tcm_vhost: Initial merge for vhost level target fabric driver

This patch adds the initial code for tcm_vhost, a Vhost level TCM
fabric driver for virtio SCSI initiators into KVM guest.

This code is currently up and running on v3.5-rc2 host+guest
from target-pending/for-next-merge.

Using tcm_vhost requires Zhi's -> Stefan -> nab's qemu vhost-scsi tree here:

  http://git.kernel.org/?p=virt/kvm/nab/qemu-kvm.git;a=shortlog;h=refs/heads/vhost-scsi

--

Changelog v4 -> v5:

  Expose ABI version via VHOST_SCSI_GET_ABI_VERSION + use Rev 0 as
  starting point for v3.6-rc code (Stefan + ALiguori + nab)
  Convert vhost_scsi_handle_vq() to vq_err() (nab + MST)
  Minor style fixes from checkpatch (nab)

Changelog v3 -> v4:

  Rename vhost_vring_target -> vhost_scsi_target (mst + nab)
  Use TRANSPORT_IQN_LEN in vhost_scsi_target->vhost_wwpn[] def (nab)
  Move back to drivers/vhost/, and just use drivers/vhost/Kconfig.tcm (mst)
  Move TCM_VHOST related ioctl defines from include/linux/vhost.h ->
  drivers/vhost/tcm_vhost.h as requested by MST (nab)
  Move Kbuild.tcm include from drivers/staging -> drivers/vhost/, and
  just use 'if STAGING' around 'source drivers/vhost/Kbuild.tcm'

Changelog v2 -> v3:

  Unlock on error in tcm_vhost_drop_nexus() (DanC)
  Fix strlen() doesn't count the terminator (DanC)
  Call kfree() on an error path (DanC)
  Convert tcm_vhost_write_pending to use target_execute_cmd (hch + nab)
  Fix another strlen() off by one in tcm_vhost_make_tport (DanC)
  Add option under drivers/staging/Kconfig, and move to drivers/vhost/tcm/
  as requested by MST (nab)

Changelog v1 -> v2:

  Fix tv_cmd completion -> release SGL memory leak (nab)
  Fix sparse warnings for static variable usage ((Fengguang Wu)
  Fix sparse warnings for min() typing + printk format specs (Fengguang Wu)
  Convert to cmwq submission for I/O dispatch (nab + hch)

Changelog v0 -> v1:

  Merge into single source + header file, and move to drivers/vhost/

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2012-07-18 14:31:32 -07:00
parent bdc0077af5
commit 057cbf49a1
5 changed files with 1740 additions and 0 deletions

View File

@ -9,3 +9,6 @@ config VHOST_NET
To compile this driver as a module, choose M here: the module will
be called vhost_net.
if STAGING
source "drivers/vhost/Kconfig.tcm"
endif

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@ -0,0 +1,6 @@
config TCM_VHOST
tristate "TCM_VHOST fabric module (EXPERIMENTAL)"
depends on TARGET_CORE && EVENTFD && EXPERIMENTAL && m
default n
---help---
Say M here to enable the TCM_VHOST fabric module for use with virtio-scsi guests

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@ -1,2 +1,4 @@
obj-$(CONFIG_VHOST_NET) += vhost_net.o
vhost_net-y := vhost.o net.o
obj-$(CONFIG_TCM_VHOST) += tcm_vhost.o

1628
drivers/vhost/tcm_vhost.c Normal file

File diff suppressed because it is too large Load Diff

101
drivers/vhost/tcm_vhost.h Normal file
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@ -0,0 +1,101 @@
#define TCM_VHOST_VERSION "v0.1"
#define TCM_VHOST_NAMELEN 256
#define TCM_VHOST_MAX_CDB_SIZE 32
struct tcm_vhost_cmd {
/* Descriptor from vhost_get_vq_desc() for virt_queue segment */
int tvc_vq_desc;
/* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
u64 tvc_tag;
/* The number of scatterlists associated with this cmd */
u32 tvc_sgl_count;
/* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
u32 tvc_lun;
/* Pointer to the SGL formatted memory from virtio-scsi */
struct scatterlist *tvc_sgl;
/* Pointer to response */
struct virtio_scsi_cmd_resp __user *tvc_resp;
/* Pointer to vhost_scsi for our device */
struct vhost_scsi *tvc_vhost;
/* The TCM I/O descriptor that is accessed via container_of() */
struct se_cmd tvc_se_cmd;
/* work item used for cmwq dispatch to tcm_vhost_submission_work() */
struct work_struct work;
/* Copy of the incoming SCSI command descriptor block (CDB) */
unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
/* Sense buffer that will be mapped into outgoing status */
unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
/* Completed commands list, serviced from vhost worker thread */
struct list_head tvc_completion_list;
};
struct tcm_vhost_nexus {
/* Pointer to TCM session for I_T Nexus */
struct se_session *tvn_se_sess;
};
struct tcm_vhost_nacl {
/* Binary World Wide unique Port Name for Vhost Initiator port */
u64 iport_wwpn;
/* ASCII formatted WWPN for Sas Initiator port */
char iport_name[TCM_VHOST_NAMELEN];
/* Returned by tcm_vhost_make_nodeacl() */
struct se_node_acl se_node_acl;
};
struct tcm_vhost_tpg {
/* Vhost port target portal group tag for TCM */
u16 tport_tpgt;
/* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
atomic_t tv_tpg_port_count;
/* Used for vhost_scsi device reference to tpg_nexus */
atomic_t tv_tpg_vhost_count;
/* list for tcm_vhost_list */
struct list_head tv_tpg_list;
/* Used to protect access for tpg_nexus */
struct mutex tv_tpg_mutex;
/* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
struct tcm_vhost_nexus *tpg_nexus;
/* Pointer back to tcm_vhost_tport */
struct tcm_vhost_tport *tport;
/* Returned by tcm_vhost_make_tpg() */
struct se_portal_group se_tpg;
};
struct tcm_vhost_tport {
/* SCSI protocol the tport is providing */
u8 tport_proto_id;
/* Binary World Wide unique Port Name for Vhost Target port */
u64 tport_wwpn;
/* ASCII formatted WWPN for Vhost Target port */
char tport_name[TCM_VHOST_NAMELEN];
/* Returned by tcm_vhost_make_tport() */
struct se_wwn tport_wwn;
};
/*
* As per request from MST, keep TCM_VHOST related ioctl defines out of
* linux/vhost.h (user-space) for now..
*/
#include <linux/vhost.h>
/*
* Used by QEMU userspace to ensure a consistent vhost-scsi ABI.
*
* ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate +
* RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage
*/
#define VHOST_SCSI_ABI_VERSION 0
struct vhost_scsi_target {
int abi_version;
unsigned char vhost_wwpn[TRANSPORT_IQN_LEN];
unsigned short vhost_tpgt;
};
/* VHOST_SCSI specific defines */
#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, struct vhost_scsi_target)