RDMA/umem: Add API to find best driver supported page size in an MR (4a353399) · Commits · 戴 / test

drivers/infiniband/core/umem.c

+51 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,57 @@ static struct scatterlist ib_umem_add_sg_table(struct scatterlist sg,
		return sg;
		}

		/**
		* ib_umem_find_best_pgsz - Find best HW page size to use for this MR
		*
		* @umem: umem struct
		* @pgsz_bitmap: bitmap of HW supported page sizes
		* @virt: IOVA
		*
		* This helper is intended for HW that support multiple page
		* sizes but can do only a single page size in an MR.
		*
		* Returns 0 if the umem requires page sizes not supported by
		* the driver to be mapped. Drivers always supporting PAGE_SIZE
		* or smaller will never see a 0 result.
		*/
		unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
		unsigned long pgsz_bitmap,
		unsigned long virt)
		{
		struct scatterlist *sg;
		unsigned int best_pg_bit;
		unsigned long va, pgoff;
		dma_addr_t mask;
		int i;

		/* At minimum, drivers must support PAGE_SIZE or smaller */
		if (WARN_ON(!(pgsz_bitmap & GENMASK(PAGE_SHIFT, 0))))
		return 0;

		va = virt;
		/* max page size not to exceed MR length */
		mask = roundup_pow_of_two(umem->length);
		/* offset into first SGL */
		pgoff = umem->address & ~PAGE_MASK;

		for_each_sg(umem->sg_head.sgl, sg, umem->nmap, i) {
		/* Walk SGL and reduce max page size if VA/PA bits differ
		* for any address.
		*/
		mask \|= (sg_dma_address(sg) + pgoff) ^ va;
		if (i && i != (umem->nmap - 1))
		/* restrict by length as well for interior SGEs */
		mask \|= sg_dma_len(sg);
		va += sg_dma_len(sg) - pgoff;
		pgoff = 0;
		}
		best_pg_bit = rdma_find_pg_bit(mask, pgsz_bitmap);

		return BIT_ULL(best_pg_bit);
		}
		EXPORT_SYMBOL(ib_umem_find_best_pgsz);

		/**
		* ib_umem_get - Pin and DMA map userspace memory.
		*

include/rdma/ib_umem.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -87,6 +87,9 @@ void ib_umem_release(struct ib_umem *umem);
		int ib_umem_page_count(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);

		#else /* CONFIG_INFINIBAND_USER_MEM */

		@@ -104,6 +107,12 @@ static inline int ib_umem_copy_from(void dst, struct ib_umem umem, size_t offs
		size_t length) {
		return -EINVAL;
		}
		static inline int ib_umem_find_best_pgsz(struct ib_umem *umem,
		unsigned long pgsz_bitmap,
		unsigned long virt) {
		return -EINVAL;
		}

		#endif /* CONFIG_INFINIBAND_USER_MEM */

		#endif /* IB_UMEM_H */

include/rdma/ib_verbs.h

+24 −0

Original line number	Diff line number	Diff line
		@@ -3250,6 +3250,30 @@ static inline bool rdma_cap_read_inv(struct ib_device *dev, u32 port_num)
		return rdma_protocol_iwarp(dev, port_num);
		}

		/**
		* rdma_find_pg_bit - Find page bit given address and HW supported page sizes
		*
		* @addr: address
		* @pgsz_bitmap: bitmap of HW supported page sizes
		*/
		static inline unsigned int rdma_find_pg_bit(unsigned long addr,
		unsigned long pgsz_bitmap)
		{
		unsigned long align;
		unsigned long pgsz;

		align = addr & -addr;

		/* Find page bit such that addr is aligned to the highest supported
		* HW page size
		*/
		pgsz = pgsz_bitmap & ~(-align << 1);
		if (!pgsz)
		return __ffs(pgsz_bitmap);

		return __fls(pgsz);
		}

		int ib_set_vf_link_state(struct ib_device *device, int vf, u8 port,
		int state);
		int ib_get_vf_config(struct ib_device *device, int vf, u8 port,

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