Replace struct rxe-phys_buf and struct rxe_map by struct xarray in rxe_verbs.h. This allows using rcu locking on reads for the memory maps stored in each mr. This is based off of a sketch of a patch from Jason Gunthorpe in the link below. Some changes were needed to make this work. It applies cleanly to the current for-next and passes the pyverbs, perftest and the same blktests test cases which run today. Link: https://lore.kernel.org/linux-rdma/Y3gvZr6%2FNCii9Avy@xxxxxxxxxx/ Co-developed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Bob Pearson <rpearsonhpe@xxxxxxxxx> --- drivers/infiniband/sw/rxe/rxe_loc.h | 1 - drivers/infiniband/sw/rxe/rxe_mr.c | 481 ++++++++++++-------------- drivers/infiniband/sw/rxe/rxe_resp.c | 5 +- drivers/infiniband/sw/rxe/rxe_verbs.h | 21 +- 4 files changed, 226 insertions(+), 282 deletions(-) diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h index e1bb977cdbc0..e5b6582e6b96 100644 --- a/drivers/infiniband/sw/rxe/rxe_loc.h +++ b/drivers/infiniband/sw/rxe/rxe_loc.h @@ -70,7 +70,6 @@ int copy_data(struct rxe_pd *pd, int access, struct rxe_dma_info *dma, void *addr, int length, enum rxe_mr_copy_dir dir); int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents, unsigned int *sg_offset); -void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length); int rxe_mr_do_atomic_op(struct rxe_mr *mr, u64 iova, int opcode, u64 compare, u64 swap_add, u64 *orig_val); int rxe_mr_do_atomic_write(struct rxe_mr *mr, u64 iova, void *addr); diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c index 2b600557fbfa..d8eaceca1b62 100644 --- a/drivers/infiniband/sw/rxe/rxe_mr.c +++ b/drivers/infiniband/sw/rxe/rxe_mr.c @@ -58,127 +58,108 @@ static void rxe_mr_init(int access, struct rxe_mr *mr) mr->lkey = mr->ibmr.lkey = lkey; mr->rkey = mr->ibmr.rkey = rkey; + mr->access = access; mr->ibmr.page_size = PAGE_SIZE; mr->page_mask = PAGE_MASK; mr->page_shift = PAGE_SHIFT; mr->state = RXE_MR_STATE_INVALID; } -static int rxe_mr_alloc(struct rxe_mr *mr, int num_buf) +void rxe_mr_init_dma(int access, struct rxe_mr *mr) { - int i; - int num_map; - struct rxe_map **map = mr->map; - - num_map = (num_buf + RXE_BUF_PER_MAP - 1) / RXE_BUF_PER_MAP; - - mr->map = kmalloc_array(num_map, sizeof(*map), GFP_KERNEL); - if (!mr->map) - goto err1; - - for (i = 0; i < num_map; i++) { - mr->map[i] = kmalloc(sizeof(**map), GFP_KERNEL); - if (!mr->map[i]) - goto err2; - } - - BUILD_BUG_ON(!is_power_of_2(RXE_BUF_PER_MAP)); + rxe_mr_init(access, mr); - mr->map_shift = ilog2(RXE_BUF_PER_MAP); - mr->map_mask = RXE_BUF_PER_MAP - 1; + mr->state = RXE_MR_STATE_VALID; + mr->ibmr.type = IB_MR_TYPE_DMA; +} - mr->num_buf = num_buf; - mr->num_map = num_map; - mr->max_buf = num_map * RXE_BUF_PER_MAP; +static unsigned long rxe_mr_iova_to_index(struct rxe_mr *mr, u64 iova) +{ + return (iova >> mr->page_shift) - (mr->ibmr.iova >> mr->page_shift); +} - return 0; +static int rxe_mr_fill_pages_from_sgt(struct rxe_mr *mr, struct sg_table *sgt) +{ + XA_STATE(xas, &mr->pages, 0); + struct sg_page_iter sg_iter; -err2: - for (i--; i >= 0; i--) - kfree(mr->map[i]); + xa_init(&mr->pages); - kfree(mr->map); - mr->map = NULL; -err1: - return -ENOMEM; -} + __sg_page_iter_start(&sg_iter, sgt->sgl, sgt->orig_nents, 0); + if (!__sg_page_iter_next(&sg_iter)) + return 0; -void rxe_mr_init_dma(int access, struct rxe_mr *mr) -{ - rxe_mr_init(access, mr); + do { + xas_lock(&xas); + while (true) { + xas_store(&xas, sg_page_iter_page(&sg_iter)); + if (xas_error(&xas)) + break; + xas_next(&xas); + if (!__sg_page_iter_next(&sg_iter)) + break; + } + xas_unlock(&xas); + } while (xas_nomem(&xas, GFP_KERNEL)); - mr->access = access; - mr->state = RXE_MR_STATE_VALID; - mr->ibmr.type = IB_MR_TYPE_DMA; + return xas_error(&xas); } int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova, int access, struct rxe_mr *mr) { - struct rxe_map **map; - struct rxe_phys_buf *buf = NULL; - struct ib_umem *umem; - struct sg_page_iter sg_iter; - int num_buf; - void *vaddr; + struct ib_umem *umem; int err; + rxe_mr_init(access, mr); + umem = ib_umem_get(&rxe->ib_dev, start, length, access); if (IS_ERR(umem)) { rxe_dbg_mr(mr, "Unable to pin memory region err = %d\n", (int)PTR_ERR(umem)); - err = PTR_ERR(umem); - goto err_out; + return PTR_ERR(umem); } - num_buf = ib_umem_num_pages(umem); - - rxe_mr_init(access, mr); - - err = rxe_mr_alloc(mr, num_buf); + err = rxe_mr_fill_pages_from_sgt(mr, &umem->sgt_append.sgt); if (err) { - rxe_dbg_mr(mr, "Unable to allocate memory for map\n"); - goto err_release_umem; + ib_umem_release(umem); + return err; } - num_buf = 0; - map = mr->map; - if (length > 0) { - buf = map[0]->buf; + mr->umem = umem; + mr->ibmr.type = IB_MR_TYPE_USER; + mr->state = RXE_MR_STATE_VALID; - for_each_sgtable_page (&umem->sgt_append.sgt, &sg_iter, 0) { - if (num_buf >= RXE_BUF_PER_MAP) { - map++; - buf = map[0]->buf; - num_buf = 0; - } + return 0; +} - vaddr = page_address(sg_page_iter_page(&sg_iter)); - if (!vaddr) { - rxe_dbg_mr(mr, "Unable to get virtual address\n"); - err = -ENOMEM; - goto err_release_umem; - } - buf->addr = (uintptr_t)vaddr; - buf->size = mr_page_size(mr); - num_buf++; - buf++; +static int rxe_mr_alloc(struct rxe_mr *mr, int num_buf) +{ + XA_STATE(xas, &mr->pages, 0); + int i = 0; + int err; + + xa_init(&mr->pages); + do { + xas_lock(&xas); + while (i != num_buf) { + xas_store(&xas, XA_ZERO_ENTRY); + if (xas_error(&xas)) + break; + xas_next(&xas); + i++; } - } + xas_unlock(&xas); + } while (xas_nomem(&xas, GFP_KERNEL)); - mr->umem = umem; - mr->access = access; - mr->page_offset = ib_umem_offset(umem); - mr->state = RXE_MR_STATE_VALID; - mr->ibmr.type = IB_MR_TYPE_USER; + err = xas_error(&xas); + if (err) + return err; - return 0; + mr->num_buf = num_buf; -err_release_umem: - ib_umem_release(umem); -err_out: - return err; + return 0; } int rxe_mr_init_fast(int max_pages, struct rxe_mr *mr) @@ -192,7 +173,6 @@ int rxe_mr_init_fast(int max_pages, struct rxe_mr *mr) if (err) goto err1; - mr->max_buf = max_pages; mr->state = RXE_MR_STATE_FREE; mr->ibmr.type = IB_MR_TYPE_MEM_REG; @@ -202,193 +182,142 @@ int rxe_mr_init_fast(int max_pages, struct rxe_mr *mr) return err; } -static int rxe_set_page(struct ib_mr *ibmr, u64 addr) +static int rxe_set_page(struct ib_mr *ibmr, u64 iova) { struct rxe_mr *mr = to_rmr(ibmr); - struct rxe_map *map; - struct rxe_phys_buf *buf; + struct page *page = virt_to_page(iova & mr->page_mask); + XA_STATE(xas, &mr->pages, mr->nbuf); + int err; if (unlikely(mr->nbuf == mr->num_buf)) return -ENOMEM; - map = mr->map[mr->nbuf / RXE_BUF_PER_MAP]; - buf = &map->buf[mr->nbuf % RXE_BUF_PER_MAP]; + do { + xas_lock(&xas); + xas_store(&xas, page); + xas_unlock(&xas); + } while (xas_nomem(&xas, GFP_KERNEL)); - buf->addr = addr; - buf->size = ibmr->page_size; - mr->nbuf++; + err = xas_error(&xas); + if (err) + return err; + mr->nbuf++; return 0; } -int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, +int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sgl, int sg_nents, unsigned int *sg_offset) { struct rxe_mr *mr = to_rmr(ibmr); unsigned int page_size = mr_page_size(mr); + mr->nbuf = 0; mr->page_shift = ilog2(page_size); mr->page_mask = ~((u64)page_size - 1); - mr->page_offset = ibmr->iova & (page_size - 1); - - mr->nbuf = 0; + mr->page_offset = mr->ibmr.iova & (page_size - 1); - return ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset, rxe_set_page); + return ib_sg_to_pages(ibmr, sgl, sg_nents, sg_offset, rxe_set_page); } -static void lookup_iova(struct rxe_mr *mr, u64 iova, int *m_out, int *n_out, - size_t *offset_out) +/* + * TODO: Attempting to modify the mr page map between the time + * a packet is received and the map is referenced as here + * in xa_load(&mr->pages) will cause problems. It is OK to + * deregister the mr since the mr reference counts will preserve + * it until memory accesses are complete. Currently reregister mr + * operations are not supported by the rxe driver but could be + * in the future. Invalidate followed by fast_reg mr will change + * the map and then the rkey so delayed packets arriving in the + * middle could use the wrong map entries. This isn't new but was + * already the case in the earlier implementation. This won't be + * a problem for well behaved programs which wait until all the + * outstanding packets for the first FMR before remapping to the + * second. + */ +static int rxe_mr_copy_xarray(struct rxe_mr *mr, void *addr, + unsigned long index, + unsigned int page_offset, unsigned int length, + enum rxe_mr_copy_dir dir) { - size_t offset = iova - mr->ibmr.iova + mr->page_offset; - int map_index; - int buf_index; - u64 length; - - if (likely(mr->page_shift)) { - *offset_out = offset & (mr_page_size(mr) - 1); - offset >>= mr->page_shift; - *n_out = offset & mr->map_mask; - *m_out = offset >> mr->map_shift; - } else { - map_index = 0; - buf_index = 0; - - length = mr->map[map_index]->buf[buf_index].size; - - while (offset >= length) { - offset -= length; - buf_index++; - - if (buf_index == RXE_BUF_PER_MAP) { - map_index++; - buf_index = 0; - } - length = mr->map[map_index]->buf[buf_index].size; - } + struct page *page; + unsigned int bytes; + void *va; - *m_out = map_index; - *n_out = buf_index; - *offset_out = offset; + while (length) { + page = xa_load(&mr->pages, index); + if (WARN_ON(!page)) + return -EINVAL; + + bytes = min_t(unsigned int, length, + mr_page_size(mr) - page_offset); + va = kmap_local_page(page); + if (dir == RXE_FROM_MR_OBJ) + memcpy(addr, va + page_offset, bytes); + else + memcpy(va + page_offset, addr, bytes); + kunmap_local(va); + + page_offset = 0; + addr += bytes; + length -= bytes; + index++; } + + return 0; } -void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length) +static void rxe_mr_copy_dma(struct rxe_mr *mr, u64 iova, void *addr, + unsigned int page_offset, unsigned int length, + enum rxe_mr_copy_dir dir) { - size_t offset; - int m, n; - void *addr; - - if (mr->state != RXE_MR_STATE_VALID) { - rxe_dbg_mr(mr, "Not in valid state\n"); - addr = NULL; - goto out; - } - - if (!mr->map) { - addr = (void *)(uintptr_t)iova; - goto out; - } - - if (mr_check_range(mr, iova, length)) { - rxe_dbg_mr(mr, "Range violation\n"); - addr = NULL; - goto out; - } - - lookup_iova(mr, iova, &m, &n, &offset); + unsigned int bytes; + struct page *page; + u8 *va; - if (offset + length > mr->map[m]->buf[n].size) { - rxe_dbg_mr(mr, "Crosses page boundary\n"); - addr = NULL; - goto out; + while (length) { + page = virt_to_page(iova & mr->page_mask); + va = kmap_local_page(page); + bytes = min_t(unsigned int, length, PAGE_SIZE - page_offset); + + if (dir == RXE_TO_MR_OBJ) + memcpy(va + page_offset, addr, bytes); + else + memcpy(addr, va + page_offset, bytes); + + kunmap_local(va); + page_offset = 0; + iova += bytes; + addr += bytes; + length -= bytes; } - - addr = (void *)(uintptr_t)mr->map[m]->buf[n].addr + offset; - -out: - return addr; } -/* copy data from a range (vaddr, vaddr+length-1) to or from - * a mr object starting at iova. - */ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length, enum rxe_mr_copy_dir dir) { - int err; - int bytes; - u8 *va; - struct rxe_map **map; - struct rxe_phys_buf *buf; - int m; - int i; - size_t offset; + unsigned int page_offset; + unsigned long index; + int err; if (length == 0) return 0; if (mr->ibmr.type == IB_MR_TYPE_DMA) { - u8 *src, *dest; - - src = (dir == RXE_TO_MR_OBJ) ? addr : ((void *)(uintptr_t)iova); - - dest = (dir == RXE_TO_MR_OBJ) ? ((void *)(uintptr_t)iova) : addr; - - memcpy(dest, src, length); - + page_offset = iova & (PAGE_SIZE - 1); + rxe_mr_copy_dma(mr, iova, addr, page_offset, length, dir); return 0; } - WARN_ON_ONCE(!mr->map); - err = mr_check_range(mr, iova, length); - if (err) { - err = -EFAULT; - goto err1; - } - - lookup_iova(mr, iova, &m, &i, &offset); - - map = mr->map + m; - buf = map[0]->buf + i; - - while (length > 0) { - u8 *src, *dest; - - va = (u8 *)(uintptr_t)buf->addr + offset; - src = (dir == RXE_TO_MR_OBJ) ? addr : va; - dest = (dir == RXE_TO_MR_OBJ) ? va : addr; - - bytes = buf->size - offset; - - if (bytes > length) - bytes = length; - - memcpy(dest, src, bytes); - - length -= bytes; - addr += bytes; - - offset = 0; - buf++; - i++; - - if (i == RXE_BUF_PER_MAP) { - i = 0; - map++; - buf = map[0]->buf; - } - } - - return 0; + if (err) + return err; -err1: - return err; + page_offset = iova & (mr_page_size(mr) - 1); + index = rxe_mr_iova_to_index(mr, iova); + return rxe_mr_copy_xarray(mr, addr, index, page_offset, length, dir); } -/* copy data in or out of a wqe, i.e. sg list - * under the control of a dma descriptor - */ int copy_data( struct rxe_pd *pd, int access, @@ -455,7 +384,6 @@ int copy_data( if (bytes > 0) { iova = sge->addr + offset; - err = rxe_mr_copy(mr, iova, addr, bytes, dir); if (err) goto err2; @@ -484,20 +412,47 @@ int copy_data( static DEFINE_SPINLOCK(atomic_ops_lock); +/* + * Returns: + * 0 on success + * -1 address is misaligned + * -2 access violations + */ int rxe_mr_do_atomic_op(struct rxe_mr *mr, u64 iova, int opcode, u64 compare, u64 swap_add, u64 *orig_val) { - u64 *vaddr = iova_to_vaddr(mr, iova, sizeof(u64)); + unsigned int page_offset; + struct page *page; u64 value; + u64 *va; - /* needs to match rxe_resp.c */ - if (mr->state != RXE_MR_STATE_VALID || !vaddr) - return -EFAULT; - if ((uintptr_t)vaddr & 7) - return -EINVAL; + if (unlikely(mr->state != RXE_MR_STATE_VALID)) + return -2; + + if (mr->ibmr.type == IB_MR_TYPE_DMA) { + page_offset = iova & (PAGE_SIZE - 1); + page = virt_to_page(iova & PAGE_MASK); + } else { + unsigned long index; + int err; + + err = mr_check_range(mr, iova, 8); + if (err) + return err; + page_offset = iova & (mr_page_size(mr) - 1); + index = rxe_mr_iova_to_index(mr, iova); + page = xa_load(&mr->pages, index); + if (!page) + return -2; + } + + if (unlikely(page_offset & 0x7)) + return -1; + + va = kmap_local_page(page); spin_lock_bh(&atomic_ops_lock); - value = *orig_val = *vaddr; + *orig_val = value = va[page_offset >> 3]; if (opcode == IB_OPCODE_RC_COMPARE_SWAP) { if (value == compare) @@ -506,9 +461,11 @@ int rxe_mr_do_atomic_op(struct rxe_mr *mr, u64 iova, int opcode, value += swap_add; } - *vaddr = value; + va[page_offset >> 3] = value; spin_unlock_bh(&atomic_ops_lock); + kunmap_local(va); + return 0; } @@ -520,9 +477,11 @@ int rxe_mr_do_atomic_op(struct rxe_mr *mr, u64 iova, int opcode, */ int rxe_mr_do_atomic_write(struct rxe_mr *mr, u64 iova, void *addr) { - u64 *vaddr; - u64 value; + unsigned int page_offset; + struct page *page; unsigned int length = 8; + u64 value; + u64 *va; /* See IBA oA19-28 */ if (unlikely(mr->state != RXE_MR_STATE_VALID)) { @@ -530,23 +489,38 @@ int rxe_mr_do_atomic_write(struct rxe_mr *mr, u64 iova, void *addr) return -2; } + if (mr->ibmr.type == IB_MR_TYPE_DMA) { + page_offset = iova & (PAGE_SIZE - 1); + page = virt_to_page(iova & PAGE_MASK); + } else { + unsigned long index; + int err; + + /* See IBA oA19-28 */ + err = mr_check_range(mr, iova, length); + if (unlikely(err)) { + rxe_dbg_mr(mr, "iova out of range"); + return -2; + } + page_offset = iova & (mr_page_size(mr) - 1); + index = rxe_mr_iova_to_index(mr, iova); + page = xa_load(&mr->pages, index); + if (WARN_ON(!page)) + return -2; + } + /* See IBA A19.4.2 */ - if (unlikely((uintptr_t)vaddr & 0x7 || iova & 0x7)) { + if (iova & 0x7) { rxe_dbg_mr(mr, "misaligned address"); return -1; } - vaddr = iova_to_vaddr(mr, iova, length); - if (unlikely(!vaddr)) { - rxe_dbg_mr(mr, "iova out of range"); - return -2; - } - - /* this makes no sense. What of payload is not 8? */ + va = kmap_local_page(page); memcpy(&value, addr, length); /* Do atomic write after all prior operations have completed */ - smp_store_release(vaddr, value); + smp_store_release(&va[page_offset >> 3], value); + kunmap_local(va); return 0; } @@ -584,12 +558,6 @@ int advance_dma_data(struct rxe_dma_info *dma, unsigned int length) return 0; } -/* (1) find the mr corresponding to lkey/rkey - * depending on lookup_type - * (2) verify that the (qp) pd matches the mr pd - * (3) verify that the mr can support the requested access - * (4) verify that mr state is valid - */ struct rxe_mr *lookup_mr(struct rxe_pd *pd, int access, u32 key, enum rxe_mr_lookup_type type) { @@ -710,15 +678,8 @@ int rxe_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata) void rxe_mr_cleanup(struct rxe_pool_elem *elem) { struct rxe_mr *mr = container_of(elem, typeof(*mr), elem); - int i; rxe_put(mr_pd(mr)); ib_umem_release(mr->umem); - - if (mr->map) { - for (i = 0; i < mr->num_map; i++) - kfree(mr->map[i]); - - kfree(mr->map); - } + xa_destroy(&mr->pages); } diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c index abe9cfd935c2..188e7315158a 100644 --- a/drivers/infiniband/sw/rxe/rxe_resp.c +++ b/drivers/infiniband/sw/rxe/rxe_resp.c @@ -635,7 +635,7 @@ static enum resp_states atomic_reply(struct rxe_qp *qp, atmeth_comp(pkt), atmeth_swap_add(pkt), &res->atomic.orig_val); - if (err == -EINVAL) + if (err == -1) return RESPST_ERR_MISALIGNED_ATOMIC; else if (err) return RESPST_ERR_RKEY_VIOLATION; @@ -659,6 +659,7 @@ static enum resp_states atomic_write_reply(struct rxe_qp *qp, struct resp_res *res = qp->resp.res; struct rxe_mr *mr = qp->resp.mr; void *addr = payload_addr(pkt); + unsigned int length = 8; int err; if (!res) { @@ -676,7 +677,7 @@ static enum resp_states atomic_write_reply(struct rxe_qp *qp, else return RESPST_ERR_RKEY_VIOLATION; - qp->resp.resid -= 8; + qp->resp.resid -= length; qp->resp.msn++; /* next expected psn, read handles this separately */ diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h index ddaa4de5e1c7..7f360c402473 100644 --- a/drivers/infiniband/sw/rxe/rxe_verbs.h +++ b/drivers/infiniband/sw/rxe/rxe_verbs.h @@ -277,17 +277,6 @@ enum rxe_mr_lookup_type { RXE_LOOKUP_REMOTE, }; -#define RXE_BUF_PER_MAP (PAGE_SIZE / sizeof(struct rxe_phys_buf)) - -struct rxe_phys_buf { - u64 addr; - u64 size; -}; - -struct rxe_map { - struct rxe_phys_buf buf[RXE_BUF_PER_MAP]; -}; - static inline int rkey_is_mw(u32 rkey) { u32 index = rkey >> 8; @@ -305,22 +294,16 @@ struct rxe_mr { u32 rkey; enum rxe_mr_state state; int access; + atomic_t num_mw; unsigned int page_offset; unsigned int page_shift; u64 page_mask; - int map_shift; - int map_mask; u32 num_buf; u32 nbuf; - u32 max_buf; - u32 num_map; - - atomic_t num_mw; - - struct rxe_map **map; + struct xarray pages; }; static inline unsigned int mr_page_size(struct rxe_mr *mr) -- 2.37.2
