diff options
| -rw-r--r-- | drivers/infiniband/core/umem.c | 51 | ||||
| -rw-r--r-- | include/rdma/ib_umem.h | 9 | ||||
| -rw-r--r-- | include/rdma/ib_verbs.h | 24 |
3 files changed, 84 insertions, 0 deletions
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 23f7512cc7a8..145c31c530ae 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -131,6 +131,57 @@ static struct scatterlist *ib_umem_add_sg_table(struct scatterlist *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. * * If access flags indicate ODP memory, avoid pinning. Instead, stores diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h index b13a2e9a50d4..917b687010f0 100644 --- a/include/rdma/ib_umem.h +++ b/include/rdma/ib_umem.h @@ -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 */ diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 8f8965f8ffdb..03b07ec6a34b 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -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, |