inode_revalidate(dentry);
	if (err) {
		if (err != -ENOENT)
			mlog_errno(err);
		goto bail;
	}

	generic_fillattr(inode, stat);

	/* We set the blksize from the cluster size for performance */
	stat->blksize = osb->s_clustersize;

bail:
	mlog_exit(err);

	return err;
}

int ocfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
{
	int ret;

	mlog_entry_void();

	ret = ocfs2_inode_lock(inode, NULL, 0);
	if (ret) {
		if (ret != -ENOENT)
			mlog_errno(ret);
		goto out;
	}

	ret = generic_permission(inode, mask, NULL);

	ocfs2_inode_unlock(inode, 0);
out:
	mlog_exit(ret);
	return ret;
}

static int __ocfs2_write_remove_suid(struct inode *inode,
				     struct buffer_head *bh)
{
	int ret;
	handle_t *handle;
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	struct ocfs2_dinode *di;

	mlog_entry("(Inode %llu, mode 0%o)\n",
		   (unsigned long long)OCFS2_I(inode)->ip_blkno, inode->i_mode);

	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
	if (handle == NULL) {
		ret = -ENOMEM;
		mlog_errno(ret);
		goto out;
	}

	ret = ocfs2_journal_access(handle, inode, bh,
				   OCFS2_JOURNAL_ACCESS_WRITE);
	if (ret < 0) {
		mlog_errno(ret);
		goto out_trans;
	}

	inode->i_mode &= ~S_ISUID;
	if ((inode->i_mode & S_ISGID) && (inode->i_mode & S_IXGRP))
		inode->i_mode &= ~S_ISGID;

	di = (struct ocfs2_dinode *) bh->b_data;
	di->i_mode = cpu_to_le16(inode->i_mode);

	ret = ocfs2_journal_dirty(handle, bh);
	if (ret < 0)
		mlog_errno(ret);

out_trans:
	ocfs2_commit_trans(osb, handle);
out:
	mlog_exit(ret);
	return ret;
}

/*
 * Will look for holes and unwritten extents in the range starting at
 * pos for count bytes (inclusive).
 */
static int ocfs2_check_range_for_holes(struct inode *inode, loff_t pos,
				       size_t count)
{
	int ret = 0;
	unsigned int extent_flags;
	u32 cpos, clusters, extent_len, phys_cpos;
	struct super_block *sb = inode->i_sb;

	cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
	clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;

	while (clusters) {
		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
					 &extent_flags);
		if (ret < 0) {
			mlog_errno(ret);
			goto out;
		}

		if (phys_cpos == 0 || (extent_flags & OCFS2_EXT_UNWRITTEN)) {
			ret = 1;
			break;
		}

		if (extent_len > clusters)
			extent_len = clusters;

		clusters -= extent_len;
		cpos += extent_len;
	}
out:
	return ret;
}

static int ocfs2_write_remove_suid(struct inode *inode)
{
	int ret;
	struct buffer_head *bh = NULL;
	struct ocfs2_inode_info *oi = OCFS2_I(inode);

	ret = ocfs2_read_block(OCFS2_SB(inode->i_sb),
			       oi->ip_blkno, &bh, OCFS2_BH_CACHED, inode);
	if (ret < 0) {
		mlog_errno(ret);
		goto out;
	}

	ret =  __ocfs2_write_remove_suid(inode, bh);
out:
	brelse(bh);
	return ret;
}

/*
 * Allocate enough extents to cover the region starting at byte offset
 * start for len bytes. Existing extents are skipped, any extents
 * added are marked as "unwritten".
 */
static int ocfs2_allocate_unwritten_extents(struct inode *inode,
					    u64 start, u64 len)
{
	int ret;
	u32 cpos, phys_cpos, clusters, alloc_size;
	u64 end = start + len;
	struct buffer_head *di_bh = NULL;

	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
		ret = ocfs2_read_block(OCFS2_SB(inode->i_sb),
				       OCFS2_I(inode)->ip_blkno, &di_bh,
				       OCFS2_BH_CACHED, inode);
		if (ret) {
			mlog_errno(ret);
			goto out;
		}

		/*
		 * Nothing to do if the requested reservation range
		 * fits within the inode.
		 */
		if (ocfs2_size_fits_inline_data(di_bh, end))
			goto out;

		ret = ocfs2_convert_inline_data_to_extents(inode, di_bh);
		if (ret) {
			mlog_errno(ret);
			goto out;
		}
	}

	/*
	 * We consider both start and len to be inclusive.
	 */
	cpos = start >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
	clusters = ocfs2_clusters_for_bytes(inode->i_sb, start + len);
	clusters -= cpos;

	while (clusters) {
		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos,
					 &alloc_size, NULL);
		if (ret) {
			mlog_errno(ret);
			goto out;
		}

		/*
		 * Hole or existing extent len can be arbitrary, so
		 * cap it to our own allocation request.
		 */
		if (alloc_size > clusters)
			alloc_size = clusters;

		if (phys_cpos) {
			/*
			 * We already have an allocation at this
			 * region so we can safely skip it.
			 */
			goto next;
		}

		ret = __ocfs2_extend_allocation(inode, cpos, alloc_size, 1);
		if (ret) {
			if (ret != -ENOSPC)
				mlog_errno(ret);
			goto out;
		}

next:
		cpos += alloc_size;
		clusters -= alloc_size;
	}

	ret = 0;
out:

	brelse(di_bh);
	return ret;
}

static int __ocfs2_remove_inode_range(struct inode *inode,
				      struct buffer_head *di_bh,
				      u32 cpos, u32 phys_cpos, u32 len,
				      struct ocfs2_cached_dealloc_ctxt *dealloc)
{
	int ret;
	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	struct inode *tl_inode = osb->osb_tl_inode;
	handle_t *handle;
	struct ocfs2_alloc_context *meta_ac = NULL;
	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;

	ret = ocfs2_lock_allocators(inode, di, 0, 1, NULL, &meta_ac);
	if (ret) {
		mlog_errno(ret);
		return ret;
	}

	mutex_lock(&tl_inode->i_mutex);

	if (ocfs2_truncate_log_needs_flush(osb)) {
		ret = __ocfs2_flush_truncate_log(osb);
		if (ret < 0) {
			mlog_errno(ret);
			goto out;
		}
	}

	handle = ocfs2_start_trans(osb, OCFS2_REMOVE_EXTENT_CREDITS);
	if (handle == NULL) {
		ret = -ENOMEM;
		mlog_errno(ret);
		goto out;
	}

	ret = ocfs2_journal_access(handle, inode, di_bh,
				   OCFS2_JOURNAL_ACCESS_WRITE);
	if (ret) {
		mlog_errno(ret);
		goto out;
	}

	ret = ocfs2_remove_extent(inode, di_bh, cpos, len, handle, meta_ac,
				  dealloc);
	if (ret) {
		mlog_errno(ret);
		goto out_commit;
	}

	OCFS2_I(inode)->ip_clusters -= len;
	di->i_clusters = cpu_to_le32(OCFS2_I(inode)->ip_clusters);

	ret = ocfs2_journal_dirty(handle, di_bh);
	if (ret) {
		mlog_errno(ret);
		goto out_commit;
	}

	ret = ocfs2_truncate_log_append(osb, handle, phys_blkno, len);
	if (ret)
		mlog_errno(ret);

out_commit:
	ocfs2_commit_trans(osb, handle);
out:
	mutex_unlock(&tl_inode->i_mutex);

	if (meta_ac)
		ocfs2_free_alloc_context(meta_ac);

	return ret;
}

/*
 * Truncate a byte range, avoiding pages within partial clusters. This
 * preserves those pages for the zeroing code to write to.
 */
static void ocfs2_truncate_cluster_pages(struct inode *inode, u64 byte_start,
					 u64 byte_len)
{
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	loff_t start, end;
	struct address_space *mapping = inode->i_mapping;

	start = (loff_t)ocfs2_align_bytes_to_clusters(inode->i_sb, byte_start);
	end = byte_start + byte_len;
	end = end & ~(osb->s_clustersize - 1);

	if (start < end) {
		unmap_mapping_range(mapping, start, end - start, 0);
		truncate_inode_pages_range(mapping, start, end - 1);
	}
}

static int ocfs2_zero_partial_clusters(struct inode *inode,
				       u64 start, u64 len)
{
	int ret = 0;
	u64 tmpend, end = start + len;
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	unsigned int csize = osb->s_clustersize;
	handle_t *handle;

	/*
	 * The "start" and "end" values are NOT necessarily part of
	 * the range whose allocation is being deleted. Rather, this
	 * is what the user passed in with the request. We must zero
	 * partial clusters here. There's no need to worry about
	 * physical allocation - the zeroing code knows to skip holes.
	 */
	mlog(0, "byte start: %llu, end: %llu\n",
	     (unsigned long long)start, (unsigned long long)end);

	/*
	 * If both edges are on a cluster boundary then there's no
	 * zeroing required as the region is part of the allocation to
	 * be truncated.
	 */
	if ((start & (csize - 1)) == 0 && (end & (csize - 1)) == 0)
		goto out;

	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
	if (handle == NULL) {
		ret = -ENOMEM;
		mlog_errno(ret);
		goto out;
	}

	/*
	 * We want to get the byte offset of the end of the 1st cluster.
	 */
	tmpend = (u64)osb->s_clustersize + (start & ~(osb->s_clustersize - 1));
	if (tmpend > end)
		tmpend = end;

	mlog(0, "1st range: start: %llu, tmpend: %llu\n",
	     (unsigned long long)start, (unsigned long long)tmpend);

	ret = ocfs2_zero_range_for_truncate(inode, handle, start, tmpend);
	if (ret)
		mlog_errno(ret);

	if (tmpend < end) {
		/*
		 * This may make start and end equal, but the zeroing
		 * code will skip any work in that case so there's no
		 * need to catch it up here.
		 */
		start = end & ~(osb->s_clustersize - 1);

		mlog(0, "2nd range: start: %llu, end: %llu\n",
		     (unsigned long long)start, (unsigned long long)end);

		ret = ocfs2_zero_range_for_truncate(inode, handle, start, end);
		if (ret)
			mlog_errno(ret);
	}

	ocfs2_commit_trans(osb, handle);
out: