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-rw-r--r--lib/blkdev.c483
1 files changed, 483 insertions, 0 deletions
diff --git a/lib/blkdev.c b/lib/blkdev.c
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index 0000000..cc1eea3
--- /dev/null
+++ b/lib/blkdev.c
@@ -0,0 +1,483 @@
+/*
+ * No copyright is claimed. This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Karel Zak <kzak@redhat.com>
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/file.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <stdint.h>
+
+#ifdef HAVE_LINUX_FD_H
+#include <linux/fd.h>
+#endif
+
+#ifdef HAVE_LINUX_BLKZONED_H
+#include <linux/blkzoned.h>
+#endif
+
+#ifdef HAVE_SYS_DISKLABEL_H
+#include <sys/disklabel.h>
+#endif
+
+#ifdef HAVE_SYS_DISK_H
+# include <sys/disk.h>
+#endif
+
+#ifndef EBADFD
+# define EBADFD 77 /* File descriptor in bad state */
+#endif
+
+#include "blkdev.h"
+#include "c.h"
+#include "linux_version.h"
+#include "fileutils.h"
+#include "nls.h"
+
+static long
+blkdev_valid_offset (int fd, off_t offset) {
+ char ch;
+
+ if (lseek (fd, offset, 0) < 0)
+ return 0;
+ if (read (fd, &ch, 1) < 1)
+ return 0;
+ return 1;
+}
+
+int is_blkdev(int fd)
+{
+ struct stat st;
+ return (fstat(fd, &st) == 0 && S_ISBLK(st.st_mode));
+}
+
+off_t
+blkdev_find_size (int fd) {
+ uintmax_t high, low = 0;
+
+ for (high = 1024; blkdev_valid_offset (fd, high); ) {
+ if (high == UINTMAX_MAX)
+ return -1;
+
+ low = high;
+
+ if (high >= UINTMAX_MAX/2)
+ high = UINTMAX_MAX;
+ else
+ high *= 2;
+ }
+
+ while (low < high - 1)
+ {
+ uintmax_t mid = (low + high) / 2;
+
+ if (blkdev_valid_offset (fd, mid))
+ low = mid;
+ else
+ high = mid;
+ }
+ blkdev_valid_offset (fd, 0);
+ return (low + 1);
+}
+
+/* get size in bytes */
+int
+blkdev_get_size(int fd, unsigned long long *bytes)
+{
+#ifdef DKIOCGETBLOCKCOUNT
+ /* Apple Darwin */
+ if (ioctl(fd, DKIOCGETBLOCKCOUNT, bytes) >= 0) {
+ *bytes <<= 9;
+ return 0;
+ }
+#endif
+
+#ifdef BLKGETSIZE64
+ if (ioctl(fd, BLKGETSIZE64, bytes) >= 0)
+ return 0;
+#endif
+
+#ifdef BLKGETSIZE
+ {
+ unsigned long size;
+
+ if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
+ *bytes = ((unsigned long long)size << 9);
+ return 0;
+ }
+ }
+
+#endif /* BLKGETSIZE */
+
+#ifdef DIOCGMEDIASIZE
+ /* FreeBSD */
+ if (ioctl(fd, DIOCGMEDIASIZE, bytes) >= 0)
+ return 0;
+#endif
+
+#ifdef FDGETPRM
+ {
+ struct floppy_struct this_floppy;
+
+ if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
+ *bytes = ((unsigned long long) this_floppy.size) << 9;
+ return 0;
+ }
+ }
+#endif /* FDGETPRM */
+
+#if defined(HAVE_SYS_DISKLABEL_H) && defined(DIOCGDINFO)
+ {
+ /*
+ * This code works for FreeBSD 4.11 i386, except for the full device
+ * (such as /dev/ad0). It doesn't work properly for newer FreeBSD
+ * though. FreeBSD >= 5.0 should be covered by the DIOCGMEDIASIZE
+ * above however.
+ *
+ * Note that FreeBSD >= 4.0 has disk devices as unbuffered (raw,
+ * character) devices, so we need to check for S_ISCHR, too.
+ */
+ int part = -1;
+ struct disklabel lab;
+ struct partition *pp;
+ struct stat st;
+
+ if ((fstat(fd, &st) >= 0) &&
+ (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode)))
+ part = st.st_rdev & 7;
+
+ if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
+ pp = &lab.d_partitions[part];
+ if (pp->p_size) {
+ *bytes = pp->p_size << 9;
+ return 0;
+ }
+ }
+ }
+#endif /* defined(HAVE_SYS_DISKLABEL_H) && defined(DIOCGDINFO) */
+
+ {
+ struct stat st;
+
+ if (fstat(fd, &st) == 0 && S_ISREG(st.st_mode)) {
+ *bytes = st.st_size;
+ return 0;
+ }
+ if (!S_ISBLK(st.st_mode))
+ return -1;
+ }
+
+ *bytes = blkdev_find_size(fd);
+ return 0;
+}
+
+/* get 512-byte sector count */
+int
+blkdev_get_sectors(int fd, unsigned long long *sectors)
+{
+ unsigned long long bytes;
+
+ if (blkdev_get_size(fd, &bytes) == 0) {
+ *sectors = (bytes >> 9);
+ return 0;
+ }
+
+ return -1;
+}
+
+/*
+ * Get logical sector size.
+ *
+ * This is the smallest unit the storage device can
+ * address. It is typically 512 bytes.
+ */
+#ifdef BLKSSZGET
+int blkdev_get_sector_size(int fd, int *sector_size)
+{
+ if (ioctl(fd, BLKSSZGET, sector_size) >= 0)
+ return 0;
+ return -1;
+}
+#else
+int blkdev_get_sector_size(int fd __attribute__((__unused__)), int *sector_size)
+{
+ *sector_size = DEFAULT_SECTOR_SIZE;
+ return 0;
+}
+#endif
+
+/*
+ * Get physical block device size. The BLKPBSZGET is supported since Linux
+ * 2.6.32. For old kernels is probably the best to assume that physical sector
+ * size is the same as logical sector size.
+ *
+ * Example:
+ *
+ * rc = blkdev_get_physector_size(fd, &physec);
+ * if (rc || physec == 0) {
+ * rc = blkdev_get_sector_size(fd, &physec);
+ * if (rc)
+ * physec = DEFAULT_SECTOR_SIZE;
+ * }
+ */
+#ifdef BLKPBSZGET
+int blkdev_get_physector_size(int fd, int *sector_size)
+{
+ if (ioctl(fd, BLKPBSZGET, sector_size) >= 0)
+ {
+ return 0;
+ }
+ return -1;
+}
+#else
+int blkdev_get_physector_size(int fd __attribute__((__unused__)), int *sector_size)
+{
+ *sector_size = DEFAULT_SECTOR_SIZE;
+ return 0;
+}
+#endif
+
+/*
+ * Return the alignment status of a device
+ */
+#ifdef BLKALIGNOFF
+int blkdev_is_misaligned(int fd)
+{
+ int aligned;
+
+ if (ioctl(fd, BLKALIGNOFF, &aligned) < 0)
+ return 0; /* probably kernel < 2.6.32 */
+ /*
+ * Note that kernel returns -1 as alignment offset if no compatible
+ * sizes and alignments exist for stacked devices
+ */
+ return aligned != 0 ? 1 : 0;
+}
+#else
+int blkdev_is_misaligned(int fd __attribute__((__unused__)))
+{
+ return 0;
+}
+#endif
+
+int open_blkdev_or_file(const struct stat *st, const char *name, const int oflag)
+{
+ int fd;
+
+ if (S_ISBLK(st->st_mode)) {
+ fd = open(name, oflag | O_EXCL);
+ } else
+ fd = open(name, oflag);
+ if (-1 < fd && !is_same_inode(fd, st)) {
+ close(fd);
+ errno = EBADFD;
+ return -1;
+ }
+ if (-1 < fd && S_ISBLK(st->st_mode) && blkdev_is_misaligned(fd))
+ warnx(_("warning: %s is misaligned"), name);
+ return fd;
+}
+
+#ifdef CDROM_GET_CAPABILITY
+int blkdev_is_cdrom(int fd)
+{
+ int ret;
+
+ if ((ret = ioctl(fd, CDROM_GET_CAPABILITY, NULL)) < 0)
+ return 0;
+
+ return ret;
+}
+#else
+int blkdev_is_cdrom(int fd __attribute__((__unused__)))
+{
+ return 0;
+}
+#endif
+
+/*
+ * Get kernel's interpretation of the device's geometry.
+ *
+ * Returns the heads and sectors - but not cylinders
+ * as it's truncated for disks with more than 65535 tracks.
+ *
+ * Note that this is deprecated in favor of LBA addressing.
+ */
+#ifdef HDIO_GETGEO
+int blkdev_get_geometry(int fd, unsigned int *h, unsigned int *s)
+{
+ struct hd_geometry geometry;
+
+ if (ioctl(fd, HDIO_GETGEO, &geometry) == 0) {
+ *h = geometry.heads;
+ *s = geometry.sectors;
+ return 0;
+ }
+#else
+int blkdev_get_geometry(int fd __attribute__((__unused__)),
+ unsigned int *h, unsigned int *s)
+{
+ *h = 0;
+ *s = 0;
+#endif
+ return -1;
+}
+
+/*
+ * Convert scsi type to human readable string.
+ */
+const char *blkdev_scsi_type_to_name(int type)
+{
+ switch (type) {
+ case SCSI_TYPE_DISK:
+ return "disk";
+ case SCSI_TYPE_TAPE:
+ return "tape";
+ case SCSI_TYPE_PRINTER:
+ return "printer";
+ case SCSI_TYPE_PROCESSOR:
+ return "processor";
+ case SCSI_TYPE_WORM:
+ return "worm";
+ case SCSI_TYPE_ROM:
+ return "rom";
+ case SCSI_TYPE_SCANNER:
+ return "scanner";
+ case SCSI_TYPE_MOD:
+ return "mo-disk";
+ case SCSI_TYPE_MEDIUM_CHANGER:
+ return "changer";
+ case SCSI_TYPE_COMM:
+ return "comm";
+ case SCSI_TYPE_RAID:
+ return "raid";
+ case SCSI_TYPE_ENCLOSURE:
+ return "enclosure";
+ case SCSI_TYPE_RBC:
+ return "rbc";
+ case SCSI_TYPE_OSD:
+ return "osd";
+ case SCSI_TYPE_NO_LUN:
+ return "no-lun";
+ default:
+ break;
+ }
+ return NULL;
+}
+
+/* return 0 on success */
+int blkdev_lock(int fd, const char *devname, const char *lockmode)
+{
+ int oper, rc, msg = 0;
+
+ if (!lockmode)
+ lockmode = getenv("LOCK_BLOCK_DEVICE");
+ if (!lockmode)
+ return 0;
+
+ if (strcasecmp(lockmode, "yes") == 0 ||
+ strcmp(lockmode, "1") == 0)
+ oper = LOCK_EX;
+
+ else if (strcasecmp(lockmode, "nonblock") == 0)
+ oper = LOCK_EX | LOCK_NB;
+
+ else if (strcasecmp(lockmode, "no") == 0 ||
+ strcmp(lockmode, "0") == 0)
+ return 0;
+ else {
+ warnx(_("unsupported lock mode: %s"), lockmode);
+ return -EINVAL;
+ }
+
+ if (!(oper & LOCK_NB)) {
+ /* Try non-block first to provide message */
+ rc = flock(fd, oper | LOCK_NB);
+ if (rc == 0)
+ return 0;
+ if (rc != 0 && errno == EWOULDBLOCK) {
+ fprintf(stderr, _("%s: %s: device already locked, waiting to get lock ... "),
+ program_invocation_short_name, devname);
+ msg = 1;
+ }
+ }
+ rc = flock(fd, oper);
+ if (rc != 0) {
+ switch (errno) {
+ case EWOULDBLOCK: /* LOCK_NB */
+ warnx(_("%s: device already locked"), devname);
+ break;
+ default:
+ warn(_("%s: failed to get lock"), devname);
+ }
+ } else if (msg)
+ fprintf(stderr, _("OK\n"));
+ return rc;
+}
+
+#ifdef HAVE_LINUX_BLKZONED_H
+struct blk_zone_report *blkdev_get_zonereport(int fd, uint64_t sector, uint32_t nzones)
+{
+ struct blk_zone_report *rep;
+ size_t rep_size;
+ int ret;
+
+ rep_size = sizeof(struct blk_zone_report) + sizeof(struct blk_zone) * 2;
+ rep = calloc(1, rep_size);
+ if (!rep)
+ return NULL;
+
+ rep->sector = sector;
+ rep->nr_zones = nzones;
+
+ ret = ioctl(fd, BLKREPORTZONE, rep);
+ if (ret || rep->nr_zones != nzones) {
+ free(rep);
+ return NULL;
+ }
+
+ return rep;
+}
+#endif
+
+
+#ifdef TEST_PROGRAM_BLKDEV
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+int
+main(int argc, char **argv)
+{
+ unsigned long long bytes;
+ unsigned long long sectors;
+ int sector_size, phy_sector_size;
+ int fd;
+
+ if (argc != 2) {
+ fprintf(stderr, "usage: %s device\n", argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
+ if ((fd = open(argv[1], O_RDONLY|O_CLOEXEC)) < 0)
+ err(EXIT_FAILURE, "open %s failed", argv[1]);
+
+ if (blkdev_get_size(fd, &bytes) < 0)
+ err(EXIT_FAILURE, "blkdev_get_size() failed");
+ if (blkdev_get_sectors(fd, &sectors) < 0)
+ err(EXIT_FAILURE, "blkdev_get_sectors() failed");
+ if (blkdev_get_sector_size(fd, &sector_size) < 0)
+ err(EXIT_FAILURE, "blkdev_get_sector_size() failed");
+ if (blkdev_get_physector_size(fd, &phy_sector_size) < 0)
+ err(EXIT_FAILURE, "blkdev_get_physector_size() failed");
+
+ printf(" bytes: %llu\n", bytes);
+ printf(" sectors: %llu\n", sectors);
+ printf(" sector size: %d\n", sector_size);
+ printf("phy-sector size: %d\n", phy_sector_size);
+
+ return EXIT_SUCCESS;
+}
+#endif /* TEST_PROGRAM_BLKDEV */