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-rw-r--r--grub-core/disk/scsi.c766
1 files changed, 766 insertions, 0 deletions
diff --git a/grub-core/disk/scsi.c b/grub-core/disk/scsi.c
new file mode 100644
index 0000000..70767cf
--- /dev/null
+++ b/grub-core/disk/scsi.c
@@ -0,0 +1,766 @@
+/* scsi.c - scsi support. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2008,2009 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 <grub/disk.h>
+#include <grub/dl.h>
+#include <grub/kernel.h>
+#include <grub/misc.h>
+#include <grub/mm.h>
+#include <grub/types.h>
+#include <grub/scsi.h>
+#include <grub/scsicmd.h>
+#include <grub/time.h>
+#include <grub/i18n.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+
+static grub_scsi_dev_t grub_scsi_dev_list;
+
+const char grub_scsi_names[GRUB_SCSI_NUM_SUBSYSTEMS][5] = {
+ [GRUB_SCSI_SUBSYSTEM_USBMS] = "usb",
+ [GRUB_SCSI_SUBSYSTEM_PATA] = "ata",
+ [GRUB_SCSI_SUBSYSTEM_AHCI] = "ahci"
+};
+
+void
+grub_scsi_dev_register (grub_scsi_dev_t dev)
+{
+ dev->next = grub_scsi_dev_list;
+ grub_scsi_dev_list = dev;
+}
+
+void
+grub_scsi_dev_unregister (grub_scsi_dev_t dev)
+{
+ grub_scsi_dev_t *p, q;
+
+ for (p = &grub_scsi_dev_list, q = *p; q; p = &(q->next), q = q->next)
+ if (q == dev)
+ {
+ *p = q->next;
+ break;
+ }
+}
+
+
+/* Check result of previous operation. */
+static grub_err_t
+grub_scsi_request_sense (grub_scsi_t scsi)
+{
+ struct grub_scsi_request_sense rs;
+ struct grub_scsi_request_sense_data rsd;
+ grub_err_t err;
+
+ rs.opcode = grub_scsi_cmd_request_sense;
+ rs.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ rs.reserved1 = 0;
+ rs.reserved2 = 0;
+ rs.alloc_length = 0x12; /* XXX: Hardcoded for now */
+ rs.control = 0;
+ grub_memset (rs.pad, 0, sizeof(rs.pad));
+
+ err = scsi->dev->read (scsi, sizeof (rs), (char *) &rs,
+ sizeof (rsd), (char *) &rsd);
+ if (err)
+ return err;
+
+ return GRUB_ERR_NONE;
+}
+/* Self commenting... */
+static grub_err_t
+grub_scsi_test_unit_ready (grub_scsi_t scsi)
+{
+ struct grub_scsi_test_unit_ready tur;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ tur.opcode = grub_scsi_cmd_test_unit_ready;
+ tur.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ tur.reserved1 = 0;
+ tur.reserved2 = 0;
+ tur.reserved3 = 0;
+ tur.control = 0;
+ grub_memset (tur.pad, 0, sizeof(tur.pad));
+
+ err = scsi->dev->read (scsi, sizeof (tur), (char *) &tur,
+ 0, NULL);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ if (err)
+ return err;
+
+ return GRUB_ERR_NONE;
+}
+
+/* Determine if the device is removable and the type of the device
+ SCSI. */
+static grub_err_t
+grub_scsi_inquiry (grub_scsi_t scsi)
+{
+ struct grub_scsi_inquiry iq;
+ struct grub_scsi_inquiry_data iqd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ iq.opcode = grub_scsi_cmd_inquiry;
+ iq.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ iq.page = 0;
+ iq.reserved = 0;
+ iq.alloc_length = 0x24; /* XXX: Hardcoded for now */
+ iq.control = 0;
+ grub_memset (iq.pad, 0, sizeof(iq.pad));
+
+ err = scsi->dev->read (scsi, sizeof (iq), (char *) &iq,
+ sizeof (iqd), (char *) &iqd);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ if (err)
+ return err;
+
+ scsi->devtype = iqd.devtype & GRUB_SCSI_DEVTYPE_MASK;
+ scsi->removable = iqd.rmb >> GRUB_SCSI_REMOVABLE_BIT;
+
+ return GRUB_ERR_NONE;
+}
+
+/* Read the capacity and block size of SCSI. */
+static grub_err_t
+grub_scsi_read_capacity10 (grub_scsi_t scsi)
+{
+ struct grub_scsi_read_capacity10 rc;
+ struct grub_scsi_read_capacity10_data rcd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ rc.opcode = grub_scsi_cmd_read_capacity10;
+ rc.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ rc.logical_block_addr = 0;
+ rc.reserved1 = 0;
+ rc.reserved2 = 0;
+ rc.PMI = 0;
+ rc.control = 0;
+ rc.pad = 0;
+
+ err = scsi->dev->read (scsi, sizeof (rc), (char *) &rc,
+ sizeof (rcd), (char *) &rcd);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+/* err_sense is ignored for now and Request Sense Data also... */
+
+ if (err)
+ return err;
+
+ scsi->last_block = grub_be_to_cpu32 (rcd.last_block);
+ scsi->blocksize = grub_be_to_cpu32 (rcd.blocksize);
+
+ return GRUB_ERR_NONE;
+}
+
+/* Read the capacity and block size of SCSI. */
+static grub_err_t
+grub_scsi_read_capacity16 (grub_scsi_t scsi)
+{
+ struct grub_scsi_read_capacity16 rc;
+ struct grub_scsi_read_capacity16_data rcd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ rc.opcode = grub_scsi_cmd_read_capacity16;
+ rc.lun = (scsi->lun << GRUB_SCSI_LUN_SHIFT) | 0x10;
+ rc.logical_block_addr = 0;
+ rc.alloc_len = grub_cpu_to_be32_compile_time (sizeof (rcd));
+ rc.PMI = 0;
+ rc.control = 0;
+
+ err = scsi->dev->read (scsi, sizeof (rc), (char *) &rc,
+ sizeof (rcd), (char *) &rcd);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+/* err_sense is ignored for now and Request Sense Data also... */
+
+ if (err)
+ return err;
+
+ scsi->last_block = grub_be_to_cpu64 (rcd.last_block);
+ scsi->blocksize = grub_be_to_cpu32 (rcd.blocksize);
+
+ return GRUB_ERR_NONE;
+}
+
+/* Send a SCSI request for DISK: read SIZE sectors starting with
+ sector SECTOR to BUF. */
+static grub_err_t
+grub_scsi_read10 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_read10 rd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ rd.opcode = grub_scsi_cmd_read10;
+ rd.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ rd.lba = grub_cpu_to_be32 (sector);
+ rd.reserved = 0;
+ rd.size = grub_cpu_to_be16 (size);
+ rd.reserved2 = 0;
+ rd.pad = 0;
+
+ err = scsi->dev->read (scsi, sizeof (rd), (char *) &rd, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+
+/* Send a SCSI request for DISK: read SIZE sectors starting with
+ sector SECTOR to BUF. */
+static grub_err_t
+grub_scsi_read12 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_read12 rd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ rd.opcode = grub_scsi_cmd_read12;
+ rd.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ rd.lba = grub_cpu_to_be32 (sector);
+ rd.size = grub_cpu_to_be32 (size);
+ rd.reserved = 0;
+ rd.control = 0;
+
+ err = scsi->dev->read (scsi, sizeof (rd), (char *) &rd, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+
+/* Send a SCSI request for DISK: read SIZE sectors starting with
+ sector SECTOR to BUF. */
+static grub_err_t
+grub_scsi_read16 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_read16 rd;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ rd.opcode = grub_scsi_cmd_read16;
+ rd.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ rd.lba = grub_cpu_to_be64 (sector);
+ rd.size = grub_cpu_to_be32 (size);
+ rd.reserved = 0;
+ rd.control = 0;
+
+ err = scsi->dev->read (scsi, sizeof (rd), (char *) &rd, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+
+/* Send a SCSI request for DISK: write the data stored in BUF to SIZE
+ sectors starting with SECTOR. */
+static grub_err_t
+grub_scsi_write10 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, const char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_write10 wr;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ wr.opcode = grub_scsi_cmd_write10;
+ wr.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ wr.lba = grub_cpu_to_be32 (sector);
+ wr.reserved = 0;
+ wr.size = grub_cpu_to_be16 (size);
+ wr.reserved2 = 0;
+ wr.pad = 0;
+
+ err = scsi->dev->write (scsi, sizeof (wr), (char *) &wr, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+
+#if 0
+
+/* Send a SCSI request for DISK: write the data stored in BUF to SIZE
+ sectors starting with SECTOR. */
+static grub_err_t
+grub_scsi_write12 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_write12 wr;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ wr.opcode = grub_scsi_cmd_write12;
+ wr.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ wr.lba = grub_cpu_to_be32 (sector);
+ wr.size = grub_cpu_to_be32 (size);
+ wr.reserved = 0;
+ wr.control = 0;
+
+ err = scsi->dev->write (scsi, sizeof (wr), (char *) &wr, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+#endif
+
+/* Send a SCSI request for DISK: write the data stored in BUF to SIZE
+ sectors starting with SECTOR. */
+static grub_err_t
+grub_scsi_write16 (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, const char *buf)
+{
+ grub_scsi_t scsi;
+ struct grub_scsi_write16 wr;
+ grub_err_t err;
+ grub_err_t err_sense;
+
+ scsi = disk->data;
+
+ wr.opcode = grub_scsi_cmd_write16;
+ wr.lun = scsi->lun << GRUB_SCSI_LUN_SHIFT;
+ wr.lba = grub_cpu_to_be64 (sector);
+ wr.size = grub_cpu_to_be32 (size);
+ wr.reserved = 0;
+ wr.control = 0;
+
+ err = scsi->dev->write (scsi, sizeof (wr), (char *) &wr, size * scsi->blocksize, buf);
+
+ /* Each SCSI command should be followed by Request Sense.
+ If not so, many devices STALLs or definitely freezes. */
+ err_sense = grub_scsi_request_sense (scsi);
+ if (err_sense != GRUB_ERR_NONE)
+ grub_errno = err;
+ /* err_sense is ignored for now and Request Sense Data also... */
+
+ return err;
+}
+
+
+
+/* Context for grub_scsi_iterate. */
+struct grub_scsi_iterate_ctx
+{
+ grub_disk_dev_iterate_hook_t hook;
+ void *hook_data;
+};
+
+/* Helper for grub_scsi_iterate. */
+static int
+scsi_iterate (int id, int bus, int luns, void *data)
+{
+ struct grub_scsi_iterate_ctx *ctx = data;
+ int i;
+
+ /* In case of a single LUN, just return `usbX'. */
+ if (luns == 1)
+ {
+ char *sname;
+ int ret;
+ sname = grub_xasprintf ("%s%d", grub_scsi_names[id], bus);
+ if (!sname)
+ return 1;
+ ret = ctx->hook (sname, ctx->hook_data);
+ grub_free (sname);
+ return ret;
+ }
+
+ /* In case of multiple LUNs, every LUN will get a prefix to
+ distinguish it. */
+ for (i = 0; i < luns; i++)
+ {
+ char *sname;
+ int ret;
+ sname = grub_xasprintf ("%s%d%c", grub_scsi_names[id], bus, 'a' + i);
+ if (!sname)
+ return 1;
+ ret = ctx->hook (sname, ctx->hook_data);
+ grub_free (sname);
+ if (ret)
+ return 1;
+ }
+ return 0;
+}
+
+static int
+grub_scsi_iterate (grub_disk_dev_iterate_hook_t hook, void *hook_data,
+ grub_disk_pull_t pull)
+{
+ struct grub_scsi_iterate_ctx ctx = { hook, hook_data };
+ grub_scsi_dev_t p;
+
+ for (p = grub_scsi_dev_list; p; p = p->next)
+ if (p->iterate && (p->iterate) (scsi_iterate, &ctx, pull))
+ return 1;
+
+ return 0;
+}
+
+static grub_err_t
+grub_scsi_open (const char *name, grub_disk_t disk)
+{
+ grub_scsi_dev_t p;
+ grub_scsi_t scsi;
+ grub_err_t err;
+ int lun, bus;
+ grub_uint64_t maxtime;
+ const char *nameend;
+ unsigned id;
+
+ nameend = name + grub_strlen (name) - 1;
+ /* Try to detect a LUN ('a'-'z'), otherwise just use the first
+ LUN. */
+ if (nameend >= name && *nameend >= 'a' && *nameend <= 'z')
+ {
+ lun = *nameend - 'a';
+ nameend--;
+ }
+ else
+ lun = 0;
+
+ while (nameend >= name && grub_isdigit (*nameend))
+ nameend--;
+
+ if (!nameend[1] || !grub_isdigit (nameend[1]))
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "not a SCSI disk");
+
+ bus = grub_strtoul (nameend + 1, 0, 0);
+
+ scsi = grub_malloc (sizeof (*scsi));
+ if (! scsi)
+ return grub_errno;
+
+ for (id = 0; id < ARRAY_SIZE (grub_scsi_names); id++)
+ if (grub_strncmp (grub_scsi_names[id], name, nameend - name) == 0)
+ break;
+
+ if (id == ARRAY_SIZE (grub_scsi_names))
+ {
+ grub_free (scsi);
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "not a SCSI disk");
+ }
+
+ for (p = grub_scsi_dev_list; p; p = p->next)
+ {
+ if (p->open (id, bus, scsi))
+ {
+ grub_errno = GRUB_ERR_NONE;
+ continue;
+ }
+
+ disk->id = grub_make_scsi_id (id, bus, lun);
+ disk->data = scsi;
+ scsi->dev = p;
+ scsi->lun = lun;
+ scsi->bus = bus;
+
+ grub_dprintf ("scsi", "dev opened\n");
+
+ err = grub_scsi_inquiry (scsi);
+ if (err)
+ {
+ grub_free (scsi);
+ grub_dprintf ("scsi", "inquiry failed\n");
+ return err;
+ }
+
+ grub_dprintf ("scsi", "inquiry: devtype=0x%02x removable=%d\n",
+ scsi->devtype, scsi->removable);
+
+ /* Try to be conservative about the device types
+ supported. */
+ if (scsi->devtype != grub_scsi_devtype_direct
+ && scsi->devtype != grub_scsi_devtype_cdrom)
+ {
+ grub_free (scsi);
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE,
+ "unknown SCSI device");
+ }
+
+ /* According to USB MS tests specification, issue Test Unit Ready
+ * until OK */
+ maxtime = grub_get_time_ms () + 5000; /* It is safer value */
+ do
+ {
+ /* Timeout is necessary - for example in case when we have
+ * universal card reader with more LUNs and we have only
+ * one card inserted (or none), so only one LUN (or none)
+ * will be ready - and we want not to hang... */
+ if (grub_get_time_ms () > maxtime)
+ {
+ err = GRUB_ERR_READ_ERROR;
+ grub_free (scsi);
+ grub_dprintf ("scsi", "LUN is not ready - timeout\n");
+ return err;
+ }
+ err = grub_scsi_test_unit_ready (scsi);
+ }
+ while (err == GRUB_ERR_READ_ERROR);
+ /* Reset grub_errno !
+ * It is set to some error code in loop before... */
+ grub_errno = GRUB_ERR_NONE;
+
+ /* Read capacity of media */
+ err = grub_scsi_read_capacity10 (scsi);
+ if (err)
+ {
+ grub_free (scsi);
+ grub_dprintf ("scsi", "READ CAPACITY10 failed\n");
+ return err;
+ }
+
+ if (scsi->last_block == 0xffffffff)
+ {
+ err = grub_scsi_read_capacity16 (scsi);
+ if (err)
+ {
+ grub_free (scsi);
+ grub_dprintf ("scsi", "READ CAPACITY16 failed\n");
+ return err;
+ }
+ }
+
+ disk->total_sectors = scsi->last_block + 1;
+ /* PATA doesn't support more than 32K reads.
+ Not sure about AHCI and USB. If it's confirmed that either of
+ them can do bigger reads reliably this value can be moved to 'scsi'
+ structure. */
+ disk->max_agglomerate = 32768 >> (GRUB_DISK_SECTOR_BITS
+ + GRUB_DISK_CACHE_BITS);
+
+ if (scsi->blocksize & (scsi->blocksize - 1) || !scsi->blocksize)
+ {
+ grub_error (GRUB_ERR_IO, "invalid sector size %d",
+ scsi->blocksize);
+ grub_free (scsi);
+ return grub_errno;
+ }
+ for (disk->log_sector_size = 0;
+ (1U << disk->log_sector_size) < scsi->blocksize;
+ disk->log_sector_size++);
+
+ grub_dprintf ("scsi", "last_block=%" PRIuGRUB_UINT64_T ", blocksize=%u\n",
+ scsi->last_block, scsi->blocksize);
+ grub_dprintf ("scsi", "Disk total sectors = %llu\n",
+ (unsigned long long) disk->total_sectors);
+
+ return GRUB_ERR_NONE;
+ }
+
+ grub_free (scsi);
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "not a SCSI disk");
+}
+
+static void
+grub_scsi_close (grub_disk_t disk)
+{
+ grub_scsi_t scsi;
+
+ scsi = disk->data;
+ if (scsi->dev->close)
+ scsi->dev->close (scsi);
+ grub_free (scsi);
+}
+
+static grub_err_t
+grub_scsi_read (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_scsi_t scsi;
+
+ scsi = disk->data;
+
+ grub_err_t err;
+ /* Depending on the type, select a read function. */
+ switch (scsi->devtype)
+ {
+ case grub_scsi_devtype_direct:
+ if (sector >> 32)
+ err = grub_scsi_read16 (disk, sector, size, buf);
+ else
+ err = grub_scsi_read10 (disk, sector, size, buf);
+ if (err)
+ return err;
+ break;
+
+ case grub_scsi_devtype_cdrom:
+ if (sector >> 32)
+ err = grub_scsi_read16 (disk, sector, size, buf);
+ else
+ err = grub_scsi_read12 (disk, sector, size, buf);
+ if (err)
+ return err;
+ break;
+ }
+
+ return GRUB_ERR_NONE;
+
+#if 0 /* Workaround - it works - but very slowly, from some reason
+ * unknown to me (specially on OHCI). Do not use it. */
+ /* Split transfer requests to device sector size because */
+ /* some devices are not able to transfer more than 512-1024 bytes */
+ grub_err_t err = GRUB_ERR_NONE;
+
+ for ( ; size; size--)
+ {
+ /* Depending on the type, select a read function. */
+ switch (scsi->devtype)
+ {
+ case grub_scsi_devtype_direct:
+ err = grub_scsi_read10 (disk, sector, 1, buf);
+ break;
+
+ case grub_scsi_devtype_cdrom:
+ err = grub_scsi_read12 (disk, sector, 1, buf);
+ break;
+
+ default: /* This should not happen */
+ return GRUB_ERR_READ_ERROR;
+ }
+ if (err)
+ return err;
+ sector++;
+ buf += scsi->blocksize;
+ }
+
+ return err;
+#endif
+}
+
+static grub_err_t
+grub_scsi_write (grub_disk_t disk,
+ grub_disk_addr_t sector,
+ grub_size_t size,
+ const char *buf)
+{
+ grub_scsi_t scsi;
+
+ scsi = disk->data;
+
+ if (scsi->devtype == grub_scsi_devtype_cdrom)
+ return grub_error (GRUB_ERR_IO, N_("cannot write to CD-ROM"));
+
+ grub_err_t err;
+ /* Depending on the type, select a read function. */
+ switch (scsi->devtype)
+ {
+ case grub_scsi_devtype_direct:
+ if (sector >> 32)
+ err = grub_scsi_write16 (disk, sector, size, buf);
+ else
+ err = grub_scsi_write10 (disk, sector, size, buf);
+ if (err)
+ return err;
+ break;
+ }
+
+ return GRUB_ERR_NONE;
+}
+
+
+static struct grub_disk_dev grub_scsi_dev =
+ {
+ .name = "scsi",
+ .id = GRUB_DISK_DEVICE_SCSI_ID,
+ .disk_iterate = grub_scsi_iterate,
+ .disk_open = grub_scsi_open,
+ .disk_close = grub_scsi_close,
+ .disk_read = grub_scsi_read,
+ .disk_write = grub_scsi_write,
+ .next = 0
+ };
+
+GRUB_MOD_INIT(scsi)
+{
+ grub_disk_dev_register (&grub_scsi_dev);
+}
+
+GRUB_MOD_FINI(scsi)
+{
+ grub_disk_dev_unregister (&grub_scsi_dev);
+}