path: root/fs/ceph/xattr.c

#include <linux/ceph/ceph_debug.h>

#include "super.h"
#include "mds_client.h"

#include <linux/ceph/decode.h>

#include <linux/xattr.h>
#include <linux/slab.h>

#define XATTR_CEPH_PREFIX "ceph."
#define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)

static bool ceph_is_valid_xattr(const char *name)
{
	return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
	       !strncmp(name, XATTR_SECURITY_PREFIX,
			XATTR_SECURITY_PREFIX_LEN) ||
	       !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
	       !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
}

/*
 * These define virtual xattrs exposing the recursive directory
 * statistics and layout metadata.
 */
struct ceph_vxattr {
	char *name;
	size_t name_size;	/* strlen(name) + 1 (for '\0') */
	size_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
			      size_t size);
	bool readonly, hidden;
	bool (*exists_cb)(struct ceph_inode_info *ci);
};

/* directories */

static size_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
					size_t size)
{
	return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs);
}

static size_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
				      size_t size)
{
	return snprintf(val, size, "%lld", ci->i_files);
}

static size_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
					size_t size)
{
	return snprintf(val, size, "%lld", ci->i_subdirs);
}

static size_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
					 size_t size)
{
	return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs);
}

static size_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
				       size_t size)
{
	return snprintf(val, size, "%lld", ci->i_rfiles);
}

static size_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
					 size_t size)
{
	return snprintf(val, size, "%lld", ci->i_rsubdirs);
}

static size_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
				       size_t size)
{
	return snprintf(val, size, "%lld", ci->i_rbytes);
}

static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
				       size_t size)
{
	return snprintf(val, size, "%ld.09%ld", (long)ci->i_rctime.tv_sec,
			(long)ci->i_rctime.tv_nsec);
}

#define CEPH_XATTR_NAME(_type, _name)	XATTR_CEPH_PREFIX #_type "." #_name

#define XATTR_NAME_CEPH(_type, _name)					\
	{								\
		.name = CEPH_XATTR_NAME(_type, _name),			\
		.name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
		.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
		.readonly = true,				\
		.hidden = false,				\
		.exists_cb = NULL,			\
	}

static struct ceph_vxattr ceph_dir_vxattrs[] = {
	XATTR_NAME_CEPH(dir, entries),
	XATTR_NAME_CEPH(dir, files),
	XATTR_NAME_CEPH(dir, subdirs),
	XATTR_NAME_CEPH(dir, rentries),
	XATTR_NAME_CEPH(dir, rfiles),
	XATTR_NAME_CEPH(dir, rsubdirs),
	XATTR_NAME_CEPH(dir, rbytes),
	XATTR_NAME_CEPH(dir, rctime),
	{ 0 }	/* Required table terminator */
};
static size_t ceph_dir_vxattrs_name_size;	/* total size of all names */

/* files */

static size_t ceph_vxattrcb_file_layout(struct ceph_inode_info *ci, char *val,
				   size_t size)
{
	int ret;

	ret = snprintf(val, size,
		"chunk_bytes=%lld\nstripe_count=%lld\nobject_size=%lld\n",
		(unsigned long long)ceph_file_layout_su(ci->i_layout),
		(unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
		(unsigned long long)ceph_file_layout_object_size(ci->i_layout));
	return ret;
}

static struct ceph_vxattr ceph_file_vxattrs[] = {
	XATTR_NAME_CEPH(file, layout),
	{ 0 }	/* Required table terminator */
};
static size_t ceph_file_vxattrs_name_size;	/* total size of all names */

static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
{
	if (S_ISDIR(inode->i_mode))
		return ceph_dir_vxattrs;
	else if (S_ISREG(inode->i_mode))
		return ceph_file_vxattrs;
	return NULL;
}

static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs)
{
	if (vxattrs == ceph_dir_vxattrs)
		return ceph_dir_vxattrs_name_size;
	if (vxattrs == ceph_file_vxattrs)
		return ceph_file_vxattrs_name_size;
	BUG();

	return 0;
}

/*
 * Compute the aggregate size (including terminating '\0') of all
 * virtual extended attribute names in the given vxattr table.
 */