RDMA/uverbs: Export XRC domains to user space
Allow user space to create XRC domains. Because XRCDs are expected to
be shared among multiple processes, we use inodes to identify an XRCD.
Based on patches by Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index a078e56..461e2f3 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -76,6 +76,8 @@
struct ib_device *ib_dev;
int devnum;
struct cdev cdev;
+ struct rb_root xrcd_tree;
+ struct mutex xrcd_tree_mutex;
};
struct ib_uverbs_event_file {
@@ -120,6 +122,11 @@
u32 events_reported;
};
+struct ib_uxrcd_object {
+ struct ib_uobject uobject;
+ atomic_t refcnt;
+};
+
struct ib_uqp_object {
struct ib_uevent_object uevent;
struct list_head mcast_list;
@@ -142,6 +149,7 @@
extern struct idr ib_uverbs_cq_idr;
extern struct idr ib_uverbs_qp_idr;
extern struct idr ib_uverbs_srq_idr;
+extern struct idr ib_uverbs_xrcd_idr;
void idr_remove_uobj(struct idr *idp, struct ib_uobject *uobj);
@@ -161,6 +169,7 @@
void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr);
void ib_uverbs_event_handler(struct ib_event_handler *handler,
struct ib_event *event);
+void ib_uverbs_dealloc_xrcd(struct ib_uverbs_device *dev, struct ib_xrcd *xrcd);
#define IB_UVERBS_DECLARE_CMD(name) \
ssize_t ib_uverbs_##name(struct ib_uverbs_file *file, \
@@ -195,5 +204,7 @@
IB_UVERBS_DECLARE_CMD(modify_srq);
IB_UVERBS_DECLARE_CMD(query_srq);
IB_UVERBS_DECLARE_CMD(destroy_srq);
+IB_UVERBS_DECLARE_CMD(open_xrcd);
+IB_UVERBS_DECLARE_CMD(close_xrcd);
#endif /* UVERBS_H */
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 48d21d0..c8b2a84 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -47,6 +47,7 @@
static struct lock_class_key qp_lock_key;
static struct lock_class_key ah_lock_key;
static struct lock_class_key srq_lock_key;
+static struct lock_class_key xrcd_lock_key;
#define INIT_UDATA(udata, ibuf, obuf, ilen, olen) \
do { \
@@ -255,6 +256,18 @@
put_uobj_read(srq->uobject);
}
+static struct ib_xrcd *idr_read_xrcd(int xrcd_handle, struct ib_ucontext *context,
+ struct ib_uobject **uobj)
+{
+ *uobj = idr_read_uobj(&ib_uverbs_xrcd_idr, xrcd_handle, context, 0);
+ return *uobj ? (*uobj)->object : NULL;
+}
+
+static void put_xrcd_read(struct ib_uobject *uobj)
+{
+ put_uobj_read(uobj);
+}
+
ssize_t ib_uverbs_get_context(struct ib_uverbs_file *file,
const char __user *buf,
int in_len, int out_len)
@@ -298,6 +311,7 @@
INIT_LIST_HEAD(&ucontext->qp_list);
INIT_LIST_HEAD(&ucontext->srq_list);
INIT_LIST_HEAD(&ucontext->ah_list);
+ INIT_LIST_HEAD(&ucontext->xrcd_list);
ucontext->closing = 0;
resp.num_comp_vectors = file->device->num_comp_vectors;
@@ -579,6 +593,310 @@
return in_len;
}
+struct xrcd_table_entry {
+ struct rb_node node;
+ struct ib_xrcd *xrcd;
+ struct inode *inode;
+};
+
+static int xrcd_table_insert(struct ib_uverbs_device *dev,
+ struct inode *inode,
+ struct ib_xrcd *xrcd)
+{
+ struct xrcd_table_entry *entry, *scan;
+ struct rb_node **p = &dev->xrcd_tree.rb_node;
+ struct rb_node *parent = NULL;
+
+ entry = kmalloc(sizeof *entry, GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->xrcd = xrcd;
+ entry->inode = inode;
+
+ while (*p) {
+ parent = *p;
+ scan = rb_entry(parent, struct xrcd_table_entry, node);
+
+ if (inode < scan->inode) {
+ p = &(*p)->rb_left;
+ } else if (inode > scan->inode) {
+ p = &(*p)->rb_right;
+ } else {
+ kfree(entry);
+ return -EEXIST;
+ }
+ }
+
+ rb_link_node(&entry->node, parent, p);
+ rb_insert_color(&entry->node, &dev->xrcd_tree);
+ igrab(inode);
+ return 0;
+}
+
+static struct xrcd_table_entry *xrcd_table_search(struct ib_uverbs_device *dev,
+ struct inode *inode)
+{
+ struct xrcd_table_entry *entry;
+ struct rb_node *p = dev->xrcd_tree.rb_node;
+
+ while (p) {
+ entry = rb_entry(p, struct xrcd_table_entry, node);
+
+ if (inode < entry->inode)
+ p = p->rb_left;
+ else if (inode > entry->inode)
+ p = p->rb_right;
+ else
+ return entry;
+ }
+
+ return NULL;
+}
+
+static struct ib_xrcd *find_xrcd(struct ib_uverbs_device *dev, struct inode *inode)
+{
+ struct xrcd_table_entry *entry;
+
+ entry = xrcd_table_search(dev, inode);
+ if (!entry)
+ return NULL;
+
+ return entry->xrcd;
+}
+
+static void xrcd_table_delete(struct ib_uverbs_device *dev,
+ struct inode *inode)
+{
+ struct xrcd_table_entry *entry;
+
+ entry = xrcd_table_search(dev, inode);
+ if (entry) {
+ iput(inode);
+ rb_erase(&entry->node, &dev->xrcd_tree);
+ kfree(entry);
+ }
+}
+
+ssize_t ib_uverbs_open_xrcd(struct ib_uverbs_file *file,
+ const char __user *buf, int in_len,
+ int out_len)
+{
+ struct ib_uverbs_open_xrcd cmd;
+ struct ib_uverbs_open_xrcd_resp resp;
+ struct ib_udata udata;
+ struct ib_uxrcd_object *obj;
+ struct ib_xrcd *xrcd = NULL;
+ struct file *f = NULL;
+ struct inode *inode = NULL;
+ int ret = 0;
+ int new_xrcd = 0;
+
+ 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);
+
+ mutex_lock(&file->device->xrcd_tree_mutex);
+
+ if (cmd.fd != -1) {
+ /* search for file descriptor */
+ f = fget(cmd.fd);
+ if (!f) {
+ ret = -EBADF;
+ goto err_tree_mutex_unlock;
+ }
+
+ inode = f->f_dentry->d_inode;
+ if (!inode) {
+ ret = -EBADF;
+ goto err_tree_mutex_unlock;
+ }
+
+ xrcd = find_xrcd(file->device, inode);
+ if (!xrcd && !(cmd.oflags & O_CREAT)) {
+ /* no file descriptor. Need CREATE flag */
+ ret = -EAGAIN;
+ goto err_tree_mutex_unlock;
+ }
+
+ if (xrcd && cmd.oflags & O_EXCL) {
+ ret = -EINVAL;
+ goto err_tree_mutex_unlock;
+ }
+ }
+
+ obj = kmalloc(sizeof *obj, GFP_KERNEL);
+ if (!obj) {
+ ret = -ENOMEM;
+ goto err_tree_mutex_unlock;
+ }
+
+ init_uobj(&obj->uobject, 0, file->ucontext, &xrcd_lock_key);
+
+ down_write(&obj->uobject.mutex);
+
+ if (!xrcd) {
+ xrcd = file->device->ib_dev->alloc_xrcd(file->device->ib_dev,
+ file->ucontext, &udata);
+ if (IS_ERR(xrcd)) {
+ ret = PTR_ERR(xrcd);
+ goto err;
+ }
+
+ xrcd->inode = inode;
+ xrcd->device = file->device->ib_dev;
+ atomic_set(&xrcd->usecnt, 0);
+ mutex_init(&xrcd->tgt_qp_mutex);
+ INIT_LIST_HEAD(&xrcd->tgt_qp_list);
+ new_xrcd = 1;
+ }
+
+ atomic_set(&obj->refcnt, 0);
+ obj->uobject.object = xrcd;
+ ret = idr_add_uobj(&ib_uverbs_xrcd_idr, &obj->uobject);
+ if (ret)
+ goto err_idr;
+
+ memset(&resp, 0, sizeof resp);
+ resp.xrcd_handle = obj->uobject.id;
+
+ if (inode) {
+ if (new_xrcd) {
+ /* create new inode/xrcd table entry */
+ ret = xrcd_table_insert(file->device, inode, xrcd);
+ if (ret)
+ goto err_insert_xrcd;
+ }
+ atomic_inc(&xrcd->usecnt);
+ }
+
+ if (copy_to_user((void __user *) (unsigned long) cmd.response,
+ &resp, sizeof resp)) {
+ ret = -EFAULT;
+ goto err_copy;
+ }
+
+ if (f)
+ fput(f);
+
+ mutex_lock(&file->mutex);
+ list_add_tail(&obj->uobject.list, &file->ucontext->xrcd_list);
+ mutex_unlock(&file->mutex);
+
+ obj->uobject.live = 1;
+ up_write(&obj->uobject.mutex);
+
+ mutex_unlock(&file->device->xrcd_tree_mutex);
+ return in_len;
+
+err_copy:
+ if (inode) {
+ if (new_xrcd)
+ xrcd_table_delete(file->device, inode);
+ atomic_dec(&xrcd->usecnt);
+ }
+
+err_insert_xrcd:
+ idr_remove_uobj(&ib_uverbs_xrcd_idr, &obj->uobject);
+
+err_idr:
+ ib_dealloc_xrcd(xrcd);
+
+err:
+ put_uobj_write(&obj->uobject);
+
+err_tree_mutex_unlock:
+ if (f)
+ fput(f);
+
+ mutex_unlock(&file->device->xrcd_tree_mutex);
+
+ return ret;
+}
+
+ssize_t ib_uverbs_close_xrcd(struct ib_uverbs_file *file,
+ const char __user *buf, int in_len,
+ int out_len)
+{
+ struct ib_uverbs_close_xrcd cmd;
+ struct ib_uobject *uobj;
+ struct ib_xrcd *xrcd = NULL;
+ struct inode *inode = NULL;
+ struct ib_uxrcd_object *obj;
+ int live;
+ int ret = 0;
+
+ if (copy_from_user(&cmd, buf, sizeof cmd))
+ return -EFAULT;
+
+ mutex_lock(&file->device->xrcd_tree_mutex);
+ uobj = idr_write_uobj(&ib_uverbs_xrcd_idr, cmd.xrcd_handle, file->ucontext);
+ if (!uobj) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ xrcd = uobj->object;
+ inode = xrcd->inode;
+ obj = container_of(uobj, struct ib_uxrcd_object, uobject);
+ if (atomic_read(&obj->refcnt)) {
+ put_uobj_write(uobj);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ if (!inode || atomic_dec_and_test(&xrcd->usecnt)) {
+ ret = ib_dealloc_xrcd(uobj->object);
+ if (!ret)
+ uobj->live = 0;
+ }
+
+ live = uobj->live;
+ if (inode && ret)
+ atomic_inc(&xrcd->usecnt);
+
+ put_uobj_write(uobj);
+
+ if (ret)
+ goto out;
+
+ if (inode && !live)
+ xrcd_table_delete(file->device, inode);
+
+ idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
+ mutex_lock(&file->mutex);
+ list_del(&uobj->list);
+ mutex_unlock(&file->mutex);
+
+ put_uobj(uobj);
+ ret = in_len;
+
+out:
+ mutex_unlock(&file->device->xrcd_tree_mutex);
+ return ret;
+}
+
+void ib_uverbs_dealloc_xrcd(struct ib_uverbs_device *dev,
+ struct ib_xrcd *xrcd)
+{
+ struct inode *inode;
+
+ inode = xrcd->inode;
+ if (inode && !atomic_dec_and_test(&xrcd->usecnt))
+ return;
+
+ ib_dealloc_xrcd(xrcd);
+
+ if (inode)
+ xrcd_table_delete(dev, inode);
+}
+
ssize_t ib_uverbs_reg_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 56898b6..bb9dcea 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -72,6 +72,7 @@
DEFINE_IDR(ib_uverbs_cq_idr);
DEFINE_IDR(ib_uverbs_qp_idr);
DEFINE_IDR(ib_uverbs_srq_idr);
+DEFINE_IDR(ib_uverbs_xrcd_idr);
static DEFINE_SPINLOCK(map_lock);
static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
@@ -107,6 +108,8 @@
[IB_USER_VERBS_CMD_MODIFY_SRQ] = ib_uverbs_modify_srq,
[IB_USER_VERBS_CMD_QUERY_SRQ] = ib_uverbs_query_srq,
[IB_USER_VERBS_CMD_DESTROY_SRQ] = ib_uverbs_destroy_srq,
+ [IB_USER_VERBS_CMD_OPEN_XRCD] = ib_uverbs_open_xrcd,
+ [IB_USER_VERBS_CMD_CLOSE_XRCD] = ib_uverbs_close_xrcd,
};
static void ib_uverbs_add_one(struct ib_device *device);
@@ -241,6 +244,18 @@
kfree(uobj);
}
+ mutex_lock(&file->device->xrcd_tree_mutex);
+ list_for_each_entry_safe(uobj, tmp, &context->xrcd_list, list) {
+ struct ib_xrcd *xrcd = uobj->object;
+ struct ib_uxrcd_object *uxrcd =
+ container_of(uobj, struct ib_uxrcd_object, uobject);
+
+ idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
+ ib_uverbs_dealloc_xrcd(file->device, xrcd);
+ kfree(uxrcd);
+ }
+ mutex_unlock(&file->device->xrcd_tree_mutex);
+
list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
struct ib_pd *pd = uobj->object;
@@ -741,6 +756,8 @@
kref_init(&uverbs_dev->ref);
init_completion(&uverbs_dev->comp);
+ uverbs_dev->xrcd_tree = RB_ROOT;
+ mutex_init(&uverbs_dev->xrcd_tree_mutex);
spin_lock(&map_lock);
devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 8c6da5b..a6d95e6 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1096,6 +1096,7 @@
xrcd = device->alloc_xrcd(device, NULL, NULL);
if (!IS_ERR(xrcd)) {
xrcd->device = device;
+ xrcd->inode = NULL;
atomic_set(&xrcd->usecnt, 0);
mutex_init(&xrcd->tgt_qp_mutex);
INIT_LIST_HEAD(&xrcd->tgt_qp_list);
diff --git a/include/rdma/ib_user_verbs.h b/include/rdma/ib_user_verbs.h
index fe5b051..b5cb63f 100644
--- a/include/rdma/ib_user_verbs.h
+++ b/include/rdma/ib_user_verbs.h
@@ -81,7 +81,9 @@
IB_USER_VERBS_CMD_MODIFY_SRQ,
IB_USER_VERBS_CMD_QUERY_SRQ,
IB_USER_VERBS_CMD_DESTROY_SRQ,
- IB_USER_VERBS_CMD_POST_SRQ_RECV
+ IB_USER_VERBS_CMD_POST_SRQ_RECV,
+ IB_USER_VERBS_CMD_OPEN_XRCD,
+ IB_USER_VERBS_CMD_CLOSE_XRCD
};
/*
@@ -222,6 +224,21 @@
__u32 pd_handle;
};
+struct ib_uverbs_open_xrcd {
+ __u64 response;
+ __u32 fd;
+ __u32 oflags;
+ __u64 driver_data[0];
+};
+
+struct ib_uverbs_open_xrcd_resp {
+ __u32 xrcd_handle;
+};
+
+struct ib_uverbs_close_xrcd {
+ __u32 xrcd_handle;
+};
+
struct ib_uverbs_reg_mr {
__u64 response;
__u64 start;
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index ac46dcf..dfd9b87 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -851,6 +851,7 @@
struct list_head qp_list;
struct list_head srq_list;
struct list_head ah_list;
+ struct list_head xrcd_list;
int closing;
};
@@ -881,6 +882,7 @@
struct ib_xrcd {
struct ib_device *device;
atomic_t usecnt; /* count all exposed resources */
+ struct inode *inode;
struct mutex tgt_qp_mutex;
struct list_head tgt_qp_list;