libdasd: Add common DASD ioctl's to the lib

This will avoid code duplication in dasd-related programs.

GitHub-ID: #19

Signed-off-by: Rafael Fonseca <r4f4rfs@gmail.com>
Acked-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
This commit is contained in:
Rafael Fonseca
2017-11-28 00:02:11 +01:00
committed by Stefan Haberland
parent 0348a8443e
commit a5c1923d32
3 changed files with 471 additions and 1 deletions

207
include/lib/dasd_base.h Normal file
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@@ -0,0 +1,207 @@
/*
* dasd_base - Library for DASD related functions
*
* DASD related helper functions for accessing device information
*
* Copyright IBM Corp. 2013, 2017
* Copyright Red Hat Inc. 2017
*
* s390-tools is free software; you can redistribute it and/or modify
* it under the terms of the MIT license. See LICENSE for details.
*/
#ifndef LIB_DASD_BASE_H
#define LIB_DASD_BASE_H
#ifdef __linux__
#include <linux/hdreg.h>
#endif
#include <stdbool.h>
#include <stdio.h>
#include <sys/ioctl.h>
typedef struct dasd_information2_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;
unsigned char characteristics[64];/*from read_device_characteristics */
unsigned char configuration_data[256];/*from read_configuration_data */
unsigned int format; /* format info like formatted/cdl/ldl/... */
unsigned int features; /* dasd features like 'ro',... */
unsigned int reserved0; /* reserved for further use ,... */
unsigned int reserved1; /* reserved for further use ,... */
unsigned int reserved2; /* reserved for further use ,... */
unsigned int reserved3; /* reserved for further use ,... */
unsigned int reserved4; /* reserved for further use ,... */
unsigned int reserved5; /* reserved for further use ,... */
unsigned int reserved6; /* reserved for further use ,... */
unsigned int reserved7; /* reserved for further use ,... */
} dasd_information2_t;
struct dasd_eckd_characteristics {
unsigned short cu_type;
struct {
unsigned char support:2;
unsigned char async:1;
unsigned char reserved:1;
unsigned char cache_info:1;
unsigned char model:3;
} __attribute__ ((packed)) cu_model;
unsigned short dev_type;
unsigned char dev_model;
struct {
unsigned char mult_burst:1;
unsigned char RT_in_LR:1;
unsigned char reserved1:1;
unsigned char RD_IN_LR:1;
unsigned char reserved2:4;
unsigned char reserved3:8;
unsigned char defect_wr:1;
unsigned char XRC_supported:1;
unsigned char reserved4:1;
unsigned char striping:1;
unsigned char reserved5:4;
unsigned char cfw:1;
unsigned char reserved6:2;
unsigned char cache:1;
unsigned char dual_copy:1;
unsigned char dfw:1;
unsigned char reset_alleg:1;
unsigned char sense_down:1;
} __attribute__ ((packed)) facilities;
unsigned char dev_class;
unsigned char unit_type;
unsigned short no_cyl;
unsigned short trk_per_cyl;
unsigned char sec_per_trk;
unsigned char byte_per_track[3];
unsigned short home_bytes;
unsigned char formula;
union {
struct {
unsigned char f1;
unsigned short f2;
unsigned short f3;
} __attribute__ ((packed)) f_0x01;
struct {
unsigned char f1;
unsigned char f2;
unsigned char f3;
unsigned char f4;
unsigned char f5;
} __attribute__ ((packed)) f_0x02;
} __attribute__ ((packed)) factors;
unsigned short first_alt_trk;
unsigned short no_alt_trk;
unsigned short first_dia_trk;
unsigned short no_dia_trk;
unsigned short first_sup_trk;
unsigned short no_sup_trk;
unsigned char MDR_ID;
unsigned char OBR_ID;
unsigned char director;
unsigned char rd_trk_set;
unsigned short max_rec_zero;
unsigned char reserved1;
unsigned char RWANY_in_LR;
unsigned char factor6;
unsigned char factor7;
unsigned char factor8;
unsigned char reserved2[3];
unsigned char reserved3[6];
unsigned int long_no_cyl;
} __attribute__ ((packed));
/*
* struct format_data_t
* represents all data necessary to format a dasd
*/
typedef struct format_data_t {
unsigned int start_unit; /* from track */
unsigned int stop_unit; /* to track */
unsigned int blksize; /* sectorsize */
unsigned int intensity;
} format_data_t;
/*
* struct format_check_t
* represents all data necessary to evaluate the format of
* different tracks of a dasd
*/
typedef struct format_check_t {
/* Input */
struct format_data_t expect;
/* Output */
unsigned int result; /* Error indication (DASD_FMT_ERR_*) */
unsigned int unit; /* Track that is in error */
unsigned int rec; /* Record that is in error */
unsigned int num_records; /* Records in the track in error */
unsigned int blksize; /* Block-size of first record in error */
unsigned int key_length; /* Key length of first record in error */
} format_check_t;
#ifndef __linux__
/* definition from hdreg.h */
struct hd_geometry {
unsigned char heads;
unsigned char sectors;
unsigned short cylinders;
unsigned long start;
};
#endif
#define DASD_IOCTL_LETTER 'D'
/* Disable the volume (for Linux) */
#define BIODASDDISABLE _IO(DASD_IOCTL_LETTER, 0)
/* Enable the volume (for Linux) */
#define BIODASDENABLE _IO(DASD_IOCTL_LETTER, 1)
/* Get information on a dasd device (enhanced) */
#define BIODASDINFO2 _IOR(DASD_IOCTL_LETTER, 3, dasd_information2_t)
/* #define BIODASDFORMAT _IOW(IOCTL_LETTER,0,format_data_t) , deprecated */
#define BIODASDFMT _IOW(DASD_IOCTL_LETTER, 1, format_data_t)
/* Check device format according to format_data_t */
#define BIODASDCHECKFMT _IOWR(DASD_IOCTL_LETTER, 2, format_check_t)
/********************************************************************************
* SECTION: Further IOCTL Definitions (see fs.h and hdreq.h)
*******************************************************************************/
/* get read-only status (0 = read_write) */
#define BLKROGET _IO(0x12, 94)
/* re-read partition table */
#define BLKRRPART _IO(0x12, 95)
/* get block device sector size */
#define BLKSSZGET _IO(0x12, 104)
/* return device size in bytes (u64 *arg) */
#define BLKGETSIZE64 _IOR(0x12, 114, size_t)
#ifndef __linux__ /* from <linux/hdreg.h> */
#define HDIO_GETGEO 0x0301
#endif
int dasd_check_format(const char *device, format_check_t *p);
int dasd_format_disk(int fd, format_data_t *p);
int dasd_disk_disable(const char *device, int *fd);
int dasd_disk_enable(int fd);
int dasd_get_blocksize(const char *device, unsigned int *blksize);
int dasd_get_blocksize_in_bytes(const char *device, unsigned long long *blksize);
int dasd_get_geo(const char *device, struct hd_geometry *geo);
int dasd_get_info(const char *device, dasd_information2_t *info);
int dasd_is_ro(const char *device, bool *ro);
int dasd_reread_partition_table(const char *device, int ntries);
#endif /* LIB_DASD_BASE_H */

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@@ -4,7 +4,7 @@ lib = libdasd.a
all: $(lib)
objects = dasd_sys.o
objects = dasd_sys.o dasd_ioctl.o
$(lib): $(objects) Makefile

263
libdasd/dasd_ioctl.c Normal file
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@@ -0,0 +1,263 @@
/*
* dasd_ioctl - Library for dasd-related ioctls
*
* DASD related helper functions for accessing device information via ioctls
*
* Copyright IBM Corp. 2013, 2017
* Copyright Red Hat Inc. 2017
*
* s390-tools is free software; you can redistribute it and/or modify
* it under the terms of the MIT license. See LICENSE for details.
*/
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "lib/dasd_base.h"
#define COULD_NOT_OPEN_WARN(device) \
warn("Could not open device '%s'", device)
#define COULD_NOT_CLOSE_WARN \
warn("Unable to close device")
#define RUN_IOCTL(fd, req, argp) \
do { \
if (ioctl(fd, req, argp) != 0) { \
int err = errno; \
if (err != EBADF) \
dasd_close_device(fd); \
return err; \
} \
} while (0)
static int dasd_open_device(const char *device, int flags)
{
int fd;
fd = open(device, flags);
if (fd == -1)
COULD_NOT_OPEN_WARN(device);
return fd;
}
static void dasd_close_device(int fd)
{
if (close(fd) != 0)
COULD_NOT_CLOSE_WARN;
}
/*
* Get DASD block size information for device
*
* @param[in] device node device node's name
* @param[out] blksize the block size
*
* @retval 0 in case of success
* @retval errno in case of failure
*
*/
int dasd_get_blocksize(const char *device, unsigned int *blksize)
{
int fd;
fd = dasd_open_device(device, O_RDONLY);
RUN_IOCTL(fd, BLKSSZGET, blksize);
dasd_close_device(fd);
return 0;
}
/*
* Get DASD block size information (in bytes) for device
*
* @param[in] device node device node's name
* @param[out] blksize block size in bytes
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_get_blocksize_in_bytes(const char *device, unsigned long long *blksize)
{
int fd;
fd = dasd_open_device(device, O_RDONLY);
RUN_IOCTL(fd, BLKGETSIZE64, blksize);
dasd_close_device(fd);
return 0;
}
/*
* Get DASD disk information for device
*
* @param[in] device node device node's name
* @param[out] info pointer to dasd information
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_get_info(const char *device, dasd_information2_t *info)
{
int fd;
fd = dasd_open_device(device, O_RDONLY);
RUN_IOCTL(fd, BIODASDINFO2, info);
dasd_close_device(fd);
return 0;
}
/*
* Get DASD disk geometry information for device
*
* @param[in] device node device node's name
* @param[out] geo pointer to device geometry information
*
* @retval errno in case of failure
* @retval 0 in case of success
*/
int dasd_get_geo(const char *device, struct hd_geometry *geo)
{
int fd;
fd = dasd_open_device(device, O_RDONLY);
RUN_IOCTL(fd, HDIO_GETGEO, geo);
dasd_close_device(fd);
return 0;
}
/*
* Get DASD read/write status information for device
*
* @param[in] device node device node's name
* @param[out] ro read-only status (1 for ro, 0 for rw)
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_is_ro(const char *device, bool *ro)
{
int fd, val;
fd = dasd_open_device(device, O_RDWR);
RUN_IOCTL(fd, BLKROGET, &val);
*ro = (val != 0) ? true : false;
return 0;
}
/*
* Disable DASD disk.
*
* @param[in] device node device node's name
*
* @retval 0 in case of success
* @retval errno in case of failure
*
* Note: Before BIODASDFMT can be called, a DASD has to be disabled (or rather
* put into a BASIC state) via BIODASDDISABLE. However, if you disable the DASD,
* close the file descriptor, and then try to reopen it, it won't work as the
* device isn't fully usable anymore. For BIODASDFMT to work, the file
* descriptor opened for BIODASDISABLE has to be kept open until BIODASDFMT has
* finished.
*/
int dasd_disk_disable(const char *device, int *fd)
{
*fd = dasd_open_device(device, O_RDWR);
RUN_IOCTL(*fd, BIODASDDISABLE, NULL);
return 0;
}
/*
* Enable DASD disk
*
* @param[in] device node device node's name
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_disk_enable(int fd)
{
RUN_IOCTL(fd, BIODASDENABLE, NULL);
dasd_close_device(fd);
return 0;
}
/*
* Format DASD disk
*
* @param[in] fd device node's file descriptor
* @param[in] p format options
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_format_disk(int fd, format_data_t *p)
{
RUN_IOCTL(fd, BIODASDFMT, p);
return 0;
}
/*
* Check DASD format
*
* @param[in] device node device node's name
* @param[in] p format params
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_check_format(const char *device, format_check_t *p)
{
int fd;
fd = dasd_open_device(device, O_RDONLY);
RUN_IOCTL(fd, BIODASDCHECKFMT, p);
dasd_close_device(fd);
return 0;
}
/*
* Reread partition table
*
* @param[in] device node device node's name
* @param[in] ntries maximum number of tries
*
* @retval 0 in case of success
* @retval errno in case of failure
*/
int dasd_reread_partition_table(const char *device, int ntries)
{
int i, fd, err = 0;
fd = dasd_open_device(device, O_RDONLY);
/*
* If the BLKRRPART ioctl fails, it is most likely due to the device
* just being in use by udev. So it is worthwhile to retry the ioctl
* after a second as it is likely to succeed.
*/
for (i = 0; i < ntries; i++) {
if (ioctl(fd, BLKRRPART, NULL) != 0) {
err = errno;
sleep(1);
} else {
err = 0;
break;
}
}
dasd_close_device(fd);
return err;
}