Re: Re: [PATCH] udev callout for reading filesystem labels

[Kay Sievers <kay.sievers@vrfy.org>]

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On Fri, May 07, 2004 at 12:59:16AM +0200, Kay Sievers wrote:
> On Fri, May 07, 2004 at 12:44:01AM +0200, Arnd Bergmann wrote:
> > Kay Sievers <kay.sievers@vrfy.org> schrieb am 06.05.2004, 22:18:41:
> > > On Thu, May 06, 2004 at 11:30:23AM +0200, Arnd Bergmann wrote:
> > > > On Thursday 29 April 2004 23:04, Kay Sievers wrote:
> > > 
> > > Sure, we can do this. How much code do we need, for the parsing?
> > 
> > The attachment contains the code from the linux kernel that does
> > the equivalent, somewhat adapted to user interfaces (but probably
> > not functional due to lack of sleep). I'll try to do a working
> > patch tomorrow.
> > 
> > What would you do to find out the disk minor when udev is
> > called for a partition of the disk? Is this handled by udev
> > already or do we need additional logic in the callout program?
> 
> Hmm, we can take libsysfs's get_parent() for the partition, to get the main
> device.

Hi Arnd,
here is a untested first try. udev_volume_id uses libsysfs to get the
major/minor numbers now and therefore relies on the DEVPATH environment
variable instead of the command line options:
If called with the -d option, it tries to read the dasd label from the
main device too.

  KERNEL="sd*", PROGRAM="/sbin/udev_volume_id -l -d", NAME="%c"

Is this what you had in mind?

thanks,
Kay

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diff -Nru a/extras/volume_id/Makefile b/extras/volume_id/Makefile
--- a/extras/volume_id/Makefile	Fri May  7 15:55:58 2004
+++ b/extras/volume_id/Makefile	Fri May  7 15:55:58 2004
@@ -29,8 +29,19 @@
 INSTALL_SCRIPT = ${INSTALL_PROGRAM}
 
 override CFLAGS+=-Wall -fno-builtin
-OBJS = volume_id.o udev_volume_id.o
-HEADERS = volume_id.h
+
+SYSFS =	../../libsysfs/sysfs_bus.o	\
+	../../libsysfs/sysfs_class.o	\
+	../../libsysfs/sysfs_device.o	\
+	../../libsysfs/sysfs_dir.o	\
+	../../libsysfs/sysfs_driver.o	\
+	../../libsysfs/sysfs_utils.o	\
+	../../libsysfs/dlist.o
+
+
+
+OBJS = volume_id.o udev_volume_id.o dasdlabel.o $(SYSFS)
+HEADERS = volume_id.h dasdlabel.h
 
 $(OBJS): $(HEADERS)
 
diff -Nru a/extras/volume_id/dasdlabel.c b/extras/volume_id/dasdlabel.c
--- /dev/null	Wed Dec 31 16:00:00 1969
+++ b/extras/volume_id/dasdlabel.c	Fri May  7 15:55:58 2004
@@ -0,0 +1,163 @@
+/*
+ * dasdlabel.c
+ *
+ */
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+#include "dasdlabel.h"
+
+static unsigned char EBCtoASC[256] =
+{
+/* 0x00  NUL   SOH   STX   ETX  *SEL    HT  *RNL   DEL */
+	0x00, 0x01, 0x02, 0x03, 0x07, 0x09, 0x07, 0x7F,
+/* 0x08  -GE  -SPS  -RPT    VT    FF    CR    SO    SI */
+	0x07, 0x07, 0x07, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
+/* 0x10  DLE   DC1   DC2   DC3  -RES   -NL    BS  -POC
+                                -ENP  ->LF             */
+	0x10, 0x11, 0x12, 0x13, 0x07, 0x0A, 0x08, 0x07,
+/* 0x18  CAN    EM  -UBS  -CU1  -IFS  -IGS  -IRS  -ITB
+                                                  -IUS */
+	0x18, 0x19, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+/* 0x20  -DS  -SOS    FS  -WUS  -BYP    LF   ETB   ESC
+                                -INP                   */
+	0x07, 0x07, 0x1C, 0x07, 0x07, 0x0A, 0x17, 0x1B,
+/* 0x28  -SA  -SFE   -SM  -CSP  -MFA   ENQ   ACK   BEL
+                     -SW                               */ 
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x05, 0x06, 0x07,
+/* 0x30 ----  ----   SYN   -IR   -PP  -TRN  -NBS   EOT */
+	0x07, 0x07, 0x16, 0x07, 0x07, 0x07, 0x07, 0x04,
+/* 0x38 -SBS   -IT  -RFF  -CU3   DC4   NAK  ----   SUB */
+	0x07, 0x07, 0x07, 0x07, 0x14, 0x15, 0x07, 0x1A,
+/* 0x40   SP   RSP           ä              ----       */
+	0x20, 0xFF, 0x83, 0x84, 0x85, 0xA0, 0x07, 0x86,
+/* 0x48                      .     <     (     +     | */
+	0x87, 0xA4, 0x9B, 0x2E, 0x3C, 0x28, 0x2B, 0x7C,
+/* 0x50    &                                      ---- */
+	0x26, 0x82, 0x88, 0x89, 0x8A, 0xA1, 0x8C, 0x07,
+/* 0x58          ß     !     $     *     )     ;       */
+	0x8D, 0xE1, 0x21, 0x24, 0x2A, 0x29, 0x3B, 0xAA,
+/* 0x60    -     /  ----     Ä  ----  ----  ----       */
+	0x2D, 0x2F, 0x07, 0x8E, 0x07, 0x07, 0x07, 0x8F,
+/* 0x68             ----     ,     %     _     >     ? */ 
+	0x80, 0xA5, 0x07, 0x2C, 0x25, 0x5F, 0x3E, 0x3F,
+/* 0x70  ---        ----  ----  ----  ----  ----  ---- */
+	0x07, 0x90, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+/* 0x78    *     `     :     #     @     '     =     " */
+	0x70, 0x60, 0x3A, 0x23, 0x40, 0x27, 0x3D, 0x22,
+/* 0x80    *     a     b     c     d     e     f     g */
+	0x07, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
+/* 0x88    h     i              ----  ----  ----       */
+	0x68, 0x69, 0xAE, 0xAF, 0x07, 0x07, 0x07, 0xF1,
+/* 0x90    °     j     k     l     m     n     o     p */
+	0xF8, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70,
+/* 0x98    q     r                    ----        ---- */
+	0x71, 0x72, 0xA6, 0xA7, 0x91, 0x07, 0x92, 0x07,
+/* 0xA0          ~     s     t     u     v     w     x */
+	0xE6, 0x7E, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
+/* 0xA8    y     z              ----  ----  ----  ---- */
+	0x79, 0x7A, 0xAD, 0xAB, 0x07, 0x07, 0x07, 0x07,
+/* 0xB0    ^                    ----     §  ----       */
+	0x5E, 0x9C, 0x9D, 0xFA, 0x07, 0x07, 0x07, 0xAC,
+/* 0xB8       ----     [     ]  ----  ----  ----  ---- */
+	0xAB, 0x07, 0x5B, 0x5D, 0x07, 0x07, 0x07, 0x07,
+/* 0xC0    {     A     B     C     D     E     F     G */
+	0x7B, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
+/* 0xC8    H     I  ----           ö              ---- */
+	0x48, 0x49, 0x07, 0x93, 0x94, 0x95, 0xA2, 0x07,
+/* 0xD0    }     J     K     L     M     N     O     P */
+	0x7D, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50,
+/* 0xD8    Q     R  ----           ü                   */
+	0x51, 0x52, 0x07, 0x96, 0x81, 0x97, 0xA3, 0x98,
+/* 0xE0    \           S     T     U     V     W     X */
+	0x5C, 0xF6, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
+/* 0xE8    Y     Z        ----     Ö  ----  ----  ---- */
+	0x59, 0x5A, 0xFD, 0x07, 0x99, 0x07, 0x07, 0x07,
+/* 0xF0    0     1     2     3     4     5     6     7 */
+	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+/* 0xF8    8     9  ----  ----     Ü  ----  ----  ---- */
+	0x38, 0x39, 0x07, 0x07, 0x9A, 0x07, 0x07, 0x07
+};
+
+static void vtoc_ebcdic_dec (unsigned char *source, unsigned char *target, int l) 
+{
+	int i;
+
+	for (i = 0; i < l; i++) 
+		target[i]=EBCtoASC[(unsigned char)(source[i])];
+}
+
+/* 
+ * struct dasd_information_t
+ * represents any data about the data, which is visible to userspace
+ */
+typedef struct dasd_information_t {
+	unsigned int devno;		/* S/390 devno */
+	unsigned int real_devno;	/* for aliases */
+	unsigned int schid;		/* S/390 subchannel identifier */
+	unsigned int cu_type  : 16;	/* from SenseID */
+	unsigned int cu_model :  8;	/* from SenseID */
+	unsigned int dev_type : 16;	/* from SenseID */
+	unsigned int dev_model : 8;	/* from SenseID */
+	unsigned int open_count;
+	unsigned int req_queue_len;
+	unsigned int chanq_len;		/* length of chanq */
+	char type[4];			/* from discipline.name, 'none' for unknown */
+	unsigned int status;		/* current device level */
+	unsigned int label_block;	/* where to find the VOLSER */
+	unsigned int FBA_layout;	/* fixed block size (like AIXVOL) */
+	unsigned int characteristics_size;
+	unsigned int confdata_size;
+	char characteristics[64];	/* from read_device_characteristics */
+	char configuration_data[256];	/* from read_configuration_data */
+} dasd_information_t;
+
+#define _IOC_NRBITS		8
+#define _IOC_TYPEBITS		8
+#define _IOC_SIZEBITS		14
+#define _IOC_DIRBITS		2
+#define _IOC_NRMASK		((1 << _IOC_NRBITS)-1)
+#define _IOC_TYPEMASK		((1 << _IOC_TYPEBITS)-1)
+#define _IOC_SIZEMASK		((1 << _IOC_SIZEBITS)-1)
+#define _IOC_DIRMASK		((1 << _IOC_DIRBITS)-1)
+#define _IOC_NRSHIFT		0
+#define _IOC_TYPESHIFT		(_IOC_NRSHIFT+_IOC_NRBITS)
+#define _IOC_SIZESHIFT		(_IOC_TYPESHIFT+_IOC_TYPEBITS)
+#define _IOC_DIRSHIFT		(_IOC_SIZESHIFT+_IOC_SIZEBITS)
+#define DASD_IOCTL_LETTER	 'D'
+
+#define BIODASDINFO _IOR(DASD_IOCTL_LETTER,1,dasd_information_t)
+#define BLKSSZGET _IO(0x12,104)
+
+int probe_ibm_partition(int fd, char *out)
+{
+	int blocksize;
+	dasd_information_t info;
+	char name[7] = {0,};
+	unsigned char data[16];
+
+	if (ioctl(fd, BIODASDINFO, (unsigned long)&info) != 0)
+		return -1;
+
+	if (ioctl(fd, BLKSSZGET, (unsigned long)&blocksize))
+		return -1;
+
+	lseek(fd, info.label_block * blocksize, SEEK_SET);
+	if (read(fd, &data, 16) != 16)
+		return -1;
+
+	if ((!info.FBA_layout) && (!strcmp(info.type, "ECKD")))
+		strncpy(name, data + 8, 6);
+	else
+		strncpy(name, data + 4, 6);
+
+	vtoc_ebcdic_dec(name, out, 6);
+
+	return 0;
+}
diff -Nru a/extras/volume_id/dasdlabel.h b/extras/volume_id/dasdlabel.h
--- /dev/null	Wed Dec 31 16:00:00 1969
+++ b/extras/volume_id/dasdlabel.h	Fri May  7 15:55:58 2004
@@ -0,0 +1,11 @@
+/*
+ * dasdlabel.h
+ *
+ */
+
+#ifndef _DASDLABEL_H_
+#define _DASDLABEL_H_
+
+extern int probe_ibm_partition(int fd, char *out);
+
+#endif
diff -Nru a/extras/volume_id/udev_volume_id.c b/extras/volume_id/udev_volume_id.c
--- a/extras/volume_id/udev_volume_id.c	Fri May  7 15:55:58 2004
+++ b/extras/volume_id/udev_volume_id.c	Fri May  7 15:55:58 2004
@@ -4,7 +4,7 @@
  * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
  *
  *	sample udev rule for creation of a symlink with the filsystem uuid:
- *	KERNEL="sd*", PROGRAM="/sbin/udev_volume_id -M%M -m%m -u", SYMLINK="%c"
+ *	KERNEL="sd*", PROGRAM="/sbin/udev_volume_id -u", SYMLINK="%c"
  *
  *	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
@@ -25,19 +25,58 @@
 #include <stdlib.h>
 #include <unistd.h>
 
+#include "../../udev_lib.h"
+#include "../../libsysfs/sysfs/libsysfs.h"
 #include "volume_id.h"
+#include "dasdlabel.h"
 
-int main(int argc, char *argv[])
+static struct volume_id *open_classdev(struct sysfs_class_device *class_dev)
 {
 	struct volume_id *vid;
-	const char help[] = "usage: udev_volume_id -m<minor> -M<major> [-t|-l|-u]\n";
-	int major = -1;
-	int minor = -1;
-	char *tail;
-	static const char short_options[] = "M:m:htlu";
+	struct sysfs_attribute *attr;
+	int major, minor;
+
+	attr = sysfs_get_classdev_attr(class_dev, "dev");
+
+	if (attr == NULL) {
+		printf("error reading 'dev' attribute\n");
+		return NULL;
+	}
+
+	if (sscanf(attr->value, "%u:%u", &major, &minor) != 2) {
+		printf("error getting major/minor number\n");
+		return NULL;
+	}
+
+	vid = volume_id_open_dev_t(makedev(major, minor));
+	if (vid == NULL) {
+		printf("error open volume\n");
+		return NULL;
+	}
+
+	return vid;
+}
+
+int main(int argc, char *argv[])
+{
+	const char help[] = "usage: udev_volume_id [-t|-l|-u|-d]\n"
+			    "       -t filesystem type\n"
+			    "       -l filesystem label\n"
+			    "       -u filesystem uuid\n"
+			    "       -d also try to read dasd label from parent device\n"
+			    "\n";
+	static const char short_options[] = "htlud";
 	int option;
+	char sysfs_path[SYSFS_PATH_MAX];
+	char dev_path[SYSFS_PATH_MAX];
+	struct sysfs_class_device *class_dev = NULL;
+	struct sysfs_class_device *class_dev_parent = NULL;
+	struct volume_id *vid = NULL;
+	char *devpath;
 	char print = '\0';
-	int rc;
+	int dasd = 0;
+	char dasd_label[7];
+	int rc = 1;
 
 
 	while (1) {
@@ -46,29 +85,18 @@
 			break;
 
 		switch (option) {
-		case 'M':
-			major = (int) strtoul(optarg, &tail, 10);
-			if (tail[0] != '\0') {
-				printf("invalid major\n");
-				exit(1);
-			}
-			break;
-		case 'm':
-			minor = (int) strtoul(optarg, &tail, 10);
-			if (tail[0] != '\0') {
-				printf("invalid minor\n");
-				exit(1);
-			}
-			break;
 		case 't':
 			print = 't';
-			break;
+			continue;
 		case 'l':
 			print = 'l';
-			break;
+			continue;
 		case 'u':
 			print = 'u';
-			break;
+			continue;
+		case 'd':
+			dasd = 1;
+			continue;
 		case 'h':
 		case '?':
 		default:
@@ -77,23 +105,57 @@
 		}
 	}
 
-	if (major == -1 || minor == -1) {
-		printf(help);
-		exit(1);
+	devpath = getenv("DEVPATH");
+	if (devpath == NULL) {
+		printf("error DEVPATH empty\n");
+		goto exit;
 	}
 
-	vid = volume_id_open_dev_t(makedev(major, minor));
-	if (vid == NULL) {
-		printf("error open volume\n");
-		exit(1);
+	if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
+		printf("error getting sysfs mount path\n");
+		goto exit;
 	}
 
-	rc = volume_id_probe(vid, ALL);
-	if (rc != 0) {
-		printf("error probing volume\n");
-		exit(1);
+	strfieldcpy(dev_path, sysfs_path);
+	strfieldcat(dev_path, devpath);
+
+	class_dev = sysfs_open_class_device_path(dev_path);
+	if (class_dev == NULL) {
+		printf("error getting class device\n");
+		goto exit;
+	}
+
+	vid = open_classdev(class_dev);
+	if (vid != NULL) {
+		if (volume_id_probe(vid, ALL) == 0)
+			goto print;
 	}
 
+	if (dasd == 0)
+		goto exit;
+
+	/* if we are on a partition, close it and open main block device */
+	class_dev_parent = sysfs_get_classdev_parent(class_dev);
+	if (class_dev_parent != NULL) {
+		volume_id_close(vid);
+		vid = open_classdev(class_dev_parent);
+		if (vid == NULL) {
+			printf("error open main block device\n");
+			goto exit;
+		}
+	}
+
+	if (probe_ibm_partition(vid->fd, dasd_label) == 0) {
+		vid->fs_name = "dasd";
+		strncpy(vid->label_string, dasd_label, 6);
+		goto print;
+	}
+
+	printf("unknown volume type\n");
+	goto exit;
+
+
+print:
 	switch (print) {
 	case 't':
 		printf("%s\n", vid->fs_name);
@@ -114,7 +176,10 @@
 		printf("U:%s\n", vid->uuid_string);
 	}
 
-	volume_id_close(vid);
-
-	exit(0);
+exit:
+	if (class_dev != NULL)
+		sysfs_close_class_device(class_dev);
+	if (vid != NULL)
+		volume_id_close(vid);
+	exit(rc);
 }
diff -Nru a/extras/volume_id/volume_id.c b/extras/volume_id/volume_id.c
--- a/extras/volume_id/volume_id.c	Fri May  7 15:55:58 2004
+++ b/extras/volume_id/volume_id.c	Fri May  7 15:55:58 2004
@@ -839,10 +839,11 @@
 	char tmp_node[VOLUME_ID_PATH_MAX];
 
 	snprintf(tmp_node, VOLUME_ID_PATH_MAX,
-		 "/tmp/volume-%u-%u", major(devt), minor(devt));
+		 "/tmp/volume-%u-%u-%u", getpid(), major(devt), minor(devt));
 	tmp_node[VOLUME_ID_PATH_MAX] = '\0';
 
 	/* create tempory node to open the block device */
+	unlink(tmp_node);
 	if (mknod(tmp_node, (S_IFBLK | 0600), devt) != 0)
 		return NULL;