fs.h (21733B)
- /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
- #ifndef _LINUX_FS_H
- #define _LINUX_FS_H
- /*
- * This file has definitions for some important file table structures
- * and constants and structures used by various generic file system
- * ioctl's. Please do not make any changes in this file before
- * sending patches for review to linux-fsdevel@vger.kernel.org and
- * linux-api@vger.kernel.org.
- */
- #include <linux/limits.h>
- #include <linux/ioctl.h>
- #include <linux/types.h>
- #include <linux/fscrypt.h>
- /* Use of MS_* flags within the kernel is restricted to core mount(2) code. */
- #include <linux/mount.h>
- /*
- * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
- * the file limit at runtime and only root can increase the per-process
- * nr_file rlimit, so it's safe to set up a ridiculously high absolute
- * upper limit on files-per-process.
- *
- * Some programs (notably those using select()) may have to be
- * recompiled to take full advantage of the new limits..
- */
- /* Fixed constants first: */
- #undef NR_OPEN
- #define INR_OPEN_CUR 1024 /* Initial setting for nfile rlimits */
- #define INR_OPEN_MAX 4096 /* Hard limit for nfile rlimits */
- #define BLOCK_SIZE_BITS 10
- #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
- #define SEEK_SET 0 /* seek relative to beginning of file */
- #define SEEK_CUR 1 /* seek relative to current file position */
- #define SEEK_END 2 /* seek relative to end of file */
- #define SEEK_DATA 3 /* seek to the next data */
- #define SEEK_HOLE 4 /* seek to the next hole */
- #define SEEK_MAX SEEK_HOLE
- #define RENAME_NOREPLACE (1 << 0) /* Don't overwrite target */
- #define RENAME_EXCHANGE (1 << 1) /* Exchange source and dest */
- #define RENAME_WHITEOUT (1 << 2) /* Whiteout source */
- struct file_clone_range {
- __s64 src_fd;
- __u64 src_offset;
- __u64 src_length;
- __u64 dest_offset;
- };
- struct fstrim_range {
- __u64 start;
- __u64 len;
- __u64 minlen;
- };
- /*
- * We include a length field because some filesystems (vfat) have an identifier
- * that we do want to expose as a UUID, but doesn't have the standard length.
- *
- * We use a fixed size buffer beacuse this interface will, by fiat, never
- * support "UUIDs" longer than 16 bytes; we don't want to force all downstream
- * users to have to deal with that.
- */
- struct fsuuid2 {
- __u8 len;
- __u8 uuid[16];
- };
- struct fs_sysfs_path {
- __u8 len;
- __u8 name[128];
- };
- /* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */
- #define FILE_DEDUPE_RANGE_SAME 0
- #define FILE_DEDUPE_RANGE_DIFFERS 1
- /* from struct btrfs_ioctl_file_extent_same_info */
- struct file_dedupe_range_info {
- __s64 dest_fd; /* in - destination file */
- __u64 dest_offset; /* in - start of extent in destination */
- __u64 bytes_deduped; /* out - total # of bytes we were able
- * to dedupe from this file. */
- /* status of this dedupe operation:
- * < 0 for error
- * == FILE_DEDUPE_RANGE_SAME if dedupe succeeds
- * == FILE_DEDUPE_RANGE_DIFFERS if data differs
- */
- __s32 status; /* out - see above description */
- __u32 reserved; /* must be zero */
- };
- /* from struct btrfs_ioctl_file_extent_same_args */
- struct file_dedupe_range {
- __u64 src_offset; /* in - start of extent in source */
- __u64 src_length; /* in - length of extent */
- __u16 dest_count; /* in - total elements in info array */
- __u16 reserved1; /* must be zero */
- __u32 reserved2; /* must be zero */
- struct file_dedupe_range_info info[];
- };
- /* And dynamically-tunable limits and defaults: */
- struct files_stat_struct {
- unsigned long nr_files; /* read only */
- unsigned long nr_free_files; /* read only */
- unsigned long max_files; /* tunable */
- };
- struct inodes_stat_t {
- long nr_inodes;
- long nr_unused;
- long dummy[5]; /* padding for sysctl ABI compatibility */
- };
- #define NR_FILE 8192 /* this can well be larger on a larger system */
- /*
- * Structure for FS_IOC_FSGETXATTR[A] and FS_IOC_FSSETXATTR.
- */
- struct fsxattr {
- __u32 fsx_xflags; /* xflags field value (get/set) */
- __u32 fsx_extsize; /* extsize field value (get/set)*/
- __u32 fsx_nextents; /* nextents field value (get) */
- __u32 fsx_projid; /* project identifier (get/set) */
- __u32 fsx_cowextsize; /* CoW extsize field value (get/set)*/
- unsigned char fsx_pad[8];
- };
- /*
- * Flags for the fsx_xflags field
- */
- #define FS_XFLAG_REALTIME 0x00000001 /* data in realtime volume */
- #define FS_XFLAG_PREALLOC 0x00000002 /* preallocated file extents */
- #define FS_XFLAG_IMMUTABLE 0x00000008 /* file cannot be modified */
- #define FS_XFLAG_APPEND 0x00000010 /* all writes append */
- #define FS_XFLAG_SYNC 0x00000020 /* all writes synchronous */
- #define FS_XFLAG_NOATIME 0x00000040 /* do not update access time */
- #define FS_XFLAG_NODUMP 0x00000080 /* do not include in backups */
- #define FS_XFLAG_RTINHERIT 0x00000100 /* create with rt bit set */
- #define FS_XFLAG_PROJINHERIT 0x00000200 /* create with parents projid */
- #define FS_XFLAG_NOSYMLINKS 0x00000400 /* disallow symlink creation */
- #define FS_XFLAG_EXTSIZE 0x00000800 /* extent size allocator hint */
- #define FS_XFLAG_EXTSZINHERIT 0x00001000 /* inherit inode extent size */
- #define FS_XFLAG_NODEFRAG 0x00002000 /* do not defragment */
- #define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
- #define FS_XFLAG_DAX 0x00008000 /* use DAX for IO */
- #define FS_XFLAG_COWEXTSIZE 0x00010000 /* CoW extent size allocator hint */
- #define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */
- /* the read-only stuff doesn't really belong here, but any other place is
- probably as bad and I don't want to create yet another include file. */
- #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
- #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
- #define BLKRRPART _IO(0x12,95) /* re-read partition table */
- #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
- #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
- #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
- #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
- #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
- #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
- #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
- #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
- #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
- #if 0
- #define BLKPG _IO(0x12,105)/* See blkpg.h */
- /* Some people are morons. Do not use sizeof! */
- #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
- #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
- /* This was here just to show that the number is taken -
- probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
- #endif
- /* A jump here: 108-111 have been used for various private purposes. */
- #define BLKBSZGET _IOR(0x12,112,size_t)
- #define BLKBSZSET _IOW(0x12,113,size_t)
- #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
- #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
- #define BLKTRACESTART _IO(0x12,116)
- #define BLKTRACESTOP _IO(0x12,117)
- #define BLKTRACETEARDOWN _IO(0x12,118)
- #define BLKDISCARD _IO(0x12,119)
- #define BLKIOMIN _IO(0x12,120)
- #define BLKIOOPT _IO(0x12,121)
- #define BLKALIGNOFF _IO(0x12,122)
- #define BLKPBSZGET _IO(0x12,123)
- #define BLKDISCARDZEROES _IO(0x12,124)
- #define BLKSECDISCARD _IO(0x12,125)
- #define BLKROTATIONAL _IO(0x12,126)
- #define BLKZEROOUT _IO(0x12,127)
- #define BLKGETDISKSEQ _IOR(0x12,128,__u64)
- /*
- * A jump here: 130-136 are reserved for zoned block devices
- * (see uapi/linux/blkzoned.h)
- */
- #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
- #define FIBMAP _IO(0x00,1) /* bmap access */
- #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
- #define FIFREEZE _IOWR('X', 119, int) /* Freeze */
- #define FITHAW _IOWR('X', 120, int) /* Thaw */
- #define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */
- #define FICLONE _IOW(0x94, 9, int)
- #define FICLONERANGE _IOW(0x94, 13, struct file_clone_range)
- #define FIDEDUPERANGE _IOWR(0x94, 54, struct file_dedupe_range)
- #define FSLABEL_MAX 256 /* Max chars for the interface; each fs may differ */
- #define FS_IOC_GETFLAGS _IOR('f', 1, long)
- #define FS_IOC_SETFLAGS _IOW('f', 2, long)
- #define FS_IOC_GETVERSION _IOR('v', 1, long)
- #define FS_IOC_SETVERSION _IOW('v', 2, long)
- #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap)
- #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
- #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
- #define FS_IOC32_GETVERSION _IOR('v', 1, int)
- #define FS_IOC32_SETVERSION _IOW('v', 2, int)
- #define FS_IOC_FSGETXATTR _IOR('X', 31, struct fsxattr)
- #define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
- #define FS_IOC_GETFSLABEL _IOR(0x94, 49, char[FSLABEL_MAX])
- #define FS_IOC_SETFSLABEL _IOW(0x94, 50, char[FSLABEL_MAX])
- /* Returns the external filesystem UUID, the same one blkid returns */
- #define FS_IOC_GETFSUUID _IOR(0x15, 0, struct fsuuid2)
- /*
- * Returns the path component under /sys/fs/ that refers to this filesystem;
- * also /sys/kernel/debug/ for filesystems with debugfs exports
- */
- #define FS_IOC_GETFSSYSFSPATH _IOR(0x15, 1, struct fs_sysfs_path)
- /*
- * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
- *
- * Note: for historical reasons, these flags were originally used and
- * defined for use by ext2/ext3, and then other file systems started
- * using these flags so they wouldn't need to write their own version
- * of chattr/lsattr (which was shipped as part of e2fsprogs). You
- * should think twice before trying to use these flags in new
- * contexts, or trying to assign these flags, since they are used both
- * as the UAPI and the on-disk encoding for ext2/3/4. Also, we are
- * almost out of 32-bit flags. :-)
- *
- * We have recently hoisted FS_IOC_FSGETXATTR / FS_IOC_FSSETXATTR from
- * XFS to the generic FS level interface. This uses a structure that
- * has padding and hence has more room to grow, so it may be more
- * appropriate for many new use cases.
- *
- * Please do not change these flags or interfaces before checking with
- * linux-fsdevel@vger.kernel.org and linux-api@vger.kernel.org.
- */
- #define FS_SECRM_FL 0x00000001 /* Secure deletion */
- #define FS_UNRM_FL 0x00000002 /* Undelete */
- #define FS_COMPR_FL 0x00000004 /* Compress file */
- #define FS_SYNC_FL 0x00000008 /* Synchronous updates */
- #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
- #define FS_APPEND_FL 0x00000020 /* writes to file may only append */
- #define FS_NODUMP_FL 0x00000040 /* do not dump file */
- #define FS_NOATIME_FL 0x00000080 /* do not update atime */
- /* Reserved for compression usage... */
- #define FS_DIRTY_FL 0x00000100
- #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
- #define FS_NOCOMP_FL 0x00000400 /* Don't compress */
- /* End compression flags --- maybe not all used */
- #define FS_ENCRYPT_FL 0x00000800 /* Encrypted file */
- #define FS_BTREE_FL 0x00001000 /* btree format dir */
- #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
- #define FS_IMAGIC_FL 0x00002000 /* AFS directory */
- #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
- #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
- #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
- #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
- #define FS_HUGE_FILE_FL 0x00040000 /* Reserved for ext4 */
- #define FS_EXTENT_FL 0x00080000 /* Extents */
- #define FS_VERITY_FL 0x00100000 /* Verity protected inode */
- #define FS_EA_INODE_FL 0x00200000 /* Inode used for large EA */
- #define FS_EOFBLOCKS_FL 0x00400000 /* Reserved for ext4 */
- #define FS_NOCOW_FL 0x00800000 /* Do not cow file */
- #define FS_DAX_FL 0x02000000 /* Inode is DAX */
- #define FS_INLINE_DATA_FL 0x10000000 /* Reserved for ext4 */
- #define FS_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
- #define FS_CASEFOLD_FL 0x40000000 /* Folder is case insensitive */
- #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
- #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
- #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
- #define SYNC_FILE_RANGE_WAIT_BEFORE 1
- #define SYNC_FILE_RANGE_WRITE 2
- #define SYNC_FILE_RANGE_WAIT_AFTER 4
- #define SYNC_FILE_RANGE_WRITE_AND_WAIT (SYNC_FILE_RANGE_WRITE | \
- SYNC_FILE_RANGE_WAIT_BEFORE | \
- SYNC_FILE_RANGE_WAIT_AFTER)
- /*
- * Flags for preadv2/pwritev2:
- */
- typedef int __bitwise __kernel_rwf_t;
- /* high priority request, poll if possible */
- #define RWF_HIPRI ((__kernel_rwf_t)0x00000001)
- /* per-IO O_DSYNC */
- #define RWF_DSYNC ((__kernel_rwf_t)0x00000002)
- /* per-IO O_SYNC */
- #define RWF_SYNC ((__kernel_rwf_t)0x00000004)
- /* per-IO, return -EAGAIN if operation would block */
- #define RWF_NOWAIT ((__kernel_rwf_t)0x00000008)
- /* per-IO O_APPEND */
- #define RWF_APPEND ((__kernel_rwf_t)0x00000010)
- /* per-IO negation of O_APPEND */
- #define RWF_NOAPPEND ((__kernel_rwf_t)0x00000020)
- /* Atomic Write */
- #define RWF_ATOMIC ((__kernel_rwf_t)0x00000040)
- /* mask of flags supported by the kernel */
- #define RWF_SUPPORTED (RWF_HIPRI | RWF_DSYNC | RWF_SYNC | RWF_NOWAIT |\
- RWF_APPEND | RWF_NOAPPEND | RWF_ATOMIC)
- #define PROCFS_IOCTL_MAGIC 'f'
- /* Pagemap ioctl */
- #define PAGEMAP_SCAN _IOWR(PROCFS_IOCTL_MAGIC, 16, struct pm_scan_arg)
- /* Bitmasks provided in pm_scan_args masks and reported in page_region.categories. */
- #define PAGE_IS_WPALLOWED (1 << 0)
- #define PAGE_IS_WRITTEN (1 << 1)
- #define PAGE_IS_FILE (1 << 2)
- #define PAGE_IS_PRESENT (1 << 3)
- #define PAGE_IS_SWAPPED (1 << 4)
- #define PAGE_IS_PFNZERO (1 << 5)
- #define PAGE_IS_HUGE (1 << 6)
- #define PAGE_IS_SOFT_DIRTY (1 << 7)
- /*
- * struct page_region - Page region with flags
- * @start: Start of the region
- * @end: End of the region (exclusive)
- * @categories: PAGE_IS_* category bitmask for the region
- */
- struct page_region {
- __u64 start;
- __u64 end;
- __u64 categories;
- };
- /* Flags for PAGEMAP_SCAN ioctl */
- #define PM_SCAN_WP_MATCHING (1 << 0) /* Write protect the pages matched. */
- #define PM_SCAN_CHECK_WPASYNC (1 << 1) /* Abort the scan when a non-WP-enabled page is found. */
- /*
- * struct pm_scan_arg - Pagemap ioctl argument
- * @size: Size of the structure
- * @flags: Flags for the IOCTL
- * @start: Starting address of the region
- * @end: Ending address of the region
- * @walk_end Address where the scan stopped (written by kernel).
- * walk_end == end (address tags cleared) informs that the scan completed on entire range.
- * @vec: Address of page_region struct array for output
- * @vec_len: Length of the page_region struct array
- * @max_pages: Optional limit for number of returned pages (0 = disabled)
- * @category_inverted: PAGE_IS_* categories which values match if 0 instead of 1
- * @category_mask: Skip pages for which any category doesn't match
- * @category_anyof_mask: Skip pages for which no category matches
- * @return_mask: PAGE_IS_* categories that are to be reported in `page_region`s returned
- */
- struct pm_scan_arg {
- __u64 size;
- __u64 flags;
- __u64 start;
- __u64 end;
- __u64 walk_end;
- __u64 vec;
- __u64 vec_len;
- __u64 max_pages;
- __u64 category_inverted;
- __u64 category_mask;
- __u64 category_anyof_mask;
- __u64 return_mask;
- };
- /* /proc/<pid>/maps ioctl */
- #define PROCMAP_QUERY _IOWR(PROCFS_IOCTL_MAGIC, 17, struct procmap_query)
- enum procmap_query_flags {
- /*
- * VMA permission flags.
- *
- * Can be used as part of procmap_query.query_flags field to look up
- * only VMAs satisfying specified subset of permissions. E.g., specifying
- * PROCMAP_QUERY_VMA_READABLE only will return both readable and read/write VMAs,
- * while having PROCMAP_QUERY_VMA_READABLE | PROCMAP_QUERY_VMA_WRITABLE will only
- * return read/write VMAs, though both executable/non-executable and
- * private/shared will be ignored.
- *
- * PROCMAP_QUERY_VMA_* flags are also returned in procmap_query.vma_flags
- * field to specify actual VMA permissions.
- */
- PROCMAP_QUERY_VMA_READABLE = 0x01,
- PROCMAP_QUERY_VMA_WRITABLE = 0x02,
- PROCMAP_QUERY_VMA_EXECUTABLE = 0x04,
- PROCMAP_QUERY_VMA_SHARED = 0x08,
- /*
- * Query modifier flags.
- *
- * By default VMA that covers provided address is returned, or -ENOENT
- * is returned. With PROCMAP_QUERY_COVERING_OR_NEXT_VMA flag set, closest
- * VMA with vma_start > addr will be returned if no covering VMA is
- * found.
- *
- * PROCMAP_QUERY_FILE_BACKED_VMA instructs query to consider only VMAs that
- * have file backing. Can be combined with PROCMAP_QUERY_COVERING_OR_NEXT_VMA
- * to iterate all VMAs with file backing.
- */
- PROCMAP_QUERY_COVERING_OR_NEXT_VMA = 0x10,
- PROCMAP_QUERY_FILE_BACKED_VMA = 0x20,
- };
- /*
- * Input/output argument structured passed into ioctl() call. It can be used
- * to query a set of VMAs (Virtual Memory Areas) of a process.
- *
- * Each field can be one of three kinds, marked in a short comment to the
- * right of the field:
- * - "in", input argument, user has to provide this value, kernel doesn't modify it;
- * - "out", output argument, kernel sets this field with VMA data;
- * - "in/out", input and output argument; user provides initial value (used
- * to specify maximum allowable buffer size), and kernel sets it to actual
- * amount of data written (or zero, if there is no data).
- *
- * If matching VMA is found (according to criterias specified by
- * query_addr/query_flags, all the out fields are filled out, and ioctl()
- * returns 0. If there is no matching VMA, -ENOENT will be returned.
- * In case of any other error, negative error code other than -ENOENT is
- * returned.
- *
- * Most of the data is similar to the one returned as text in /proc/<pid>/maps
- * file, but procmap_query provides more querying flexibility. There are no
- * consistency guarantees between subsequent ioctl() calls, but data returned
- * for matched VMA is self-consistent.
- */
- struct procmap_query {
- /* Query struct size, for backwards/forward compatibility */
- __u64 size;
- /*
- * Query flags, a combination of enum procmap_query_flags values.
- * Defines query filtering and behavior, see enum procmap_query_flags.
- *
- * Input argument, provided by user. Kernel doesn't modify it.
- */
- __u64 query_flags; /* in */
- /*
- * Query address. By default, VMA that covers this address will
- * be looked up. PROCMAP_QUERY_* flags above modify this default
- * behavior further.
- *
- * Input argument, provided by user. Kernel doesn't modify it.
- */
- __u64 query_addr; /* in */
- /* VMA starting (inclusive) and ending (exclusive) address, if VMA is found. */
- __u64 vma_start; /* out */
- __u64 vma_end; /* out */
- /* VMA permissions flags. A combination of PROCMAP_QUERY_VMA_* flags. */
- __u64 vma_flags; /* out */
- /* VMA backing page size granularity. */
- __u64 vma_page_size; /* out */
- /*
- * VMA file offset. If VMA has file backing, this specifies offset
- * within the file that VMA's start address corresponds to.
- * Is set to zero if VMA has no backing file.
- */
- __u64 vma_offset; /* out */
- /* Backing file's inode number, or zero, if VMA has no backing file. */
- __u64 inode; /* out */
- /* Backing file's device major/minor number, or zero, if VMA has no backing file. */
- __u32 dev_major; /* out */
- __u32 dev_minor; /* out */
- /*
- * If set to non-zero value, signals the request to return VMA name
- * (i.e., VMA's backing file's absolute path, with " (deleted)" suffix
- * appended, if file was unlinked from FS) for matched VMA. VMA name
- * can also be some special name (e.g., "[heap]", "[stack]") or could
- * be even user-supplied with prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME).
- *
- * Kernel will set this field to zero, if VMA has no associated name.
- * Otherwise kernel will return actual amount of bytes filled in
- * user-supplied buffer (see vma_name_addr field below), including the
- * terminating zero.
- *
- * If VMA name is longer that user-supplied maximum buffer size,
- * -E2BIG error is returned.
- *
- * If this field is set to non-zero value, vma_name_addr should point
- * to valid user space memory buffer of at least vma_name_size bytes.
- * If set to zero, vma_name_addr should be set to zero as well
- */
- __u32 vma_name_size; /* in/out */
- /*
- * If set to non-zero value, signals the request to extract and return
- * VMA's backing file's build ID, if the backing file is an ELF file
- * and it contains embedded build ID.
- *
- * Kernel will set this field to zero, if VMA has no backing file,
- * backing file is not an ELF file, or ELF file has no build ID
- * embedded.
- *
- * Build ID is a binary value (not a string). Kernel will set
- * build_id_size field to exact number of bytes used for build ID.
- * If build ID is requested and present, but needs more bytes than
- * user-supplied maximum buffer size (see build_id_addr field below),
- * -E2BIG error will be returned.
- *
- * If this field is set to non-zero value, build_id_addr should point
- * to valid user space memory buffer of at least build_id_size bytes.
- * If set to zero, build_id_addr should be set to zero as well
- */
- __u32 build_id_size; /* in/out */
- /*
- * User-supplied address of a buffer of at least vma_name_size bytes
- * for kernel to fill with matched VMA's name (see vma_name_size field
- * description above for details).
- *
- * Should be set to zero if VMA name should not be returned.
- */
- __u64 vma_name_addr; /* in */
- /*
- * User-supplied address of a buffer of at least build_id_size bytes
- * for kernel to fill with matched VMA's ELF build ID, if available
- * (see build_id_size field description above for details).
- *
- * Should be set to zero if build ID should not be returned.
- */
- __u64 build_id_addr; /* in */
- };
- #endif /* _LINUX_FS_H */