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-rw-r--r--grub-core/osdep/linux/hostdisk.c465
1 files changed, 465 insertions, 0 deletions
diff --git a/grub-core/osdep/linux/hostdisk.c b/grub-core/osdep/linux/hostdisk.c
new file mode 100644
index 0000000..da62f92
--- /dev/null
+++ b/grub-core/osdep/linux/hostdisk.c
@@ -0,0 +1,465 @@
+/* hostdisk.c - emulate biosdisk */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 1999,2000,2001,2002,2003,2004,2006,2007,2008,2009,2010,2011,2012,2013 Free Software Foundation, Inc.
+ *
+ * GRUB 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config-util.h>
+
+#include <grub/disk.h>
+#include <grub/partition.h>
+#include <grub/msdos_partition.h>
+#include <grub/types.h>
+#include <grub/err.h>
+#include <grub/emu/misc.h>
+#include <grub/emu/hostdisk.h>
+#include <grub/emu/getroot.h>
+#include <grub/emu/exec.h>
+#include <grub/misc.h>
+#include <grub/i18n.h>
+#include <grub/list.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <limits.h>
+
+# include <sys/ioctl.h> /* ioctl */
+# include <sys/mount.h>
+# ifndef BLKFLSBUF
+# define BLKFLSBUF _IO (0x12,97) /* flush buffer cache */
+# endif /* ! BLKFLSBUF */
+# include <sys/ioctl.h> /* ioctl */
+# ifndef HDIO_GETGEO
+# define HDIO_GETGEO 0x0301 /* get device geometry */
+/* If HDIO_GETGEO is not defined, it is unlikely that hd_geometry is
+ defined. */
+struct hd_geometry
+{
+ unsigned char heads;
+ unsigned char sectors;
+ unsigned short cylinders;
+ unsigned long start;
+};
+# endif /* ! HDIO_GETGEO */
+# ifndef BLKGETSIZE64
+# define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size */
+# endif /* ! BLKGETSIZE64 */
+
+
+grub_int64_t
+grub_util_get_fd_size_os (grub_util_fd_t fd, const char *name, unsigned *log_secsize)
+{
+ unsigned long long nr;
+ unsigned sector_size, log_sector_size;
+
+ if (ioctl (fd, BLKGETSIZE64, &nr))
+ return -1;
+
+ if (ioctl (fd, BLKSSZGET, &sector_size))
+ return -1;
+
+ if (sector_size & (sector_size - 1) || !sector_size)
+ return -1;
+ for (log_sector_size = 0;
+ (1 << log_sector_size) < sector_size;
+ log_sector_size++);
+
+ if (log_secsize)
+ *log_secsize = log_sector_size;
+
+ if (nr & ((1 << log_sector_size) - 1))
+ grub_util_error ("%s", _("unaligned device size"));
+
+ return nr;
+}
+
+static char *
+sysfs_partition_path (const char *dev, const char *entry)
+{
+ const char *argv[7];
+ int fd;
+ pid_t pid;
+ FILE *udevadm;
+ char *buf = NULL;
+ size_t len = 0;
+ char *path = NULL;
+
+ argv[0] = "udevadm";
+ argv[1] = "info";
+ argv[2] = "--query";
+ argv[3] = "path";
+ argv[4] = "--name";
+ argv[5] = dev;
+ argv[6] = NULL;
+
+ pid = grub_util_exec_pipe (argv, &fd);
+
+ if (!pid)
+ return NULL;
+
+ /* Parent. Read udevadm's output. */
+ udevadm = fdopen (fd, "r");
+ if (!udevadm)
+ {
+ grub_util_warn (_("Unable to open stream from %s: %s"),
+ "udevadm", strerror (errno));
+ close (fd);
+ goto out;
+ }
+
+ if (getline (&buf, &len, udevadm) > 0)
+ {
+ char *newline;
+
+ newline = strchr (buf, '\n');
+ if (newline)
+ *newline = '\0';
+ path = xasprintf ("/sys%s/%s", buf, entry);
+ }
+
+out:
+ if (udevadm)
+ fclose (udevadm);
+ waitpid (pid, NULL, 0);
+ free (buf);
+
+ return path;
+}
+
+static int
+sysfs_partition_start (const char *dev, grub_disk_addr_t *start)
+{
+ char *path;
+ FILE *fp;
+ unsigned long long val;
+ int ret = 0;
+
+ path = sysfs_partition_path (dev, "start");
+ if (!path)
+ return 0;
+
+ fp = grub_util_fopen (path, "r");
+ if (!fp)
+ goto out;
+
+ if (fscanf (fp, "%llu", &val) == 1)
+ {
+ *start = (grub_disk_addr_t) val;
+ ret = 1;
+ }
+
+out:
+ free (path);
+ if (fp)
+ fclose (fp);
+
+ return ret;
+}
+
+grub_disk_addr_t
+grub_util_find_partition_start_os (const char *dev)
+{
+ grub_disk_addr_t start = 0;
+ grub_util_fd_t fd;
+ struct hd_geometry hdg;
+
+ if (sysfs_partition_start (dev, &start))
+ return start;
+
+ fd = open (dev, O_RDONLY);
+ if (fd == -1)
+ {
+ grub_error (GRUB_ERR_BAD_DEVICE, N_("cannot open `%s': %s"),
+ dev, strerror (errno));
+ return 0;
+ }
+
+ if (ioctl (fd, HDIO_GETGEO, &hdg))
+ {
+ grub_error (GRUB_ERR_BAD_DEVICE,
+ "cannot get disk geometry of `%s'", dev);
+ close (fd);
+ return 0;
+ }
+
+ close (fd);
+
+ return hdg.start;
+}
+
+/* Cache of partition start sectors for each disk. */
+struct linux_partition_cache
+{
+ struct linux_partition_cache *next;
+ struct linux_partition_cache **prev;
+ char *dev;
+ unsigned long start;
+ int partno;
+};
+
+struct linux_partition_cache *linux_partition_cache_list;
+
+/* Check if we have devfs support. */
+static int
+have_devfs (void)
+{
+ static int dev_devfsd_exists = -1;
+
+ if (dev_devfsd_exists < 0)
+ {
+ struct stat st;
+
+ dev_devfsd_exists = stat ("/dev/.devfsd", &st) == 0;
+ }
+
+ return dev_devfsd_exists;
+}
+
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
+static int
+grub_hostdisk_linux_find_partition (char *dev, grub_disk_addr_t sector)
+{
+ size_t len = strlen (dev);
+ const char *format;
+ char *p;
+ int i;
+ char real_dev[PATH_MAX];
+ struct linux_partition_cache *cache;
+ int missing = 0;
+
+ strcpy(real_dev, dev);
+
+ if (have_devfs () && strcmp (real_dev + len - 5, "/disc") == 0)
+ {
+ p = real_dev + len - 4;
+ format = "part%d";
+ }
+ else if (strncmp (real_dev, "/dev/disk/by-id/",
+ sizeof ("/dev/disk/by-id/") - 1) == 0)
+ {
+ p = real_dev + len;
+ format = "-part%d";
+ }
+ else if (real_dev[len - 1] >= '0' && real_dev[len - 1] <= '9')
+ {
+ p = real_dev + len;
+ format = "p%d";
+ }
+ else
+ {
+ p = real_dev + len;
+ format = "%d";
+ }
+
+ for (cache = linux_partition_cache_list; cache; cache = cache->next)
+ {
+ if (strcmp (cache->dev, dev) == 0 && cache->start == sector)
+ {
+ sprintf (p, format, cache->partno);
+ strcpy (dev, real_dev);
+ return 1;
+ }
+ }
+
+ for (i = 1; i < 10000; i++)
+ {
+ grub_util_fd_t fd;
+ grub_disk_addr_t start;
+ struct stat st;
+
+ sprintf (p, format, i);
+
+ fd = open (real_dev, O_RDONLY);
+ if (fd == -1)
+ {
+ if (missing++ < 10)
+ continue;
+ else
+ return 0;
+ }
+ missing = 0;
+
+ if (fstat (fd, &st) < 0
+ || !grub_util_device_is_mapped_stat (&st)
+ || !grub_util_get_dm_node_linear_info (st.st_rdev, 0, 0, &start))
+ start = grub_util_find_partition_start_os (real_dev);
+ /* We don't care about errors here. */
+ grub_errno = GRUB_ERR_NONE;
+
+ close (fd);
+
+ if (start == sector)
+ {
+ struct linux_partition_cache *new_cache_item;
+
+ new_cache_item = xmalloc (sizeof *new_cache_item);
+ new_cache_item->dev = xstrdup (dev);
+ new_cache_item->start = start;
+ new_cache_item->partno = i;
+ grub_list_push (GRUB_AS_LIST_P (&linux_partition_cache_list),
+ GRUB_AS_LIST (new_cache_item));
+
+ strcpy (dev, real_dev);
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
+void
+grub_hostdisk_flush_initial_buffer (const char *os_dev)
+{
+ grub_util_fd_t fd;
+ struct stat st;
+
+ fd = open (os_dev, O_RDONLY);
+ if (fd >= 0 && fstat (fd, &st) >= 0 && S_ISBLK (st.st_mode))
+ ioctl (fd, BLKFLSBUF, 0);
+ if (fd >= 0)
+ close (fd);
+}
+
+int
+grub_util_fd_open_device (const grub_disk_t disk, grub_disk_addr_t sector, int flags,
+ grub_disk_addr_t *max)
+{
+ grub_util_fd_t fd;
+ struct grub_util_hostdisk_data *data = disk->data;
+
+ *max = ~0ULL;
+
+#ifdef O_LARGEFILE
+ flags |= O_LARGEFILE;
+#endif
+#ifdef O_SYNC
+ flags |= O_SYNC;
+#endif
+#ifdef O_FSYNC
+ flags |= O_FSYNC;
+#endif
+#ifdef O_BINARY
+ flags |= O_BINARY;
+#endif
+#ifdef O_CLOEXEC
+ flags |= O_CLOEXEC;
+#endif
+
+ /* Linux has a bug that the disk cache for a whole disk is not consistent
+ with the one for a partition of the disk. */
+ {
+ int is_partition = 0;
+ char dev[PATH_MAX];
+ grub_disk_addr_t part_start = 0;
+
+ part_start = grub_partition_get_start (disk->partition)
+ >> (disk->log_sector_size - GRUB_DISK_SECTOR_BITS);
+
+ strncpy (dev, grub_util_biosdisk_get_osdev (disk), sizeof (dev) - 1);
+ dev[sizeof(dev) - 1] = '\0';
+ if (disk->partition
+ && strncmp (dev, "/dev/", 5) == 0)
+ {
+ if (sector >= part_start)
+ is_partition = grub_hostdisk_linux_find_partition (dev, part_start);
+ else
+ *max = part_start - sector;
+ }
+
+ reopen:
+
+ if (data->dev && strcmp (data->dev, dev) == 0 &&
+ data->access_mode == (flags & O_ACCMODE))
+ {
+ grub_dprintf ("hostdisk", "reusing open device `%s'\n", dev);
+ fd = data->fd;
+ }
+ else
+ {
+ free (data->dev);
+ data->dev = 0;
+ if (data->fd != -1)
+ {
+ if (data->access_mode == O_RDWR || data->access_mode == O_WRONLY)
+ {
+ fsync (data->fd);
+ if (data->is_disk)
+ ioctl (data->fd, BLKFLSBUF, 0);
+ }
+
+ close (data->fd);
+ data->fd = -1;
+ }
+
+ /* Open the partition. */
+ grub_dprintf ("hostdisk", "opening the device `%s' in open_device()\n", dev);
+ fd = open (dev, flags);
+ if (fd < 0)
+ {
+ grub_error (GRUB_ERR_BAD_DEVICE, N_("cannot open `%s': %s"),
+ dev, strerror (errno));
+ return -1;
+ }
+
+ data->dev = xstrdup (dev);
+ data->access_mode = (flags & O_ACCMODE);
+ data->fd = fd;
+
+ if (data->is_disk)
+ ioctl (data->fd, BLKFLSBUF, 0);
+ }
+
+ if (is_partition)
+ {
+ *max = grub_util_get_fd_size (fd, dev, 0);
+ *max >>= disk->log_sector_size;
+ if (sector - part_start >= *max)
+ {
+ *max = disk->partition->len - (sector - part_start);
+ if (*max == 0)
+ *max = ~0ULL;
+ is_partition = 0;
+ strncpy (dev, grub_util_biosdisk_get_osdev (disk), sizeof (dev) - 1);
+ dev[sizeof(dev) - 1] = '\0';
+ goto reopen;
+ }
+ sector -= part_start;
+ *max -= sector;
+ }
+ }
+
+ if (grub_util_fd_seek (fd, sector << disk->log_sector_size))
+ {
+ close (fd);
+ grub_error (GRUB_ERR_BAD_DEVICE, N_("cannot seek `%s': %s"),
+ grub_util_biosdisk_get_osdev (disk), strerror (errno));
+ return -1;
+ }
+
+ return fd;
+}
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