Currently, blk_is_read_only() tells whether a given BlockBackend can only be used in read-only mode because its root node is read-only. Some callers actually try to answer a slightly different question: Is the BlockBackend configured to be writable, by taking write permissions on the root node? This can differ, for example, for CD-ROM devices which don't take write permissions, but may be backed by a writable image file. scsi-cd allows write requests to the drive if blk_is_read_only() returns false. However, the write request will immediately run into an assertion failure because the write permission is missing. This patch introduces separate functions for both questions. blk_supports_write_perm() answers the question whether the block node/image file can support writable devices, whereas blk_is_writable() tells whether the BlockBackend is currently configured to be writable. All calls of blk_is_read_only() are converted to one of the two new functions. Fixes: https://bugs.launchpad.net/bugs/1906693 Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210118123448.307825-2-kwolf@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
		
			
				
	
	
		
			793 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			793 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Generic SCSI Device support
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 *
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 * Copyright (c) 2007 Bull S.A.S.
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 * Based on code by Paul Brook
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 * Based on code by Fabrice Bellard
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 *
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 * Written by Laurent Vivier <Laurent.Vivier@bull.net>
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 *
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 * This code is licensed under the LGPL.
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 *
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 */
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#include "qemu/osdep.h"
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#include "qapi/error.h"
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#include "qemu/ctype.h"
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#include "qemu/error-report.h"
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#include "qemu/module.h"
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#include "hw/scsi/scsi.h"
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#include "migration/qemu-file-types.h"
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#include "hw/qdev-properties.h"
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#include "hw/qdev-properties-system.h"
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#include "hw/scsi/emulation.h"
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#include "sysemu/block-backend.h"
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#include "trace.h"
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#ifdef __linux__
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#include <scsi/sg.h>
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#include "scsi/constants.h"
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#ifndef MAX_UINT
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#define MAX_UINT ((unsigned int)-1)
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#endif
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typedef struct SCSIGenericReq {
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    SCSIRequest req;
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    uint8_t *buf;
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    int buflen;
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    int len;
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    sg_io_hdr_t io_header;
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} SCSIGenericReq;
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static void scsi_generic_save_request(QEMUFile *f, SCSIRequest *req)
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{
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    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
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    qemu_put_sbe32s(f, &r->buflen);
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    if (r->buflen && r->req.cmd.mode == SCSI_XFER_TO_DEV) {
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        assert(!r->req.sg);
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        qemu_put_buffer(f, r->buf, r->req.cmd.xfer);
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    }
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}
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static void scsi_generic_load_request(QEMUFile *f, SCSIRequest *req)
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{
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    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
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    qemu_get_sbe32s(f, &r->buflen);
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    if (r->buflen && r->req.cmd.mode == SCSI_XFER_TO_DEV) {
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        assert(!r->req.sg);
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        qemu_get_buffer(f, r->buf, r->req.cmd.xfer);
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    }
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}
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static void scsi_free_request(SCSIRequest *req)
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{
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    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
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    g_free(r->buf);
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}
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/* Helper function for command completion.  */
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static void scsi_command_complete_noio(SCSIGenericReq *r, int ret)
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{
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    int status;
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    SCSISense sense;
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    assert(r->req.aiocb == NULL);
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    if (r->req.io_canceled) {
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        scsi_req_cancel_complete(&r->req);
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        goto done;
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    }
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    status = sg_io_sense_from_errno(-ret, &r->io_header, &sense);
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    if (status == CHECK_CONDITION) {
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        if (r->io_header.driver_status & SG_ERR_DRIVER_SENSE) {
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            r->req.sense_len = r->io_header.sb_len_wr;
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        } else {
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            scsi_req_build_sense(&r->req, sense);
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        }
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    }
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    trace_scsi_generic_command_complete_noio(r, r->req.tag, status);
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    scsi_req_complete(&r->req, status);
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done:
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    scsi_req_unref(&r->req);
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}
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static void scsi_command_complete(void *opaque, int ret)
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{
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    SCSIGenericReq *r = (SCSIGenericReq *)opaque;
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    SCSIDevice *s = r->req.dev;
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    assert(r->req.aiocb != NULL);
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    r->req.aiocb = NULL;
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    aio_context_acquire(blk_get_aio_context(s->conf.blk));
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    scsi_command_complete_noio(r, ret);
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    aio_context_release(blk_get_aio_context(s->conf.blk));
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}
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static int execute_command(BlockBackend *blk,
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                           SCSIGenericReq *r, int direction,
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                           BlockCompletionFunc *complete)
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{
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    r->io_header.interface_id = 'S';
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    r->io_header.dxfer_direction = direction;
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    r->io_header.dxferp = r->buf;
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    r->io_header.dxfer_len = r->buflen;
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    r->io_header.cmdp = r->req.cmd.buf;
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    r->io_header.cmd_len = r->req.cmd.len;
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    r->io_header.mx_sb_len = sizeof(r->req.sense);
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    r->io_header.sbp = r->req.sense;
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    r->io_header.timeout = MAX_UINT;
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    r->io_header.usr_ptr = r;
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    r->io_header.flags |= SG_FLAG_DIRECT_IO;
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    r->req.aiocb = blk_aio_ioctl(blk, SG_IO, &r->io_header, complete, r);
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    if (r->req.aiocb == NULL) {
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        return -EIO;
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    }
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    return 0;
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}
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static void scsi_handle_inquiry_reply(SCSIGenericReq *r, SCSIDevice *s)
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{
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    uint8_t page, page_idx;
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    /*
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     *  EVPD set to zero returns the standard INQUIRY data.
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     *
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     *  Check if scsi_version is unset (-1) to avoid re-defining it
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     *  each time an INQUIRY with standard data is received.
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     *  scsi_version is initialized with -1 in scsi_generic_reset
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     *  and scsi_disk_reset, making sure that we'll set the
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     *  scsi_version after a reset. If the version field of the
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     *  INQUIRY response somehow changes after a guest reboot,
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     *  we'll be able to keep track of it.
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     *
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     *  On SCSI-2 and older, first 3 bits of byte 2 is the
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     *  ANSI-approved version, while on later versions the
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     *  whole byte 2 contains the version. Check if we're dealing
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     *  with a newer version and, in that case, assign the
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     *  whole byte.
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     */
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    if (s->scsi_version == -1 && !(r->req.cmd.buf[1] & 0x01)) {
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        s->scsi_version = r->buf[2] & 0x07;
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        if (s->scsi_version > 2) {
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            s->scsi_version = r->buf[2];
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        }
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    }
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    if ((s->type == TYPE_DISK || s->type == TYPE_ZBC) &&
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        (r->req.cmd.buf[1] & 0x01)) {
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        page = r->req.cmd.buf[2];
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        if (page == 0xb0) {
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            uint32_t max_transfer =
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                blk_get_max_transfer(s->conf.blk) / s->blocksize;
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            assert(max_transfer);
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            stl_be_p(&r->buf[8], max_transfer);
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            /* Also take care of the opt xfer len. */
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            stl_be_p(&r->buf[12],
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                    MIN_NON_ZERO(max_transfer, ldl_be_p(&r->buf[12])));
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        } else if (s->needs_vpd_bl_emulation && page == 0x00 && r->buflen >= 4) {
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            /*
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             * Now we're capable of supplying the VPD Block Limits
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             * response if the hardware can't. Add it in the INQUIRY
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             * Supported VPD pages response in case we are using the
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             * emulation for this device.
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             *
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             * This way, the guest kernel will be aware of the support
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             * and will use it to proper setup the SCSI device.
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             *
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             * VPD page numbers must be sorted, so insert 0xb0 at the
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             * right place with an in-place insert.  When the while loop
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             * begins the device response is at r[0] to r[page_idx - 1].
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             */
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            page_idx = lduw_be_p(r->buf + 2) + 4;
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            page_idx = MIN(page_idx, r->buflen);
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            while (page_idx > 4 && r->buf[page_idx - 1] >= 0xb0) {
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                if (page_idx < r->buflen) {
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                    r->buf[page_idx] = r->buf[page_idx - 1];
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                }
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                page_idx--;
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            }
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            if (page_idx < r->buflen) {
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                r->buf[page_idx] = 0xb0;
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            }
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            stw_be_p(r->buf + 2, lduw_be_p(r->buf + 2) + 1);
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        }
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    }
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}
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static int scsi_generic_emulate_block_limits(SCSIGenericReq *r, SCSIDevice *s)
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{
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    int len;
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    uint8_t buf[64];
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    SCSIBlockLimits bl = {
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        .max_io_sectors = blk_get_max_transfer(s->conf.blk) / s->blocksize
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    };
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    memset(r->buf, 0, r->buflen);
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    stb_p(buf, s->type);
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    stb_p(buf + 1, 0xb0);
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    len = scsi_emulate_block_limits(buf + 4, &bl);
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    assert(len <= sizeof(buf) - 4);
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    stw_be_p(buf + 2, len);
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    memcpy(r->buf, buf, MIN(r->buflen, len + 4));
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    r->io_header.sb_len_wr = 0;
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    /*
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    * We have valid contents in the reply buffer but the
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    * io_header can report a sense error coming from
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    * the hardware in scsi_command_complete_noio. Clean
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    * up the io_header to avoid reporting it.
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    */
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    r->io_header.driver_status = 0;
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    r->io_header.status = 0;
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    return r->buflen;
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}
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static void scsi_read_complete(void * opaque, int ret)
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{
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    SCSIGenericReq *r = (SCSIGenericReq *)opaque;
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    SCSIDevice *s = r->req.dev;
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    int len;
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    assert(r->req.aiocb != NULL);
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    r->req.aiocb = NULL;
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    aio_context_acquire(blk_get_aio_context(s->conf.blk));
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    if (ret || r->req.io_canceled) {
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        scsi_command_complete_noio(r, ret);
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        goto done;
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    }
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    len = r->io_header.dxfer_len - r->io_header.resid;
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    trace_scsi_generic_read_complete(r->req.tag, len);
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    r->len = -1;
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    if (r->io_header.driver_status & SG_ERR_DRIVER_SENSE) {
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        SCSISense sense =
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            scsi_parse_sense_buf(r->req.sense, r->io_header.sb_len_wr);
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        /*
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         * Check if this is a VPD Block Limits request that
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         * resulted in sense error but would need emulation.
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         * In this case, emulate a valid VPD response.
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         */
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        if (sense.key == ILLEGAL_REQUEST &&
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            s->needs_vpd_bl_emulation &&
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            r->req.cmd.buf[0] == INQUIRY &&
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            (r->req.cmd.buf[1] & 0x01) &&
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            r->req.cmd.buf[2] == 0xb0) {
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            len = scsi_generic_emulate_block_limits(r, s);
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            /*
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             * It's okay to jup to req_complete: no need to
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             * let scsi_handle_inquiry_reply handle an
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             * INQUIRY VPD BL request we created manually.
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             */
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        }
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        if (sense.key) {
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            goto req_complete;
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        }
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    }
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    if (len == 0) {
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        scsi_command_complete_noio(r, 0);
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        goto done;
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    }
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    /* Snoop READ CAPACITY output to set the blocksize.  */
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    if (r->req.cmd.buf[0] == READ_CAPACITY_10 &&
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        (ldl_be_p(&r->buf[0]) != 0xffffffffU || s->max_lba == 0)) {
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        s->blocksize = ldl_be_p(&r->buf[4]);
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        s->max_lba = ldl_be_p(&r->buf[0]) & 0xffffffffULL;
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    } else if (r->req.cmd.buf[0] == SERVICE_ACTION_IN_16 &&
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               (r->req.cmd.buf[1] & 31) == SAI_READ_CAPACITY_16) {
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        s->blocksize = ldl_be_p(&r->buf[8]);
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        s->max_lba = ldq_be_p(&r->buf[0]);
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    }
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    blk_set_guest_block_size(s->conf.blk, s->blocksize);
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    /*
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     * Patch MODE SENSE device specific parameters if the BDS is opened
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     * readonly.
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     */
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    if ((s->type == TYPE_DISK || s->type == TYPE_TAPE || s->type == TYPE_ZBC) &&
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        !blk_is_writable(s->conf.blk) &&
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        (r->req.cmd.buf[0] == MODE_SENSE ||
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         r->req.cmd.buf[0] == MODE_SENSE_10) &&
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        (r->req.cmd.buf[1] & 0x8) == 0) {
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        if (r->req.cmd.buf[0] == MODE_SENSE) {
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            r->buf[2] |= 0x80;
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        } else  {
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            r->buf[3] |= 0x80;
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        }
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    }
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    if (r->req.cmd.buf[0] == INQUIRY) {
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        scsi_handle_inquiry_reply(r, s);
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    }
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req_complete:
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    scsi_req_data(&r->req, len);
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    scsi_req_unref(&r->req);
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done:
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    aio_context_release(blk_get_aio_context(s->conf.blk));
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}
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/* Read more data from scsi device into buffer.  */
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static void scsi_read_data(SCSIRequest *req)
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{
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    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
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    SCSIDevice *s = r->req.dev;
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    int ret;
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    trace_scsi_generic_read_data(req->tag);
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    /* The request is used as the AIO opaque value, so add a ref.  */
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    scsi_req_ref(&r->req);
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    if (r->len == -1) {
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        scsi_command_complete_noio(r, 0);
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        return;
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    }
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    ret = execute_command(s->conf.blk, r, SG_DXFER_FROM_DEV,
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                          scsi_read_complete);
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    if (ret < 0) {
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        scsi_command_complete_noio(r, ret);
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    }
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}
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static void scsi_write_complete(void * opaque, int ret)
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{
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    SCSIGenericReq *r = (SCSIGenericReq *)opaque;
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    SCSIDevice *s = r->req.dev;
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    trace_scsi_generic_write_complete(ret);
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 | 
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    assert(r->req.aiocb != NULL);
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    r->req.aiocb = NULL;
 | 
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 | 
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    aio_context_acquire(blk_get_aio_context(s->conf.blk));
 | 
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 | 
						|
    if (ret || r->req.io_canceled) {
 | 
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        scsi_command_complete_noio(r, ret);
 | 
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        goto done;
 | 
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    }
 | 
						|
 | 
						|
    if (r->req.cmd.buf[0] == MODE_SELECT && r->req.cmd.buf[4] == 12 &&
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						|
        s->type == TYPE_TAPE) {
 | 
						|
        s->blocksize = (r->buf[9] << 16) | (r->buf[10] << 8) | r->buf[11];
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        trace_scsi_generic_write_complete_blocksize(s->blocksize);
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    }
 | 
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 | 
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    scsi_command_complete_noio(r, ret);
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 | 
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done:
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    aio_context_release(blk_get_aio_context(s->conf.blk));
 | 
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}
 | 
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 | 
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/* Write data to a scsi device.  Returns nonzero on failure.
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   The transfer may complete asynchronously.  */
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static void scsi_write_data(SCSIRequest *req)
 | 
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{
 | 
						|
    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
 | 
						|
    SCSIDevice *s = r->req.dev;
 | 
						|
    int ret;
 | 
						|
 | 
						|
    trace_scsi_generic_write_data(req->tag);
 | 
						|
    if (r->len == 0) {
 | 
						|
        r->len = r->buflen;
 | 
						|
        scsi_req_data(&r->req, r->len);
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /* The request is used as the AIO opaque value, so add a ref.  */
 | 
						|
    scsi_req_ref(&r->req);
 | 
						|
    ret = execute_command(s->conf.blk, r, SG_DXFER_TO_DEV, scsi_write_complete);
 | 
						|
    if (ret < 0) {
 | 
						|
        scsi_command_complete_noio(r, ret);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
/* Return a pointer to the data buffer.  */
 | 
						|
static uint8_t *scsi_get_buf(SCSIRequest *req)
 | 
						|
{
 | 
						|
    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
 | 
						|
 | 
						|
    return r->buf;
 | 
						|
}
 | 
						|
 | 
						|
static void scsi_generic_command_dump(uint8_t *cmd, int len)
 | 
						|
{
 | 
						|
    int i;
 | 
						|
    char *line_buffer, *p;
 | 
						|
 | 
						|
    line_buffer = g_malloc(len * 5 + 1);
 | 
						|
 | 
						|
    for (i = 0, p = line_buffer; i < len; i++) {
 | 
						|
        p += sprintf(p, " 0x%02x", cmd[i]);
 | 
						|
    }
 | 
						|
    trace_scsi_generic_send_command(line_buffer);
 | 
						|
 | 
						|
    g_free(line_buffer);
 | 
						|
}
 | 
						|
 | 
						|
/* Execute a scsi command.  Returns the length of the data expected by the
 | 
						|
   command.  This will be Positive for data transfers from the device
 | 
						|
   (eg. disk reads), negative for transfers to the device (eg. disk writes),
 | 
						|
   and zero if the command does not transfer any data.  */
 | 
						|
 | 
						|
static int32_t scsi_send_command(SCSIRequest *req, uint8_t *cmd)
 | 
						|
{
 | 
						|
    SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
 | 
						|
    SCSIDevice *s = r->req.dev;
 | 
						|
    int ret;
 | 
						|
 | 
						|
    if (trace_event_get_state_backends(TRACE_SCSI_GENERIC_SEND_COMMAND)) {
 | 
						|
        scsi_generic_command_dump(cmd, r->req.cmd.len);
 | 
						|
    }
 | 
						|
 | 
						|
    if (r->req.cmd.xfer == 0) {
 | 
						|
        g_free(r->buf);
 | 
						|
        r->buflen = 0;
 | 
						|
        r->buf = NULL;
 | 
						|
        /* The request is used as the AIO opaque value, so add a ref.  */
 | 
						|
        scsi_req_ref(&r->req);
 | 
						|
        ret = execute_command(s->conf.blk, r, SG_DXFER_NONE,
 | 
						|
                              scsi_command_complete);
 | 
						|
        if (ret < 0) {
 | 
						|
            scsi_command_complete_noio(r, ret);
 | 
						|
            return 0;
 | 
						|
        }
 | 
						|
        return 0;
 | 
						|
    }
 | 
						|
 | 
						|
    if (r->buflen != r->req.cmd.xfer) {
 | 
						|
        g_free(r->buf);
 | 
						|
        r->buf = g_malloc(r->req.cmd.xfer);
 | 
						|
        r->buflen = r->req.cmd.xfer;
 | 
						|
    }
 | 
						|
 | 
						|
    memset(r->buf, 0, r->buflen);
 | 
						|
    r->len = r->req.cmd.xfer;
 | 
						|
    if (r->req.cmd.mode == SCSI_XFER_TO_DEV) {
 | 
						|
        r->len = 0;
 | 
						|
        return -r->req.cmd.xfer;
 | 
						|
    } else {
 | 
						|
        return r->req.cmd.xfer;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static int read_naa_id(const uint8_t *p, uint64_t *p_wwn)
 | 
						|
{
 | 
						|
    int i;
 | 
						|
 | 
						|
    if ((p[1] & 0xF) == 3) {
 | 
						|
        /* NAA designator type */
 | 
						|
        if (p[3] != 8) {
 | 
						|
            return -EINVAL;
 | 
						|
        }
 | 
						|
        *p_wwn = ldq_be_p(p + 4);
 | 
						|
        return 0;
 | 
						|
    }
 | 
						|
 | 
						|
    if ((p[1] & 0xF) == 8) {
 | 
						|
        /* SCSI name string designator type */
 | 
						|
        if (p[3] < 20 || memcmp(&p[4], "naa.", 4)) {
 | 
						|
            return -EINVAL;
 | 
						|
        }
 | 
						|
        if (p[3] > 20 && p[24] != ',') {
 | 
						|
            return -EINVAL;
 | 
						|
        }
 | 
						|
        *p_wwn = 0;
 | 
						|
        for (i = 8; i < 24; i++) {
 | 
						|
            char c = qemu_toupper(p[i]);
 | 
						|
            c -= (c >= '0' && c <= '9' ? '0' : 'A' - 10);
 | 
						|
            *p_wwn = (*p_wwn << 4) | c;
 | 
						|
        }
 | 
						|
        return 0;
 | 
						|
    }
 | 
						|
 | 
						|
    return -EINVAL;
 | 
						|
}
 | 
						|
 | 
						|
int scsi_SG_IO_FROM_DEV(BlockBackend *blk, uint8_t *cmd, uint8_t cmd_size,
 | 
						|
                        uint8_t *buf, uint8_t buf_size)
 | 
						|
{
 | 
						|
    sg_io_hdr_t io_header;
 | 
						|
    uint8_t sensebuf[8];
 | 
						|
    int ret;
 | 
						|
 | 
						|
    memset(&io_header, 0, sizeof(io_header));
 | 
						|
    io_header.interface_id = 'S';
 | 
						|
    io_header.dxfer_direction = SG_DXFER_FROM_DEV;
 | 
						|
    io_header.dxfer_len = buf_size;
 | 
						|
    io_header.dxferp = buf;
 | 
						|
    io_header.cmdp = cmd;
 | 
						|
    io_header.cmd_len = cmd_size;
 | 
						|
    io_header.mx_sb_len = sizeof(sensebuf);
 | 
						|
    io_header.sbp = sensebuf;
 | 
						|
    io_header.timeout = 6000; /* XXX */
 | 
						|
 | 
						|
    ret = blk_ioctl(blk, SG_IO, &io_header);
 | 
						|
    if (ret < 0 || io_header.driver_status || io_header.host_status) {
 | 
						|
        return -1;
 | 
						|
    }
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * Executes an INQUIRY request with EVPD set to retrieve the
 | 
						|
 * available VPD pages of the device. If the device does
 | 
						|
 * not support the Block Limits page (page 0xb0), set
 | 
						|
 * the needs_vpd_bl_emulation flag for future use.
 | 
						|
 */
 | 
						|
static void scsi_generic_set_vpd_bl_emulation(SCSIDevice *s)
 | 
						|
{
 | 
						|
    uint8_t cmd[6];
 | 
						|
    uint8_t buf[250];
 | 
						|
    uint8_t page_len;
 | 
						|
    int ret, i;
 | 
						|
 | 
						|
    memset(cmd, 0, sizeof(cmd));
 | 
						|
    memset(buf, 0, sizeof(buf));
 | 
						|
    cmd[0] = INQUIRY;
 | 
						|
    cmd[1] = 1;
 | 
						|
    cmd[2] = 0x00;
 | 
						|
    cmd[4] = sizeof(buf);
 | 
						|
 | 
						|
    ret = scsi_SG_IO_FROM_DEV(s->conf.blk, cmd, sizeof(cmd),
 | 
						|
                              buf, sizeof(buf));
 | 
						|
    if (ret < 0) {
 | 
						|
        /*
 | 
						|
         * Do not assume anything if we can't retrieve the
 | 
						|
         * INQUIRY response to assert the VPD Block Limits
 | 
						|
         * support.
 | 
						|
         */
 | 
						|
        s->needs_vpd_bl_emulation = false;
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    page_len = buf[3];
 | 
						|
    for (i = 4; i < MIN(sizeof(buf), page_len + 4); i++) {
 | 
						|
        if (buf[i] == 0xb0) {
 | 
						|
            s->needs_vpd_bl_emulation = false;
 | 
						|
            return;
 | 
						|
        }
 | 
						|
    }
 | 
						|
    s->needs_vpd_bl_emulation = true;
 | 
						|
}
 | 
						|
 | 
						|
static void scsi_generic_read_device_identification(SCSIDevice *s)
 | 
						|
{
 | 
						|
    uint8_t cmd[6];
 | 
						|
    uint8_t buf[250];
 | 
						|
    int ret;
 | 
						|
    int i, len;
 | 
						|
 | 
						|
    memset(cmd, 0, sizeof(cmd));
 | 
						|
    memset(buf, 0, sizeof(buf));
 | 
						|
    cmd[0] = INQUIRY;
 | 
						|
    cmd[1] = 1;
 | 
						|
    cmd[2] = 0x83;
 | 
						|
    cmd[4] = sizeof(buf);
 | 
						|
 | 
						|
    ret = scsi_SG_IO_FROM_DEV(s->conf.blk, cmd, sizeof(cmd),
 | 
						|
                              buf, sizeof(buf));
 | 
						|
    if (ret < 0) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    len = MIN((buf[2] << 8) | buf[3], sizeof(buf) - 4);
 | 
						|
    for (i = 0; i + 3 <= len; ) {
 | 
						|
        const uint8_t *p = &buf[i + 4];
 | 
						|
        uint64_t wwn;
 | 
						|
 | 
						|
        if (i + (p[3] + 4) > len) {
 | 
						|
            break;
 | 
						|
        }
 | 
						|
 | 
						|
        if ((p[1] & 0x10) == 0) {
 | 
						|
            /* Associated with the logical unit */
 | 
						|
            if (read_naa_id(p, &wwn) == 0) {
 | 
						|
                s->wwn = wwn;
 | 
						|
            }
 | 
						|
        } else if ((p[1] & 0x10) == 0x10) {
 | 
						|
            /* Associated with the target port */
 | 
						|
            if (read_naa_id(p, &wwn) == 0) {
 | 
						|
                s->port_wwn = wwn;
 | 
						|
            }
 | 
						|
        }
 | 
						|
 | 
						|
        i += p[3] + 4;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
void scsi_generic_read_device_inquiry(SCSIDevice *s)
 | 
						|
{
 | 
						|
    scsi_generic_read_device_identification(s);
 | 
						|
    if (s->type == TYPE_DISK || s->type == TYPE_ZBC) {
 | 
						|
        scsi_generic_set_vpd_bl_emulation(s);
 | 
						|
    } else {
 | 
						|
        s->needs_vpd_bl_emulation = false;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static int get_stream_blocksize(BlockBackend *blk)
 | 
						|
{
 | 
						|
    uint8_t cmd[6];
 | 
						|
    uint8_t buf[12];
 | 
						|
    int ret;
 | 
						|
 | 
						|
    memset(cmd, 0, sizeof(cmd));
 | 
						|
    memset(buf, 0, sizeof(buf));
 | 
						|
    cmd[0] = MODE_SENSE;
 | 
						|
    cmd[4] = sizeof(buf);
 | 
						|
 | 
						|
    ret = scsi_SG_IO_FROM_DEV(blk, cmd, sizeof(cmd), buf, sizeof(buf));
 | 
						|
    if (ret < 0) {
 | 
						|
        return -1;
 | 
						|
    }
 | 
						|
 | 
						|
    return (buf[9] << 16) | (buf[10] << 8) | buf[11];
 | 
						|
}
 | 
						|
 | 
						|
static void scsi_generic_reset(DeviceState *dev)
 | 
						|
{
 | 
						|
    SCSIDevice *s = SCSI_DEVICE(dev);
 | 
						|
 | 
						|
    s->scsi_version = s->default_scsi_version;
 | 
						|
    scsi_device_purge_requests(s, SENSE_CODE(RESET));
 | 
						|
}
 | 
						|
 | 
						|
static void scsi_generic_realize(SCSIDevice *s, Error **errp)
 | 
						|
{
 | 
						|
    int rc;
 | 
						|
    int sg_version;
 | 
						|
    struct sg_scsi_id scsiid;
 | 
						|
 | 
						|
    if (!s->conf.blk) {
 | 
						|
        error_setg(errp, "drive property not set");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    if (blk_get_on_error(s->conf.blk, 0) != BLOCKDEV_ON_ERROR_ENOSPC) {
 | 
						|
        error_setg(errp, "Device doesn't support drive option werror");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    if (blk_get_on_error(s->conf.blk, 1) != BLOCKDEV_ON_ERROR_REPORT) {
 | 
						|
        error_setg(errp, "Device doesn't support drive option rerror");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /* check we are using a driver managing SG_IO (version 3 and after */
 | 
						|
    rc = blk_ioctl(s->conf.blk, SG_GET_VERSION_NUM, &sg_version);
 | 
						|
    if (rc < 0) {
 | 
						|
        error_setg_errno(errp, -rc, "cannot get SG_IO version number");
 | 
						|
        if (rc != -EPERM) {
 | 
						|
            error_append_hint(errp, "Is this a SCSI device?\n");
 | 
						|
        }
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    if (sg_version < 30000) {
 | 
						|
        error_setg(errp, "scsi generic interface too old");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /* get LUN of the /dev/sg? */
 | 
						|
    if (blk_ioctl(s->conf.blk, SG_GET_SCSI_ID, &scsiid)) {
 | 
						|
        error_setg(errp, "SG_GET_SCSI_ID ioctl failed");
 | 
						|
        return;
 | 
						|
    }
 | 
						|
    if (!blkconf_apply_backend_options(&s->conf,
 | 
						|
                                       !blk_supports_write_perm(s->conf.blk),
 | 
						|
                                       true, errp)) {
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /* define device state */
 | 
						|
    s->type = scsiid.scsi_type;
 | 
						|
    trace_scsi_generic_realize_type(s->type);
 | 
						|
 | 
						|
    switch (s->type) {
 | 
						|
    case TYPE_TAPE:
 | 
						|
        s->blocksize = get_stream_blocksize(s->conf.blk);
 | 
						|
        if (s->blocksize == -1) {
 | 
						|
            s->blocksize = 0;
 | 
						|
        }
 | 
						|
        break;
 | 
						|
 | 
						|
        /* Make a guess for block devices, we'll fix it when the guest sends.
 | 
						|
         * READ CAPACITY.  If they don't, they likely would assume these sizes
 | 
						|
         * anyway. (TODO: they could also send MODE SENSE).
 | 
						|
         */
 | 
						|
    case TYPE_ROM:
 | 
						|
    case TYPE_WORM:
 | 
						|
        s->blocksize = 2048;
 | 
						|
        break;
 | 
						|
    default:
 | 
						|
        s->blocksize = 512;
 | 
						|
        break;
 | 
						|
    }
 | 
						|
 | 
						|
    trace_scsi_generic_realize_blocksize(s->blocksize);
 | 
						|
 | 
						|
    /* Only used by scsi-block, but initialize it nevertheless to be clean.  */
 | 
						|
    s->default_scsi_version = -1;
 | 
						|
    scsi_generic_read_device_inquiry(s);
 | 
						|
}
 | 
						|
 | 
						|
const SCSIReqOps scsi_generic_req_ops = {
 | 
						|
    .size         = sizeof(SCSIGenericReq),
 | 
						|
    .free_req     = scsi_free_request,
 | 
						|
    .send_command = scsi_send_command,
 | 
						|
    .read_data    = scsi_read_data,
 | 
						|
    .write_data   = scsi_write_data,
 | 
						|
    .get_buf      = scsi_get_buf,
 | 
						|
    .load_request = scsi_generic_load_request,
 | 
						|
    .save_request = scsi_generic_save_request,
 | 
						|
};
 | 
						|
 | 
						|
static SCSIRequest *scsi_new_request(SCSIDevice *d, uint32_t tag, uint32_t lun,
 | 
						|
                                     uint8_t *buf, void *hba_private)
 | 
						|
{
 | 
						|
    return scsi_req_alloc(&scsi_generic_req_ops, d, tag, lun, hba_private);
 | 
						|
}
 | 
						|
 | 
						|
static Property scsi_generic_properties[] = {
 | 
						|
    DEFINE_PROP_DRIVE("drive", SCSIDevice, conf.blk),
 | 
						|
    DEFINE_PROP_BOOL("share-rw", SCSIDevice, conf.share_rw, false),
 | 
						|
    DEFINE_PROP_END_OF_LIST(),
 | 
						|
};
 | 
						|
 | 
						|
static int scsi_generic_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
 | 
						|
                                  uint8_t *buf, void *hba_private)
 | 
						|
{
 | 
						|
    return scsi_bus_parse_cdb(dev, cmd, buf, hba_private);
 | 
						|
}
 | 
						|
 | 
						|
static void scsi_generic_class_initfn(ObjectClass *klass, void *data)
 | 
						|
{
 | 
						|
    DeviceClass *dc = DEVICE_CLASS(klass);
 | 
						|
    SCSIDeviceClass *sc = SCSI_DEVICE_CLASS(klass);
 | 
						|
 | 
						|
    sc->realize      = scsi_generic_realize;
 | 
						|
    sc->alloc_req    = scsi_new_request;
 | 
						|
    sc->parse_cdb    = scsi_generic_parse_cdb;
 | 
						|
    dc->fw_name = "disk";
 | 
						|
    dc->desc = "pass through generic scsi device (/dev/sg*)";
 | 
						|
    dc->reset = scsi_generic_reset;
 | 
						|
    device_class_set_props(dc, scsi_generic_properties);
 | 
						|
    dc->vmsd  = &vmstate_scsi_device;
 | 
						|
}
 | 
						|
 | 
						|
static const TypeInfo scsi_generic_info = {
 | 
						|
    .name          = "scsi-generic",
 | 
						|
    .parent        = TYPE_SCSI_DEVICE,
 | 
						|
    .instance_size = sizeof(SCSIDevice),
 | 
						|
    .class_init    = scsi_generic_class_initfn,
 | 
						|
};
 | 
						|
 | 
						|
static void scsi_generic_register_types(void)
 | 
						|
{
 | 
						|
    type_register_static(&scsi_generic_info);
 | 
						|
}
 | 
						|
 | 
						|
type_init(scsi_generic_register_types)
 | 
						|
 | 
						|
#endif /* __linux__ */
 |