[PATCH RFC 2/2] xfs_io: hook up statx

[Eric Sandeen <sandeen@redhat.com>]

Wire up the statx syscall to xfs_io.

xfs_io> help statx
statx [-O | -m mask][-FDLAP] -- extended information about the currently open file

 Display extended file status.

 Options:
 -m mask -- Specify the field mask for the statx call (default STATX_ALL)
 -A -- Suppress terminal automount traversal
 -D -- Don't sync attributes with the server
 -F -- Force the attributes to be sync'd with the server
 -L -- Follow symlinks (statx link target)
 -O -- Remove basic stats (STATX_BASIC_STATS) from default mask
 -P -- pretty-print results similar to stat(1)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

diff --git a/io/init.c b/io/init.c
index 06002e6..c15a1e1 100644
--- a/io/init.c
+++ b/io/init.c
@@ -86,6 +86,7 @@ init_commands(void)
 	seek_init();
 	sendfile_init();
 	shutdown_init();
+	stat_init();
 	sync_init();
 	sync_range_init();
 	truncate_init();
diff --git a/io/io.h b/io/io.h
index 7e95bd5..952bdb8 100644
--- a/io/io.h
+++ b/io/io.h
@@ -112,6 +112,7 @@ extern void		pwrite_init(void);
 extern void		quit_init(void);
 extern void		seek_init(void);
 extern void		shutdown_init(void);
+extern void		stat_init(void);
 extern void		sync_init(void);
 extern void		truncate_init(void);
 extern void		utimes_init(void);
diff --git a/io/stat.c b/io/stat.c
index 3ae9903..3b3d21d 100644
--- a/io/stat.c
+++ b/io/stat.c
@@ -2,6 +2,9 @@
  * Copyright (c) 2003-2005 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
+ * Copyright (C) 2015, 2017 Red Hat, Inc.
+ * Portions of statx support written by David Howells (dhowells@redhat.com)
+ *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation.
@@ -20,10 +23,14 @@
 #include "input.h"
 #include "init.h"
 #include "io.h"
+#include "statx.h"
 #include "libxfs.h"
 
+#include <fcntl.h>
+
 static cmdinfo_t stat_cmd;
 static cmdinfo_t statfs_cmd;
+static cmdinfo_t statx_cmd;
 
 off64_t
 filesize(void)
@@ -167,6 +174,289 @@ statfs_f(
 	return 0;
 }
 
+#ifndef AT_STATX_SYNC_TYPE
+#define AT_STATX_SYNC_TYPE      0x6000  /* Type of synchronisation required from statx() */
+#define AT_STATX_SYNC_AS_STAT   0x0000  /* - Do whatever stat() does */
+#define AT_STATX_FORCE_SYNC     0x2000  /* - Force the attributes to be sync'd with the server */
+#define AT_STATX_DONT_SYNC      0x4000  /* - Don't sync attributes with the server */
+#endif
+
+#ifndef AT_NO_AUTOMOUNT
+#define AT_NO_AUTOMOUNT		0x800	/* Suppress terminal automount traversal */
+#endif
+
+/* XXX ERS fixme */
+#define __NR_statx 332
+
+static ssize_t
+statx(int dfd, const char *filename, unsigned flags,
+      unsigned int mask, struct statx *buffer)
+{
+	return syscall(__NR_statx, dfd, filename, flags, mask, buffer);
+}
+
+static void
+statx_help(void)
+{
+        printf(_(
+"\n"
+" Display extended file status.\n"
+"\n"
+" Options:\n"
+" -m mask -- Specify the field mask for the statx call (default STATX_ALL)\n"
+" -A -- Suppress terminal automount traversal\n"
+" -D -- Don't sync attributes with the server\n"
+" -F -- Force the attributes to be sync'd with the server\n"
+" -L -- Follow symlinks (statx link target)\n"
+" -O -- Remove basic stats (STATX_BASIC_STATS) from default mask\n"
+" -P -- pretty-print results similar to stat(1)\n"
+"\n"));
+}
+
+/* statx helper */
+static void
+raw_statx(struct statx *stx)
+{
+	printf("stx_mask: 0x%x\n", stx->stx_mask);
+	printf("stx_blksize: %u\n", stx->stx_blksize);
+	printf("stx_attributes: 0x%llx\n", stx->stx_attributes);
+	printf("stx_nlink: %u\n", stx->stx_nlink);
+	printf("stx_uid: %u\n", stx->stx_uid);
+	printf("stx_gid: %u\n", stx->stx_gid);
+	printf("stx_mode: 0%o\n", stx->stx_mode);
+	printf("stx_ino: %llu\n", stx->stx_ino);
+	printf("stx_size: %llu\n", stx->stx_size);
+	printf("stx_blocks: %llu\n", stx->stx_blocks);
+	printf("stx_atime.tv_sec: %lld\n", stx->stx_atime.tv_sec);
+	printf("stx_atime.tv_nsec: %d\n", stx->stx_atime.tv_nsec);
+	printf("stx_btime.tv_sec: %lld\n", stx->stx_btime.tv_sec);
+	printf("stx_btime.tv_nsec: %d\n", stx->stx_btime.tv_nsec);
+	printf("stx_ctime.tv_sec: %lld\n", stx->stx_ctime.tv_sec);
+	printf("stx_ctime.tv_nsec: %d\n", stx->stx_ctime.tv_nsec);
+	printf("stx_mtime.tv_sec: %lld\n", stx->stx_mtime.tv_sec);
+	printf("stx_mtime.tv_nsec: %d\n", stx->stx_mtime.tv_nsec);
+	printf("stx_rdev_major: %u\n", stx->stx_rdev_major);
+	printf("stx_rdev_minor: %u\n", stx->stx_rdev_minor);
+	printf("stx_dev_major: %u\n", stx->stx_dev_major);
+	printf("stx_dev_minor: %u\n", stx->stx_dev_minor);
+}
+
+/* statx helper */
+static void
+print_time(const char *field, struct statx_timestamp *ts)
+{
+	struct tm tm;
+	time_t tim;
+	char buffer[100];
+	int len;
+
+	tim = ts->tv_sec;
+	if (!localtime_r(&tim, &tm)) {
+		perror("localtime_r");
+		exit(1);
+	}
+	len = strftime(buffer, 100, "%F %T", &tm);
+	if (len == 0) {
+		perror("strftime");
+		exit(1);
+	}
+	printf("%s", field);
+	fwrite(buffer, 1, len, stdout);
+	printf(".%09u", ts->tv_nsec);
+	len = strftime(buffer, 100, "%z", &tm);
+	if (len == 0) {
+		perror("strftime2");
+		exit(1);
+	}
+	fwrite(buffer, 1, len, stdout);
+	printf("\n");
+}
+
+/* statx helper */
+static void
+pretty_statx(struct statx *stx)
+{
+	char buffer[256], ft;
+
+	printf(" ");
+	if (stx->stx_mask & STATX_SIZE)
+		printf(" Size: %-15llu", (unsigned long long)stx->stx_size);
+	if (stx->stx_mask & STATX_BLOCKS)
+		printf(" Blocks: %-10llu", (unsigned long long)stx->stx_blocks);
+	printf(" IO Block: %-6llu", (unsigned long long)stx->stx_blksize);
+
+	ft = '?';
+	if (stx->stx_mask & STATX_TYPE) {
+		switch (stx->stx_mode & S_IFMT) {
+		case S_IFIFO:	printf("  FIFO\n");			ft = 'p'; break;
+		case S_IFCHR:	printf("  character special file\n");	ft = 'c'; break;
+		case S_IFDIR:	printf("  directory\n");		ft = 'd'; break;
+		case S_IFBLK:	printf("  block special file\n");	ft = 'b'; break;
+		case S_IFREG:	printf("  regular file\n");		ft = '-'; break;
+		case S_IFLNK:	printf("  symbolic link\n");		ft = 'l'; break;
+		case S_IFSOCK:	printf("  socket\n");			ft = 's'; break;
+		default:
+			printf(" unknown type (%o)\n", stx->stx_mode & S_IFMT);
+			break;
+		}
+	} else {
+		printf(" no type\n");
+	}
+
+	sprintf(buffer, "%02x:%02x", stx->stx_dev_major, stx->stx_dev_minor);
+	printf("Device: %-15s", buffer);
+	if (stx->stx_mask & STATX_INO)
+		printf(" Inode: %-11llu", (unsigned long long) stx->stx_ino);
+	if (stx->stx_mask & STATX_NLINK)
+		printf(" Links: %-5u", stx->stx_nlink);
+	if (stx->stx_mask & STATX_TYPE) {
+		switch (stx->stx_mode & S_IFMT) {
+		case S_IFBLK:
+		case S_IFCHR:
+			printf(" Device type: %u,%u",
+			       stx->stx_rdev_major, stx->stx_rdev_minor);
+			break;
+		}
+	}
+	printf("\n");
+
+	if (stx->stx_mask & STATX_MODE)
+		printf("Access: (%04o/%c%c%c%c%c%c%c%c%c%c)  ",
+		       stx->stx_mode & 07777,
+		       ft,
+		       stx->stx_mode & S_IRUSR ? 'r' : '-',
+		       stx->stx_mode & S_IWUSR ? 'w' : '-',
+		       stx->stx_mode & S_IXUSR ? 'x' : '-',
+		       stx->stx_mode & S_IRGRP ? 'r' : '-',
+		       stx->stx_mode & S_IWGRP ? 'w' : '-',
+		       stx->stx_mode & S_IXGRP ? 'x' : '-',
+		       stx->stx_mode & S_IROTH ? 'r' : '-',
+		       stx->stx_mode & S_IWOTH ? 'w' : '-',
+		       stx->stx_mode & S_IXOTH ? 'x' : '-');
+	if (stx->stx_mask & STATX_UID)
+		printf("Uid: %5d   ", stx->stx_uid);
+	if (stx->stx_mask & STATX_GID)
+		printf("Gid: %5d\n", stx->stx_gid);
+
+	if (stx->stx_mask & STATX_ATIME)
+		print_time("Access: ", &stx->stx_atime);
+	if (stx->stx_mask & STATX_MTIME)
+		print_time("Modify: ", &stx->stx_mtime);
+	if (stx->stx_mask & STATX_CTIME)
+		print_time("Change: ", &stx->stx_ctime);
+	if (stx->stx_mask & STATX_BTIME)
+		print_time(" Birth: ", &stx->stx_btime);
+
+	if (stx->stx_attributes) {
+		unsigned char bits;
+		int loop, byte;
+
+		static char attr_representation[64 + 1] =
+			/* STATX_ATTR_ flags: */
+			"????????"	/* 63-56 */
+			"????????"	/* 55-48 */
+			"????????"	/* 47-40 */
+			"????????"	/* 39-32 */
+			"????????"	/* 31-24	0x00000000-ff000000 */
+			"????????"	/* 23-16	0x00000000-00ff0000 */
+			"???mE???"	/* 15- 8	0x00000000-0000ff00 */
+			"?dai?c??"	/*  7- 0	0x00000000-000000ff */
+			;
+
+		printf("Attributes: %016llx\n", stx->stx_attributes);
+		printf("(");
+		for (byte = 64 - 8; byte >= 0; byte -= 8) {
+			bits = stx->stx_attributes >> byte;
+			for (loop = 7; loop >= 0; loop--) {
+				int bit = byte + loop;
+
+				if (bits & 0x80)
+					putchar(attr_representation[63 - bit]);
+				else
+					putchar('-');
+				bits <<= 1;
+			}
+			if (byte)
+				putchar(' ');
+		}
+		printf(")\n");
+	}
+}
+
+/*
+ * options:
+ * 	- input flags - query type
+ * 	- output style for flags (and all else?) (chars vs. hex?)
+ * 	- output - mask out incidental flag or not?
+ */
+int
+statx_f(
+	int		argc,
+	char		**argv)
+{
+	int		c;
+	int		pretty = 0;
+	struct statx	stx;
+	int		atflag = AT_SYMLINK_NOFOLLOW;
+	unsigned int	m_mask = 0;	/* mask requested with -m */
+	int		Oflag = 0, mflag = 0;	/* -O or -m was used */
+	unsigned int	 mask = STATX_ALL;
+
+	while ((c = getopt(argc, argv, "m:FDLOAP")) != EOF) {
+		switch (c) {
+		case 'm':
+			m_mask = atoi(optarg);
+			mflag = 1;
+			break;
+		case 'F':
+			atflag &= ~AT_STATX_SYNC_TYPE;
+			atflag |= AT_STATX_FORCE_SYNC;
+			break;
+		case 'D':
+			atflag &= ~AT_STATX_SYNC_TYPE;
+			atflag |= AT_STATX_DONT_SYNC;
+			break;
+		case 'L':
+			atflag &= ~AT_SYMLINK_NOFOLLOW;
+			break;
+		case 'O':
+			mask &= ~STATX_BASIC_STATS;
+			Oflag = 1;
+			break;
+		case 'A':
+			atflag |= AT_NO_AUTOMOUNT;
+			break;
+		case 'P':
+			pretty = 1;
+			break;
+		default:
+			printf("errror\n");
+		}
+	}
+
+	if (Oflag && mflag) {
+		printf("Cannot specify both -m mask and -O\n");
+		return 0;
+	}
+
+	/* -m overrides any other mask options */
+	if (mflag)
+		mask = m_mask;
+
+	memset(&stx, 0xbf, sizeof(stx));
+	if (statx(AT_FDCWD, file->name, atflag, mask, &stx) < 0) {
+		perror("statx");
+		return 0;
+	}
+
+	if (pretty)
+		pretty_statx(&stx);
+	else
+		raw_statx(&stx);
+
+	return 0;
+}
+
 void
 stat_init(void)
 {
@@ -176,14 +466,25 @@ stat_init(void)
 	stat_cmd.argmax = 1;
 	stat_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
 	stat_cmd.args = _("[-v]");
-	stat_cmd.oneline = _("statistics on the currently open file");
+	stat_cmd.oneline = _("imformation about the currently open file");
 
 	statfs_cmd.name = "statfs";
 	statfs_cmd.cfunc = statfs_f;
 	statfs_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
 	statfs_cmd.oneline =
-		_("statistics on the filesystem of the currently open file");
+ _("information about the filesystem of the currently open file");
+
+	statx_cmd.name = "statx";
+	statx_cmd.cfunc = statx_f;
+	statx_cmd.argmin = 0;
+	statx_cmd.argmax = -1;
+	statx_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
+	statx_cmd.args = _("[-O | -m mask][-FDLAP]");
+	statx_cmd.oneline =
+ _("extended information about the currently open file");
+	statx_cmd.help = statx_help;
 
 	add_command(&stat_cmd);
 	add_command(&statfs_cmd);
+	add_command(&statx_cmd);
 }
diff --git a/io/statx.h b/io/statx.h
new file mode 100644
index 0000000..7e024d1
--- /dev/null
+++ b/io/statx.h
@@ -0,0 +1,137 @@
+#ifndef XFS_IO_STATX_H
+#define XFS_IO_STATX_H
+
+#ifndef STATX_TYPE
+
+/*
+ * Timestamp structure for the timestamps in struct statx.
+ *
+ * tv_sec holds the number of seconds before (negative) or after (positive)
+ * 00:00:00 1st January 1970 UTC.
+ *
+ * tv_nsec holds a number of nanoseconds before (0..-999,999,999 if tv_sec is
+ * negative) or after (0..999,999,999 if tv_sec is positive) the tv_sec time.
+ *
+ * Note that if both tv_sec and tv_nsec are non-zero, then the two values must
+ * either be both positive or both negative.
+ *
+ * __reserved is held in case we need a yet finer resolution.
+ */
+struct statx_timestamp {
+	__s64	tv_sec;
+	__s32	tv_nsec;
+	__s32	__reserved;
+};
+
+/*
+ * Structures for the extended file attribute retrieval system call
+ * (statx()).
+ *
+ * The caller passes a mask of what they're specifically interested in as a
+ * parameter to statx().  What statx() actually got will be indicated in
+ * st_mask upon return.
+ *
+ * For each bit in the mask argument:
+ *
+ * - if the datum is not supported:
+ *
+ *   - the bit will be cleared, and
+ *
+ *   - the datum will be set to an appropriate fabricated value if one is
+ *     available (eg. CIFS can take a default uid and gid), otherwise
+ *
+ *   - the field will be cleared;
+ *
+ * - otherwise, if explicitly requested:
+ *
+ *   - the datum will be synchronised to the server if AT_STATX_FORCE_SYNC is
+ *     set or if the datum is considered out of date, and
+ *
+ *   - the field will be filled in and the bit will be set;
+ *
+ * - otherwise, if not requested, but available in approximate form without any
+ *   effort, it will be filled in anyway, and the bit will be set upon return
+ *   (it might not be up to date, however, and no attempt will be made to
+ *   synchronise the internal state first);
+ *
+ * - otherwise the field and the bit will be cleared before returning.
+ *
+ * Items in STATX_BASIC_STATS may be marked unavailable on return, but they
+ * will have values installed for compatibility purposes so that stat() and
+ * co. can be emulated in userspace.
+ */
+struct statx {
+	/* 0x00 */
+	__u32	stx_mask;	/* What results were written [uncond] */
+	__u32	stx_blksize;	/* Preferred general I/O size [uncond] */
+	__u64	stx_attributes;	/* Flags conveying information about the file [uncond] */
+	/* 0x10 */
+	__u32	stx_nlink;	/* Number of hard links */
+	__u32	stx_uid;	/* User ID of owner */
+	__u32	stx_gid;	/* Group ID of owner */
+	__u16	stx_mode;	/* File mode */
+	__u16	__spare0[1];
+	/* 0x20 */
+	__u64	stx_ino;	/* Inode number */
+	__u64	stx_size;	/* File size */
+	__u64	stx_blocks;	/* Number of 512-byte blocks allocated */
+	__u64	__spare1[1];
+	/* 0x40 */
+	struct statx_timestamp	stx_atime;	/* Last access time */
+	struct statx_timestamp	stx_btime;	/* File creation time */
+	struct statx_timestamp	stx_ctime;	/* Last attribute change time */
+	struct statx_timestamp	stx_mtime;	/* Last data modification time */
+	/* 0x80 */
+	__u32	stx_rdev_major;	/* Device ID of special file [if bdev/cdev] */
+	__u32	stx_rdev_minor;
+	__u32	stx_dev_major;	/* ID of device containing file [uncond] */
+	__u32	stx_dev_minor;
+	/* 0x90 */
+	__u64	__spare2[14];	/* Spare space for future expansion */
+	/* 0x100 */
+};
+
+/*
+ * Flags to be stx_mask
+ *
+ * Query request/result mask for statx() and struct statx::stx_mask.
+ *
+ * These bits should be set in the mask argument of statx() to request
+ * particular items when calling statx().
+ */
+#define STATX_TYPE		0x00000001U	/* Want/got stx_mode & S_IFMT */
+#define STATX_MODE		0x00000002U	/* Want/got stx_mode & ~S_IFMT */
+#define STATX_NLINK		0x00000004U	/* Want/got stx_nlink */
+#define STATX_UID		0x00000008U	/* Want/got stx_uid */
+#define STATX_GID		0x00000010U	/* Want/got stx_gid */
+#define STATX_ATIME		0x00000020U	/* Want/got stx_atime */
+#define STATX_MTIME		0x00000040U	/* Want/got stx_mtime */
+#define STATX_CTIME		0x00000080U	/* Want/got stx_ctime */
+#define STATX_INO		0x00000100U	/* Want/got stx_ino */
+#define STATX_SIZE		0x00000200U	/* Want/got stx_size */
+#define STATX_BLOCKS		0x00000400U	/* Want/got stx_blocks */
+#define STATX_BASIC_STATS	0x000007ffU	/* The stuff in the normal stat struct */
+#define STATX_BTIME		0x00000800U	/* Want/got stx_btime */
+#define STATX_ALL		0x00000fffU	/* All currently supported flags */
+
+/*
+ * Attributes to be found in stx_attributes
+ *
+ * These give information about the features or the state of a file that might
+ * be of use to ordinary userspace programs such as GUIs or ls rather than
+ * specialised tools.
+ *
+ * Note that the flags marked [I] correspond to generic FS_IOC_FLAGS
+ * semantically.  Where possible, the numerical value is picked to correspond
+ * also.
+ */
+#define STATX_ATTR_COMPRESSED		0x00000004 /* [I] File is compressed by the fs */
+#define STATX_ATTR_IMMUTABLE		0x00000010 /* [I] File is marked immutable */
+#define STATX_ATTR_APPEND		0x00000020 /* [I] File is append-only */
+#define STATX_ATTR_NODUMP		0x00000040 /* [I] File is not to be dumped */
+#define STATX_ATTR_ENCRYPTED		0x00000800 /* [I] File requires key to decrypt in fs */
+
+#define STATX_ATTR_AUTOMOUNT		0x00001000 /* Dir: Automount trigger */
+
+#endif /* STATX_TYPE */
+#endif /* XFS_IO_STATX_H */
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 19e1ae4..48b4496 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -880,6 +880,35 @@ and the XFS_IOC_GETXATTR system call on the current file. If the
 option is specified, the atime (last access), mtime
 (last modify), and ctime (last change) timestamps are also displayed.
 .TP
+.BR statx " [ " \-O " | " "\-m mask" " ][ \-" FDLAP " ]"
+Extended information from the statx syscall.
+.RS 1.0i
+.PD 0
+.TP 0.4i
+.B \-m mask
+Specify the field mask for the statx call (default STATX_ALL)
+.TP
+.B \-O
+Remove basic stats (STATX_BASIC_STATS) from default mask
+.TP
+.B \-F
+Force the attributes to be sync'd with the server
+.TP
+.B \-D
+Don't sync attributes with the server
+.TP
+.B \-L
+Follow symlinks (statx link target)
+.TP
+.B \-A
+Suppress terminal automount traversal
+.TP
+.B \-P
+pretty-print results similar to stat(1)
+.TP
+.RE
+.IP
+.TP
 .B statfs
 Selected statistics from
 .BR statfs (2)