IB/core: Add user MR re-registration support
Memory re-registration is a feature that enables changing the
attributes of a memory region registered by user-space, including PD,
translation (address and length) and access flags.
Add the required support in uverbs and the kernel verbs API.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index a283274..643c08a 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -221,6 +221,7 @@
IB_UVERBS_DECLARE_CMD(alloc_pd);
IB_UVERBS_DECLARE_CMD(dealloc_pd);
IB_UVERBS_DECLARE_CMD(reg_mr);
+IB_UVERBS_DECLARE_CMD(rereg_mr);
IB_UVERBS_DECLARE_CMD(dereg_mr);
IB_UVERBS_DECLARE_CMD(alloc_mw);
IB_UVERBS_DECLARE_CMD(dealloc_mw);
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index ea6203e..0600c50 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1002,6 +1002,99 @@
return ret;
}
+ssize_t ib_uverbs_rereg_mr(struct ib_uverbs_file *file,
+ const char __user *buf, int in_len,
+ int out_len)
+{
+ struct ib_uverbs_rereg_mr cmd;
+ struct ib_uverbs_rereg_mr_resp resp;
+ struct ib_udata udata;
+ struct ib_pd *pd = NULL;
+ struct ib_mr *mr;
+ struct ib_pd *old_pd;
+ int ret;
+ struct ib_uobject *uobj;
+
+ if (out_len < sizeof(resp))
+ return -ENOSPC;
+
+ if (copy_from_user(&cmd, buf, sizeof(cmd)))
+ return -EFAULT;
+
+ INIT_UDATA(&udata, buf + sizeof(cmd),
+ (unsigned long) cmd.response + sizeof(resp),
+ in_len - sizeof(cmd), out_len - sizeof(resp));
+
+ if (cmd.flags & ~IB_MR_REREG_SUPPORTED || !cmd.flags)
+ return -EINVAL;
+
+ if ((cmd.flags & IB_MR_REREG_TRANS) &&
+ (!cmd.start || !cmd.hca_va || 0 >= cmd.length ||
+ (cmd.start & ~PAGE_MASK) != (cmd.hca_va & ~PAGE_MASK)))
+ return -EINVAL;
+
+ uobj = idr_write_uobj(&ib_uverbs_mr_idr, cmd.mr_handle,
+ file->ucontext);
+
+ if (!uobj)
+ return -EINVAL;
+
+ mr = uobj->object;
+
+ if (cmd.flags & IB_MR_REREG_ACCESS) {
+ ret = ib_check_mr_access(cmd.access_flags);
+ if (ret)
+ goto put_uobjs;
+ }
+
+ if (cmd.flags & IB_MR_REREG_PD) {
+ pd = idr_read_pd(cmd.pd_handle, file->ucontext);
+ if (!pd) {
+ ret = -EINVAL;
+ goto put_uobjs;
+ }
+ }
+
+ if (atomic_read(&mr->usecnt)) {
+ ret = -EBUSY;
+ goto put_uobj_pd;
+ }
+
+ old_pd = mr->pd;
+ ret = mr->device->rereg_user_mr(mr, cmd.flags, cmd.start,
+ cmd.length, cmd.hca_va,
+ cmd.access_flags, pd, &udata);
+ if (!ret) {
+ if (cmd.flags & IB_MR_REREG_PD) {
+ atomic_inc(&pd->usecnt);
+ mr->pd = pd;
+ atomic_dec(&old_pd->usecnt);
+ }
+ } else {
+ goto put_uobj_pd;
+ }
+
+ memset(&resp, 0, sizeof(resp));
+ resp.lkey = mr->lkey;
+ resp.rkey = mr->rkey;
+
+ if (copy_to_user((void __user *)(unsigned long)cmd.response,
+ &resp, sizeof(resp)))
+ ret = -EFAULT;
+ else
+ ret = in_len;
+
+put_uobj_pd:
+ if (cmd.flags & IB_MR_REREG_PD)
+ put_pd_read(pd);
+
+put_uobjs:
+
+ put_uobj_write(mr->uobject);
+
+ return ret;
+}
+
ssize_t ib_uverbs_dereg_mr(struct ib_uverbs_file *file,
const char __user *buf, int in_len,
int out_len)
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 08219fb..c73b22a 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -87,6 +87,7 @@
[IB_USER_VERBS_CMD_ALLOC_PD] = ib_uverbs_alloc_pd,
[IB_USER_VERBS_CMD_DEALLOC_PD] = ib_uverbs_dealloc_pd,
[IB_USER_VERBS_CMD_REG_MR] = ib_uverbs_reg_mr,
+ [IB_USER_VERBS_CMD_REREG_MR] = ib_uverbs_rereg_mr,
[IB_USER_VERBS_CMD_DEREG_MR] = ib_uverbs_dereg_mr,
[IB_USER_VERBS_CMD_ALLOC_MW] = ib_uverbs_alloc_mw,
[IB_USER_VERBS_CMD_DEALLOC_MW] = ib_uverbs_dealloc_mw,
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 7ccef34..ed44cc0 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1097,7 +1097,8 @@
enum ib_mr_rereg_flags {
IB_MR_REREG_TRANS = 1,
IB_MR_REREG_PD = (1<<1),
- IB_MR_REREG_ACCESS = (1<<2)
+ IB_MR_REREG_ACCESS = (1<<2),
+ IB_MR_REREG_SUPPORTED = ((IB_MR_REREG_ACCESS << 1) - 1)
};
/**
@@ -1547,6 +1548,13 @@
u64 virt_addr,
int mr_access_flags,
struct ib_udata *udata);
+ int (*rereg_user_mr)(struct ib_mr *mr,
+ int flags,
+ u64 start, u64 length,
+ u64 virt_addr,
+ int mr_access_flags,
+ struct ib_pd *pd,
+ struct ib_udata *udata);
int (*query_mr)(struct ib_mr *mr,
struct ib_mr_attr *mr_attr);
int (*dereg_mr)(struct ib_mr *mr);
diff --git a/include/uapi/rdma/ib_user_verbs.h b/include/uapi/rdma/ib_user_verbs.h
index cbfdd4c..26daf55 100644
--- a/include/uapi/rdma/ib_user_verbs.h
+++ b/include/uapi/rdma/ib_user_verbs.h
@@ -276,6 +276,22 @@
__u32 rkey;
};
+struct ib_uverbs_rereg_mr {
+ __u64 response;
+ __u32 mr_handle;
+ __u32 flags;
+ __u64 start;
+ __u64 length;
+ __u64 hca_va;
+ __u32 pd_handle;
+ __u32 access_flags;
+};
+
+struct ib_uverbs_rereg_mr_resp {
+ __u32 lkey;
+ __u32 rkey;
+};
+
struct ib_uverbs_dereg_mr {
__u32 mr_handle;
};