linux-stable/include/uapi/linux/fsmap.h

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License cleanup: add SPDX license identifier to uapi header files with no license Many user space API headers are missing licensing information, which makes it hard for compliance tools to determine the correct license. By default are files without license information under the default license of the kernel, which is GPLV2. Marking them GPLV2 would exclude them from being included in non GPLV2 code, which is obviously not intended. The user space API headers fall under the syscall exception which is in the kernels COPYING file: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". otherwise syscall usage would not be possible. Update the files which contain no license information with an SPDX license identifier. The chosen identifier is 'GPL-2.0 WITH Linux-syscall-note' which is the officially assigned identifier for the Linux syscall exception. SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:08:43 +00:00
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* FS_IOC_GETFSMAP ioctl infrastructure.
*
* Copyright (C) 2017 Oracle. All Rights Reserved.
*
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#ifndef _LINUX_FSMAP_H
#define _LINUX_FSMAP_H
#include <linux/types.h>
/*
* Structure for FS_IOC_GETFSMAP.
*
* The memory layout for this call are the scalar values defined in
* struct fsmap_head, followed by two struct fsmap that describe
* the lower and upper bound of mappings to return, followed by an
* array of struct fsmap mappings.
*
* fmh_iflags control the output of the call, whereas fmh_oflags report
* on the overall record output. fmh_count should be set to the
* length of the fmh_recs array, and fmh_entries will be set to the
* number of entries filled out during each call. If fmh_count is
* zero, the number of reverse mappings will be returned in
* fmh_entries, though no mappings will be returned. fmh_reserved
* must be set to zero.
*
* The two elements in the fmh_keys array are used to constrain the
* output. The first element in the array should represent the
* lowest disk mapping ("low key") that the user wants to learn
* about. If this value is all zeroes, the filesystem will return
* the first entry it knows about. For a subsequent call, the
* contents of fsmap_head.fmh_recs[fsmap_head.fmh_count - 1] should be
* copied into fmh_keys[0] to have the kernel start where it left off.
*
* The second element in the fmh_keys array should represent the
* highest disk mapping ("high key") that the user wants to learn
* about. If this value is all ones, the filesystem will not stop
* until it runs out of mapping to return or runs out of space in
* fmh_recs.
*
* fmr_device can be either a 32-bit cookie representing a device, or
* a 32-bit dev_t if the FMH_OF_DEV_T flag is set. fmr_physical,
* fmr_offset, and fmr_length are expressed in units of bytes.
* fmr_owner is either an inode number, or a special value if
* FMR_OF_SPECIAL_OWNER is set in fmr_flags.
*/
struct fsmap {
__u32 fmr_device; /* device id */
__u32 fmr_flags; /* mapping flags */
__u64 fmr_physical; /* device offset of segment */
__u64 fmr_owner; /* owner id */
__u64 fmr_offset; /* file offset of segment */
__u64 fmr_length; /* length of segment */
__u64 fmr_reserved[3]; /* must be zero */
};
struct fsmap_head {
__u32 fmh_iflags; /* control flags */
__u32 fmh_oflags; /* output flags */
__u32 fmh_count; /* # of entries in array incl. input */
__u32 fmh_entries; /* # of entries filled in (output). */
__u64 fmh_reserved[6]; /* must be zero */
struct fsmap fmh_keys[2]; /* low and high keys for the mapping search */
struct fsmap fmh_recs[]; /* returned records */
};
/* Size of an fsmap_head with room for nr records. */
static inline size_t
fsmap_sizeof(
unsigned int nr)
{
return sizeof(struct fsmap_head) + nr * sizeof(struct fsmap);
}
/* Start the next fsmap query at the end of the current query results. */
static inline void
fsmap_advance(
struct fsmap_head *head)
{
head->fmh_keys[0] = head->fmh_recs[head->fmh_entries - 1];
}
/* fmh_iflags values - set by FS_IOC_GETFSMAP caller in the header. */
/* no flags defined yet */
#define FMH_IF_VALID 0
/* fmh_oflags values - returned in the header segment only. */
#define FMH_OF_DEV_T 0x1 /* fmr_device values will be dev_t */
/* fmr_flags values - returned for each non-header segment */
#define FMR_OF_PREALLOC 0x1 /* segment = unwritten pre-allocation */
#define FMR_OF_ATTR_FORK 0x2 /* segment = attribute fork */
#define FMR_OF_EXTENT_MAP 0x4 /* segment = extent map */
#define FMR_OF_SHARED 0x8 /* segment = shared with another file */
#define FMR_OF_SPECIAL_OWNER 0x10 /* owner is a special value */
#define FMR_OF_LAST 0x20 /* segment is the last in the dataset */
/* Each FS gets to define its own special owner codes. */
#define FMR_OWNER(type, code) (((__u64)type << 32) | \
((__u64)code & 0xFFFFFFFFULL))
#define FMR_OWNER_TYPE(owner) ((__u32)((__u64)owner >> 32))
#define FMR_OWNER_CODE(owner) ((__u32)(((__u64)owner & 0xFFFFFFFFULL)))
#define FMR_OWN_FREE FMR_OWNER(0, 1) /* free space */
#define FMR_OWN_UNKNOWN FMR_OWNER(0, 2) /* unknown owner */
#define FMR_OWN_METADATA FMR_OWNER(0, 3) /* metadata */
#define FS_IOC_GETFSMAP _IOWR('X', 59, struct fsmap_head)
#endif /* _LINUX_FSMAP_H */