выделить и освободить родительский объект домена (allocate and deallocate the parent domain object)
Имя (Name)
ibv_alloc_parent_domain(), ibv_dealloc_pd() - allocate and
deallocate the parent domain object
Синопсис (Synopsis)
#include <infiniband/verbs.h>
struct ibv_pd *ibv_alloc_parent_domain(struct ibv_context *context", struct ibv_parent_domain_init_attr *attr);
Описание (Description)
ibv_alloc_parent_domain() allocates a parent domain object for
the RDMA device context context.
The parent domain object extends the normal protection domain
with additional objects, such as a thread domain.
A parent domain is completely interchangeable with the struct
ibv_pd used to create it, and can be used as an input argument to
any function accepting a struct ibv_pd.
The behavior of each verb may be different if the verb is passed
a parent domain struct ibv_pd that contains a struct ibv_td
pointer. For instance the verb may choose to share resources
between objects using the same thread domain. The exact behavior
is provider dependent.
The attr argument specifies the following:
enum ibv_parent_domain_init_attr_mask {
IBV_PARENT_DOMAIN_INIT_ATTR_ALLOCATORS = 1 << 0,
IBV_PARENT_DOMAIN_INIT_ATTR_PD_CONTEXT = 1 << 1,
};
struct ibv_parent_domain_init_attr {
struct ibv_pd *pd; /* reference to a protection domain, can't be NULL */
struct ibv_td *td; /* reference to a thread domain, or NULL */
uint32_t comp_mask;
void *(*alloc)(struct ibv_pd *pd, void *pd_context, size_t size,
size_t alignment, uint64_t resource_type);
void (*free)(struct ibv_pd *pd, void *pd_context, void *ptr,
uint64_t resource_type);
void *pd_context;
};
ibv_dealloc_pd() will deallocate the parent domain as its exposed
as an ibv_pd pd. All resources created with the parent domain
should be destroyed prior to deallocating the parent domain.
Аргументы (Arguments)
pd Reference to the protection domain that this parent domain
uses.
td An optional thread domain that the parent domain uses.
comp_mask Bit-mask of optional fields in the
ibv_parent_domain_init_attr struct.
alloc Custom memory allocation function for this parent domain.
Provider memory allocations will use this function to allocate
the needed memory. The allocation function is passed the parent
domain pd and the user-specified context pd_context. In
addition, the callback receives the size and the alignment of the
requested buffer, as well a vendor-specific resource_type , which
is derived from the rdma_driver_id enum (upper 32 bits) and a
vendor specific resource code. The function returns the pointer
to the allocated buffer, or NULL to designate an error. It may
also return IBV_ALLOCATOR_USE_DEFAULT asking the callee to
allocate the buffer using the default allocator.
The callback makes sure the allocated buffer is initialized with
zeros. It is also the responsibility of the callback to make sure
the memory cannot be COWed, e.g. by using madvise(MADV_DONTFORK)
or by allocating anonymous shared memory.
free Callback to free memory buffers that were allocated using a
successful alloc().
pd_context A pointer for additional user-specific data to be
associated with this parent domain. The pointer is passed back to
the custom allocator functions.
Возвращаемое значение (Return value)
ibv_alloc_parent_domain() returns a pointer to the allocated
struct ibv_pd object, or NULL if the request fails (and sets
errno to indicate the failure reason).
Смотри также (See also)
ibv_alloc_parent_domain(3), ibv_dealloc_pd(3), ibv_alloc_pd(3),
ibv_alloc_td(3)
