linux/include/rdma/ib_umem.h
Gal Pressman 1e4df4a21c RDMA/umem: Allow pinned dmabuf umem usage
Introduce ib_umem_dmabuf_get_pinned() which allows the driver to get a
dmabuf umem which is pinned and does not require move_notify callback
implementation.

The returned umem is pinned and DMA mapped like standard cpu umems, and is
released through ib_umem_release() (incl. unpinning and unmapping).

Link: https://lore.kernel.org/r/20211012120903.96933-3-galpress@amazon.com
Signed-off-by: Gal Pressman <galpress@amazon.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2021-10-28 08:58:26 -03:00

202 lines
6.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
* Copyright (c) 2007 Cisco Systems. All rights reserved.
* Copyright (c) 2020 Intel Corporation. All rights reserved.
*/
#ifndef IB_UMEM_H
#define IB_UMEM_H
#include <linux/list.h>
#include <linux/scatterlist.h>
#include <linux/workqueue.h>
#include <rdma/ib_verbs.h>
struct ib_ucontext;
struct ib_umem_odp;
struct dma_buf_attach_ops;
struct ib_umem {
struct ib_device *ibdev;
struct mm_struct *owning_mm;
u64 iova;
size_t length;
unsigned long address;
u32 writable : 1;
u32 is_odp : 1;
u32 is_dmabuf : 1;
struct work_struct work;
struct sg_append_table sgt_append;
};
struct ib_umem_dmabuf {
struct ib_umem umem;
struct dma_buf_attachment *attach;
struct sg_table *sgt;
struct scatterlist *first_sg;
struct scatterlist *last_sg;
unsigned long first_sg_offset;
unsigned long last_sg_trim;
void *private;
u8 pinned : 1;
};
static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
{
return container_of(umem, struct ib_umem_dmabuf, umem);
}
/* Returns the offset of the umem start relative to the first page. */
static inline int ib_umem_offset(struct ib_umem *umem)
{
return umem->address & ~PAGE_MASK;
}
static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
unsigned long pgsz)
{
return (sg_dma_address(umem->sgt_append.sgt.sgl) + ib_umem_offset(umem)) &
(pgsz - 1);
}
static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
unsigned long pgsz)
{
return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
ALIGN_DOWN(umem->iova, pgsz))) /
pgsz;
}
static inline size_t ib_umem_num_pages(struct ib_umem *umem)
{
return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
}
static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
struct ib_umem *umem,
unsigned long pgsz)
{
__rdma_block_iter_start(biter, umem->sgt_append.sgt.sgl,
umem->sgt_append.sgt.nents, pgsz);
}
/**
* rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
* @umem: umem to iterate over
* @pgsz: Page size to split the list into
*
* pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
* returned DMA blocks will be aligned to pgsz and span the range:
* ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
*
* Performs exactly ib_umem_num_dma_blocks() iterations.
*/
#define rdma_umem_for_each_dma_block(umem, biter, pgsz) \
for (__rdma_umem_block_iter_start(biter, umem, pgsz); \
__rdma_block_iter_next(biter);)
#ifdef CONFIG_INFINIBAND_USER_MEM
struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
size_t size, int access);
void ib_umem_release(struct ib_umem *umem);
int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
size_t length);
unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
unsigned long pgsz_bitmap,
unsigned long virt);
/**
* ib_umem_find_best_pgoff - Find best HW page size
*
* @umem: umem struct
* @pgsz_bitmap bitmap of HW supported page sizes
* @pgoff_bitmask: Mask of bits that can be represented with an offset
*
* This is very similar to ib_umem_find_best_pgsz() except instead of accepting
* an IOVA it accepts a bitmask specifying what address bits can be represented
* with a page offset.
*
* For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
* and can support aligned offsets up to 4032 then pgoff_bitmask would be
* "111111000000".
*
* If the pgoff_bitmask requires either alignment in the low bit or an
* unavailable page size for the high bits, this function returns 0.
*/
static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
unsigned long pgsz_bitmap,
u64 pgoff_bitmask)
{
struct scatterlist *sg = umem->sgt_append.sgt.sgl;
dma_addr_t dma_addr;
dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
dma_addr & pgoff_bitmask);
}
struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
unsigned long offset, size_t size,
int fd, int access,
const struct dma_buf_attach_ops *ops);
struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
unsigned long offset,
size_t size, int fd,
int access);
int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
#else /* CONFIG_INFINIBAND_USER_MEM */
#include <linux/err.h>
static inline struct ib_umem *ib_umem_get(struct ib_device *device,
unsigned long addr, size_t size,
int access)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline void ib_umem_release(struct ib_umem *umem) { }
static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
size_t length) {
return -EOPNOTSUPP;
}
static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
unsigned long pgsz_bitmap,
unsigned long virt)
{
return 0;
}
static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
unsigned long pgsz_bitmap,
u64 pgoff_bitmask)
{
return 0;
}
static inline
struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
unsigned long offset,
size_t size, int fd,
int access,
struct dma_buf_attach_ops *ops)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline struct ib_umem_dmabuf *
ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
size_t size, int fd, int access)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
{
return -EOPNOTSUPP;
}
static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
#endif /* CONFIG_INFINIBAND_USER_MEM */
#endif /* IB_UMEM_H */