rdma_core.c | Explore in Territory

/*
 * Copyright (c) 2016, Mellanox Technologies inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/file.h>
#include <linux/anon_inodes.h>
#include <linux/sched/mm.h>
#include <rdma/ib_verbs.h>
#include <rdma/uverbs_types.h>
#include <linux/rcupdate.h>
#include <rdma/uverbs_ioctl.h>
#include <rdma/rdma_user_ioctl.h>
#include "uverbs.h"
#include "core_priv.h"
#include "rdma_core.h"

static void uverbs_uobject_free(struct kref *ref)
{ … }

/*
 * In order to indicate we no longer needs this uobject, uverbs_uobject_put
 * is called. When the reference count is decreased, the uobject is freed.
 * For example, this is used when attaching a completion channel to a CQ.
 */
void uverbs_uobject_put(struct ib_uobject *uobject)
{ … }
EXPORT_SYMBOL(…);

static int uverbs_try_lock_object(struct ib_uobject *uobj,
				  enum rdma_lookup_mode mode)
{ … }

static void assert_uverbs_usecnt(struct ib_uobject *uobj,
				 enum rdma_lookup_mode mode)
{ … }

/*
 * This must be called with the hw_destroy_rwsem locked for read or write,
 * also the uobject itself must be locked for write.
 *
 * Upon return the HW object is guaranteed to be destroyed.
 *
 * For RDMA_REMOVE_ABORT, the hw_destroy_rwsem is not required to be held,
 * however the type's allocat_commit function cannot have been called and the
 * uobject cannot be on the uobjects_lists
 *
 * For RDMA_REMOVE_DESTROY the caller should be holding a kref (eg via
 * rdma_lookup_get_uobject) and the object is left in a state where the caller
 * needs to call rdma_lookup_put_uobject.
 *
 * For all other destroy modes this function internally unlocks the uobject
 * and consumes the kref on the uobj.
 */
static int uverbs_destroy_uobject(struct ib_uobject *uobj,
				  enum rdma_remove_reason reason,
				  struct uverbs_attr_bundle *attrs)
{ … }

/*
 * This calls uverbs_destroy_uobject() using the RDMA_REMOVE_DESTROY
 * sequence. It should only be used from command callbacks. On success the
 * caller must pair this with uobj_put_destroy(). This
 * version requires the caller to have already obtained an
 * LOOKUP_DESTROY uobject kref.
 */
int uobj_destroy(struct ib_uobject *uobj, struct uverbs_attr_bundle *attrs)
{ … }

/*
 * uobj_get_destroy destroys the HW object and returns a handle to the uobj
 * with a NULL object pointer. The caller must pair this with
 * uobj_put_destroy().
 */
struct ib_uobject *__uobj_get_destroy(const struct uverbs_api_object *obj,
				      u32 id, struct uverbs_attr_bundle *attrs)
{ … }

/*
 * Does both uobj_get_destroy() and uobj_put_destroy().  Returns 0 on success
 * (negative errno on failure). For use by callers that do not need the uobj.
 */
int __uobj_perform_destroy(const struct uverbs_api_object *obj, u32 id,
			   struct uverbs_attr_bundle *attrs)
{ … }

/* alloc_uobj must be undone by uverbs_destroy_uobject() */
static struct ib_uobject *alloc_uobj(struct uverbs_attr_bundle *attrs,
				     const struct uverbs_api_object *obj)
{ … }

static int idr_add_uobj(struct ib_uobject *uobj)
{ … }

/* Returns the ib_uobject or an error. The caller should check for IS_ERR. */
static struct ib_uobject *
lookup_get_idr_uobject(const struct uverbs_api_object *obj,
		       struct ib_uverbs_file *ufile, s64 id,
		       enum rdma_lookup_mode mode)
{ … }

static struct ib_uobject *
lookup_get_fd_uobject(const struct uverbs_api_object *obj,
		      struct ib_uverbs_file *ufile, s64 id,
		      enum rdma_lookup_mode mode)
{ … }

struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_api_object *obj,
					   struct ib_uverbs_file *ufile, s64 id,
					   enum rdma_lookup_mode mode,
					   struct uverbs_attr_bundle *attrs)
{ … }

static struct ib_uobject *
alloc_begin_idr_uobject(const struct uverbs_api_object *obj,
			struct uverbs_attr_bundle *attrs)
{ … }

static struct ib_uobject *
alloc_begin_fd_uobject(const struct uverbs_api_object *obj,
		       struct uverbs_attr_bundle *attrs)
{ … }

struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj,
					    struct uverbs_attr_bundle *attrs)
{ … }

static void alloc_abort_idr_uobject(struct ib_uobject *uobj)
{ … }

static int __must_check destroy_hw_idr_uobject(struct ib_uobject *uobj,
					       enum rdma_remove_reason why,
					       struct uverbs_attr_bundle *attrs)
{ … }

static void remove_handle_idr_uobject(struct ib_uobject *uobj)
{ … }

static void alloc_abort_fd_uobject(struct ib_uobject *uobj)
{ … }

static int __must_check destroy_hw_fd_uobject(struct ib_uobject *uobj,
					      enum rdma_remove_reason why,
					      struct uverbs_attr_bundle *attrs)
{ … }

static void remove_handle_fd_uobject(struct ib_uobject *uobj)
{ … }

static void alloc_commit_idr_uobject(struct ib_uobject *uobj)
{ … }

static void swap_idr_uobjects(struct ib_uobject *obj_old,
			     struct ib_uobject *obj_new)
{ … }

static void alloc_commit_fd_uobject(struct ib_uobject *uobj)
{ … }

/*
 * In all cases rdma_alloc_commit_uobject() consumes the kref to uobj and the
 * caller can no longer assume uobj is valid. If this function fails it
 * destroys the uboject, including the attached HW object.
 */
void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
			       struct uverbs_attr_bundle *attrs)
{ … }

/*
 * new_uobj will be assigned to the handle currently used by to_uobj, and
 * to_uobj will be destroyed.
 *
 * Upon return the caller must do:
 *    rdma_alloc_commit_uobject(new_uobj)
 *    uobj_put_destroy(to_uobj)
 *
 * to_uobj must have a write get but the put mode switches to destroy once
 * this is called.
 */
void rdma_assign_uobject(struct ib_uobject *to_uobj, struct ib_uobject *new_uobj,
			struct uverbs_attr_bundle *attrs)
{ … }

/*
 * This consumes the kref for uobj. It is up to the caller to unwind the HW
 * object and anything else connected to uobj before calling this.
 */
void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
			      struct uverbs_attr_bundle *attrs,
			      bool hw_obj_valid)
{ … }

static void lookup_put_idr_uobject(struct ib_uobject *uobj,
				   enum rdma_lookup_mode mode)
{ … }

static void lookup_put_fd_uobject(struct ib_uobject *uobj,
				  enum rdma_lookup_mode mode)
{ … }

void rdma_lookup_put_uobject(struct ib_uobject *uobj,
			     enum rdma_lookup_mode mode)
{ … }

void setup_ufile_idr_uobject(struct ib_uverbs_file *ufile)
{ … }

void release_ufile_idr_uobject(struct ib_uverbs_file *ufile)
{ … }

const struct uverbs_obj_type_class uverbs_idr_class = …;
EXPORT_SYMBOL(…);

/*
 * Users of UVERBS_TYPE_ALLOC_FD should set this function as the struct
 * file_operations release method.
 */
int uverbs_uobject_fd_release(struct inode *inode, struct file *filp)
{ … }
EXPORT_SYMBOL(…);

/*
 * Drop the ucontext off the ufile and completely disconnect it from the
 * ib_device
 */
static void ufile_destroy_ucontext(struct ib_uverbs_file *ufile,
				   enum rdma_remove_reason reason)
{ … }

static int __uverbs_cleanup_ufile(struct ib_uverbs_file *ufile,
				  enum rdma_remove_reason reason)
{ … }

/*
 * Destroy the ucontext and every uobject associated with it.
 *
 * This is internally locked and can be called in parallel from multiple
 * contexts.
 */
void uverbs_destroy_ufile_hw(struct ib_uverbs_file *ufile,
			     enum rdma_remove_reason reason)
{ … }

const struct uverbs_obj_type_class uverbs_fd_class = …;
EXPORT_SYMBOL(…);

struct ib_uobject *
uverbs_get_uobject_from_file(u16 object_id, enum uverbs_obj_access access,
			     s64 id, struct uverbs_attr_bundle *attrs)
{ … }

void uverbs_finalize_object(struct ib_uobject *uobj,
			    enum uverbs_obj_access access, bool hw_obj_valid,
			    bool commit, struct uverbs_attr_bundle *attrs)
{ … }
linux/drivers/infiniband/core/rdma_core.c
