Re: [PATCH] RDMA/rxe: Replace page_address() with kmap_local_page()

Yang, Xiao/杨 晓
2022-11-11T08:10:16Z

On 2022/11/11 11:52, Li, Zhijian/李 智坚 wrote:
> Xiao,
>
> What a coincidence!! i aslo had a similar patches do the same thing.
> which would be more easy to be reviewed, i will post it as well. You are
> free to use any of this or ignore it.

Hi Zhijian,

Thanks a lot for your reference.

Li Zhijian (5):
RDMA/rxe: Remove rxe_phys_buf.size
-> It has been included in my first patch[1].
RDMA/rxe: use iova_to_vaddr to transform iova for rxe_mr_copy
-> I don't want to do the check (e.g. mr_check_range()) in loops.
RDMA/rxe: iova_to_vaddr cleanup
RDMA/rxe: refactor iova_to_vaddr
RDMA/rxe: Rename iova_to_vaddr to rxe_map_iova
-> I think these three are similar to my second patch[2].

[1]:
https://lore.kernel.org/linux-rdma/1668153085-15-1-git-send-email-yangx.jy@fujitsu.com/T/#t
[2]:
https://lore.kernel.org/linux-rdma/1668153085-15-2-git-send-email-yangx.jy@fujitsu.com/T/#u

Best Regards,
Xiao Yang

>
>
> Thanks
> Zhijian
>
>
>
>
> On 11/11/2022 11:19, Xiao Yang wrote:
>> 1) Use kmap_local_page() for new in-kernel memory protection schemes.
>> 2) Do some cleanup(e.g. remove struct rxe_phys_buf).
>>
>> Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
>> ---
>> drivers/infiniband/sw/rxe/rxe_loc.h | 2 +
>> drivers/infiniband/sw/rxe/rxe_mr.c | 84 +++++++++++++--------------
>> drivers/infiniband/sw/rxe/rxe_resp.c | 1 +
>> drivers/infiniband/sw/rxe/rxe_verbs.c | 6 +-
>> drivers/infiniband/sw/rxe/rxe_verbs.h | 9 +--
>> 5 files changed, 45 insertions(+), 57 deletions(-)
>>
>> diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
>> index c2a5c8814a48..a63d29156a66 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_loc.h
>> +++ b/drivers/infiniband/sw/rxe/rxe_loc.h
>> @@ -68,6 +68,8 @@ void rxe_mr_init_dma(int access, struct rxe_mr *mr);
>> int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
>> int access, struct rxe_mr *mr);
>> int rxe_mr_init_fast(int max_pages, struct rxe_mr *mr);
>> +void *rxe_map_to_vaddr(struct rxe_mr *mr, int map_index, int addr_index, size_t offset);
>> +void rxe_unmap_vaddr(struct rxe_mr *mr, void *vaddr);
>> int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
>> enum rxe_mr_copy_dir dir);
>> int copy_data(struct rxe_pd *pd, int access, struct rxe_dma_info *dma,
>> diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
>> index bc081002bddc..4246b7f34a29 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_mr.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_mr.c
>> @@ -115,13 +115,10 @@ 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;
>> int err;
>> - int i;
>>
>> umem = ib_umem_get(&rxe->ib_dev, start, length, access);
>> if (IS_ERR(umem)) {
>> @@ -144,32 +141,19 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
>>
>> mr->page_shift = PAGE_SHIFT;
>> mr->page_mask = PAGE_SIZE - 1;
>> + mr->ibmr.page_size = PAGE_SIZE;
>>
>> - num_buf = 0;
>> + num_buf = 0;
>> map = mr->map;
>> if (length > 0) {
>> - buf = map[0]->buf;
>> -
>> 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;
>> }
>>
>> - vaddr = page_address(sg_page_iter_page(&sg_iter));
>> - if (!vaddr) {
>> - pr_warn("%s: Unable to get virtual address\n",
>> - __func__);
>> - err = -ENOMEM;
>> - goto err_cleanup_map;
>> - }
>> -
>> - buf->addr = (uintptr_t)vaddr;
>> - buf->size = PAGE_SIZE;
>> + map[0]->addrs[num_buf] = (uintptr_t)sg_page_iter_page(&sg_iter);
>> num_buf++;
>> - buf++;
>> -
>> }
>> }
>>
>> @@ -181,10 +165,6 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
>>
>> return 0;
>>
>> -err_cleanup_map:
>> - for (i = 0; i < mr->num_map; i++)
>> - kfree(mr->map[i]);
>> - kfree(mr->map);
>> err_release_umem:
>> ib_umem_release(umem);
>> err_out:
>> @@ -216,9 +196,9 @@ static void lookup_iova(struct rxe_mr *mr, u64 iova, int *m_out, int *n_out,
>> size_t *offset_out)
>> {
>> size_t offset = iova - mr->ibmr.iova + mr->offset;
>> + u64 length = mr->ibmr.page_size;
>> int map_index;
>> - int buf_index;
>> - u64 length;
>> + int addr_index;
>>
>> if (likely(mr->page_shift)) {
>> *offset_out = offset & mr->page_mask;
>> @@ -227,27 +207,46 @@ static void lookup_iova(struct rxe_mr *mr, u64 iova, int *m_out, int *n_out,
>> *m_out = offset >> mr->map_shift;
>> } else {
>> map_index = 0;
>> - buf_index = 0;
>> -
>> - length = mr->map[map_index]->buf[buf_index].size;
>> + addr_index = 0;
>>
>> while (offset >= length) {
>> offset -= length;
>> - buf_index++;
>> + addr_index++;
>>
>> - if (buf_index == RXE_BUF_PER_MAP) {
>> + if (addr_index == RXE_BUF_PER_MAP) {
>> map_index++;
>> - buf_index = 0;
>> + addr_index = 0;
>> }
>> - length = mr->map[map_index]->buf[buf_index].size;
>> }
>>
>> *m_out = map_index;
>> - *n_out = buf_index;
>> + *n_out = addr_index;
>> *offset_out = offset;
>> }
>> }
>>
>> +void *rxe_map_to_vaddr(struct rxe_mr *mr, int map_index, int addr_index, size_t offset)
>> +{
>> + void *vaddr = NULL;
>> +
>> + if (mr->ibmr.type == IB_MR_TYPE_USER) {
>> + vaddr = kmap_local_page((struct page *)mr->map[map_index]->addrs[addr_index]);
>> + if (vaddr == NULL) {
>> + pr_warn("Failed to map page");
>> + return NULL;
>> + }
>> + } else
>> + vaddr = (void *)(uintptr_t)mr->map[map_index]->addrs[addr_index];
>> +
>> + return vaddr + offset;
>> +}
>> +
>> +void rxe_unmap_vaddr(struct rxe_mr *mr, void *vaddr)
>> +{
>> + if (mr->ibmr.type == IB_MR_TYPE_USER)
>> + kunmap_local(vaddr);
>> +}
>> +
>> void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length)
>> {
>> size_t offset;
>> @@ -273,13 +272,13 @@ void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length)
>>
>> lookup_iova(mr, iova, &m, &n, &offset);
>>
>> - if (offset + length > mr->map[m]->buf[n].size) {
>> + if (offset + length > mr->ibmr.page_size) {
>> pr_warn("crosses page boundary\n");
>> addr = NULL;
>> goto out;
>> }
>>
>> - addr = (void *)(uintptr_t)mr->map[m]->buf[n].addr + offset;
>> + addr = rxe_map_to_vaddr(mr, m, n, offset);
>>
>> out:
>> return addr;
>> @@ -294,8 +293,6 @@ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
>> int err;
>> int bytes;
>> u8 *va;
>> - struct rxe_map **map;
>> - struct rxe_phys_buf *buf;
>> int m;
>> int i;
>> size_t offset;
>> @@ -325,17 +322,14 @@ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
>>
>> 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;
>> + va = (u8 *)rxe_map_to_vaddr(mr, m, i, offset);
>> src = (dir == RXE_TO_MR_OBJ) ? addr : va;
>> dest = (dir == RXE_TO_MR_OBJ) ? va : addr;
>>
>> - bytes = buf->size - offset;
>> + bytes = mr->ibmr.page_size - offset;
>>
>> if (bytes > length)
>> bytes = length;
>> @@ -346,14 +340,14 @@ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
>> addr += bytes;
>>
>> offset = 0;
>> - buf++;
>> i++;
>>
>> if (i == RXE_BUF_PER_MAP) {
>> i = 0;
>> - map++;
>> - buf = map[0]->buf;
>> + m++;
>> }
>> +
>> + rxe_unmap_vaddr(mr, va);
>> }
>>
>> return 0;
>> diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
>> index c32bc12cc82f..31f9ba11a921 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_resp.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_resp.c
>> @@ -652,6 +652,7 @@ static enum resp_states atomic_reply(struct rxe_qp *qp,
>>
>> ret = RESPST_ACKNOWLEDGE;
>> out:
>> + rxe_unmap_vaddr(mr, vaddr);
>> return ret;
>> }
>>
>> diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
>> index bcdfdadaebbc..13e4d660cb02 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_verbs.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
>> @@ -948,16 +948,12 @@ static int rxe_set_page(struct ib_mr *ibmr, u64 addr)
>> {
>> struct rxe_mr *mr = to_rmr(ibmr);
>> struct rxe_map *map;
>> - struct rxe_phys_buf *buf;
>>
>> 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];
>> -
>> - buf->addr = addr;
>> - buf->size = ibmr->page_size;
>> + map->addrs[mr->nbuf % RXE_BUF_PER_MAP] = addr;
>> mr->nbuf++;
>>
>> return 0;
>> diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
>> index 22a299b0a9f0..d136f02d5b56 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_verbs.h
>> +++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
>> @@ -277,15 +277,10 @@ 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;
>> -};
>> +#define RXE_BUF_PER_MAP (PAGE_SIZE / sizeof(u64))
>>
>> struct rxe_map {
>> - struct rxe_phys_buf buf[RXE_BUF_PER_MAP];
>> + u64 addrs[RXE_BUF_PER_MAP];
>> };
>>
>> static inline int rkey_is_mw(u32 rkey)