diff options
author | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-02-22 18:34:43 -0800 |
---|---|---|
committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-06-02 12:42:07 -0700 |
commit | e31885dd901e80d5bd528c1cbedde07ebbf051b2 (patch) | |
tree | 607777156b57654c5ec44a3a33667fb3938e852a /drivers/vhost/scsi.c | |
parent | b1935f687bb93b207ef690f7debc0e9921fc484f (diff) |
vhost/scsi: Add T10 PI IOV -> SGL memory mapping logic
This patch adds vhost_scsi_map_iov_to_prot() to perform the mapping of
T10 data integrity memory between virtio iov + struct scatterlist using
get_user_pages_fast() following existing code.
As with vhost_scsi_map_iov_to_sgl(), this does sanity checks against the
total prot_sgl_count vs. pre-allocated SGLs, and loops across protection
iovs using vhost_scsi_map_to_sgl() to perform the actual memory mapping.
Also update tcm_vhost_release_cmd() to release associated tvc_prot_sgl[]
struct page.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: H. Peter Anvin <hpa@zytor.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/vhost/scsi.c')
-rw-r--r-- | drivers/vhost/scsi.c | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 30402e618078..eabcf1875831 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -80,6 +80,7 @@ struct tcm_vhost_cmd { u64 tvc_tag; /* The number of scatterlists associated with this cmd */ u32 tvc_sgl_count; + u32 tvc_prot_sgl_count; /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */ u32 tvc_lun; /* Pointer to the SGL formatted memory from virtio-scsi */ @@ -458,12 +459,16 @@ static void tcm_vhost_release_cmd(struct se_cmd *se_cmd) struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, struct tcm_vhost_cmd, tvc_se_cmd); struct se_session *se_sess = se_cmd->se_sess; + int i; if (tv_cmd->tvc_sgl_count) { - u32 i; for (i = 0; i < tv_cmd->tvc_sgl_count; i++) put_page(sg_page(&tv_cmd->tvc_sgl[i])); } + if (tv_cmd->tvc_prot_sgl_count) { + for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); + } tcm_vhost_put_inflight(tv_cmd->inflight); percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag); @@ -861,6 +866,47 @@ vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd, return 0; } +static int +vhost_scsi_map_iov_to_prot(struct tcm_vhost_cmd *cmd, + struct iovec *iov, + int niov, + bool write) +{ + struct scatterlist *prot_sg = cmd->tvc_prot_sgl; + unsigned int prot_sgl_count = 0; + int ret, i; + + for (i = 0; i < niov; i++) + prot_sgl_count += iov_num_pages(&iov[i]); + + if (prot_sgl_count > TCM_VHOST_PREALLOC_PROT_SGLS) { + pr_err("vhost_scsi_map_iov_to_prot() sgl_count: %u greater than" + " preallocated TCM_VHOST_PREALLOC_PROT_SGLS: %u\n", + prot_sgl_count, TCM_VHOST_PREALLOC_PROT_SGLS); + return -ENOBUFS; + } + + pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__, + prot_sg, prot_sgl_count); + sg_init_table(prot_sg, prot_sgl_count); + cmd->tvc_prot_sgl_count = prot_sgl_count; + + for (i = 0; i < niov; i++) { + ret = vhost_scsi_map_to_sgl(cmd, prot_sg, prot_sgl_count, &iov[i], + cmd->tvc_upages, write); + if (ret < 0) { + for (i = 0; i < cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&cmd->tvc_prot_sgl[i])); + + cmd->tvc_prot_sgl_count = 0; + return ret; + } + prot_sg += ret; + prot_sgl_count -= ret; + } + return 0; +} + static void tcm_vhost_submission_work(struct work_struct *work) { struct tcm_vhost_cmd *cmd = |