[PATCH rdma-rc v1 0/3] ODP Fixes

[PATCH rdma-rc v1 0/3] ODP Fixes

[Leon Romanovsky]

From: Leon Romanovsky <leonro@mellanox.com>

Changelog:
 v0 -> v1: https://lore.kernel.org/linux-rdma/20191219134646.413164-1-leon@kernel.org
 * Added description of fix to patch #1
 * Added Jason's ROB tag to patch #2
 * Dropped changes in page fault handler in patch #3

-------------------------------------------------------------------------------------------
Please find below three patches that fix ODP flow.

Thanks

Artemy Kovalyov (1):
  IB/mlx5: Unify ODP MR code paths to allow extra flexibility

Yishai Hadas (2):
  IB/core: Fix ODP get user pages flow
  IB/core: Fix ODP with IB_ACCESS_HUGETLB handling

 drivers/infiniband/core/umem_odp.c   | 23 +++--------
 drivers/infiniband/hw/mlx5/mem.c     | 25 ------------
 drivers/infiniband/hw/mlx5/mlx5_ib.h |  9 ++---
 drivers/infiniband/hw/mlx5/mr.c      | 58 +++++++++++-----------------
 drivers/infiniband/hw/mlx5/odp.c     | 42 +++++++++++++++++++-
 5 files changed, 72 insertions(+), 85 deletions(-)

--
2.20.1

[PATCH rdma-rc v1 1/3] IB/mlx5: Unify ODP MR code paths to allow extra flexibility

[Leon Romanovsky]

From: Artemy Kovalyov <artemyko@mellanox.com>

Building MR translation table in ODP case requires additional flexibility,
namely random access to DMA addresses. Make both direct and indirect ODP MR
use same code path, separated from non-ODP MR code path.

This change fixed the broken __mlx5_ib_populate_pas() shift calculation.

Fixes: d2183c6f1958 ("RDMA/umem: Move page_shift from ib_umem to ib_odp_umem")
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/hw/mlx5/mem.c     | 25 ------------
 drivers/infiniband/hw/mlx5/mlx5_ib.h |  9 ++---
 drivers/infiniband/hw/mlx5/mr.c      | 58 +++++++++++-----------------
 drivers/infiniband/hw/mlx5/odp.c     | 42 +++++++++++++++++++-
 4 files changed, 67 insertions(+), 67 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/mem.c b/drivers/infiniband/hw/mlx5/mem.c
index 048f4e974a61..b90a3649e7d1 100644
--- a/drivers/infiniband/hw/mlx5/mem.c
+++ b/drivers/infiniband/hw/mlx5/mem.c
@@ -101,18 +101,6 @@ void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr,
 	*count = i;
 }
 
-static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
-{
-	u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
-
-	if (umem_dma & ODP_READ_ALLOWED_BIT)
-		mtt_entry |= MLX5_IB_MTT_READ;
-	if (umem_dma & ODP_WRITE_ALLOWED_BIT)
-		mtt_entry |= MLX5_IB_MTT_WRITE;
-
-	return mtt_entry;
-}
-
 /*
  * Populate the given array with bus addresses from the umem.
  *
@@ -139,19 +127,6 @@ void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
 	struct scatterlist *sg;
 	int entry;
 
-	if (umem->is_odp) {
-		WARN_ON(shift != 0);
-		WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
-
-		for (i = 0; i < num_pages; ++i) {
-			dma_addr_t pa =
-				to_ib_umem_odp(umem)->dma_list[offset + i];
-
-			pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
-		}
-		return;
-	}
-
 	i = 0;
 	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
 		len = sg_dma_len(sg) >> PAGE_SHIFT;
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index b06f32ff5748..927948328184 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -1276,8 +1276,8 @@ void mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev *ibdev);
 int __init mlx5_ib_odp_init(void);
 void mlx5_ib_odp_cleanup(void);
 void mlx5_odp_init_mr_cache_entry(struct mlx5_cache_ent *ent);
-void mlx5_odp_populate_klm(struct mlx5_klm *pklm, size_t offset,
-			   size_t nentries, struct mlx5_ib_mr *mr, int flags);
+void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
+			   struct mlx5_ib_mr *mr, int flags);
 
 int mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
 			       enum ib_uverbs_advise_mr_advice advice,
@@ -1293,9 +1293,8 @@ static inline void mlx5_ib_odp_cleanup_one(struct mlx5_ib_dev *ibdev) {}
 static inline int mlx5_ib_odp_init(void) { return 0; }
 static inline void mlx5_ib_odp_cleanup(void)				    {}
 static inline void mlx5_odp_init_mr_cache_entry(struct mlx5_cache_ent *ent) {}
-static inline void mlx5_odp_populate_klm(struct mlx5_klm *pklm, size_t offset,
-					 size_t nentries, struct mlx5_ib_mr *mr,
-					 int flags) {}
+static inline void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
+					 struct mlx5_ib_mr *mr, int flags) {}
 
 static inline int
 mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index ea8bfc3e2d8d..1e38ba0da16a 100644
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -868,36 +868,6 @@ static struct mlx5_ib_mr *alloc_mr_from_cache(
 	return mr;
 }
 
-static inline int populate_xlt(struct mlx5_ib_mr *mr, int idx, int npages,
-			       void *xlt, int page_shift, size_t size,
-			       int flags)
-{
-	struct mlx5_ib_dev *dev = mr->dev;
-	struct ib_umem *umem = mr->umem;
-
-	if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
-		if (!umr_can_use_indirect_mkey(dev))
-			return -EPERM;
-		mlx5_odp_populate_klm(xlt, idx, npages, mr, flags);
-		return npages;
-	}
-
-	npages = min_t(size_t, npages, ib_umem_num_pages(umem) - idx);
-
-	if (!(flags & MLX5_IB_UPD_XLT_ZAP)) {
-		__mlx5_ib_populate_pas(dev, umem, page_shift,
-				       idx, npages, xlt,
-				       MLX5_IB_MTT_PRESENT);
-		/* Clear padding after the pages
-		 * brought from the umem.
-		 */
-		memset(xlt + (npages * sizeof(struct mlx5_mtt)), 0,
-		       size - npages * sizeof(struct mlx5_mtt));
-	}
-
-	return npages;
-}
-
 #define MLX5_MAX_UMR_CHUNK ((1 << (MLX5_MAX_UMR_SHIFT + 4)) - \
 			    MLX5_UMR_MTT_ALIGNMENT)
 #define MLX5_SPARE_UMR_CHUNK 0x10000
@@ -921,6 +891,7 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages,
 	size_t pages_mapped = 0;
 	size_t pages_to_map = 0;
 	size_t pages_iter = 0;
+	size_t size_to_map = 0;
 	gfp_t gfp;
 	bool use_emergency_page = false;
 
@@ -967,6 +938,15 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages,
 		goto free_xlt;
 	}
 
+	if (mr->umem->is_odp) {
+		if (!(flags & MLX5_IB_UPD_XLT_INDIRECT)) {
+			struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+			size_t max_pages = ib_umem_odp_num_pages(odp) - idx;
+
+			pages_to_map = min_t(size_t, pages_to_map, max_pages);
+		}
+	}
+
 	sg.addr = dma;
 	sg.lkey = dev->umrc.pd->local_dma_lkey;
 
@@ -989,14 +969,22 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages,
 	     pages_mapped < pages_to_map && !err;
 	     pages_mapped += pages_iter, idx += pages_iter) {
 		npages = min_t(int, pages_iter, pages_to_map - pages_mapped);
+		size_to_map = npages * desc_size;
 		dma_sync_single_for_cpu(ddev, dma, size, DMA_TO_DEVICE);
-		npages = populate_xlt(mr, idx, npages, xlt,
-				      page_shift, size, flags);
-
+		if (mr->umem->is_odp) {
+			mlx5_odp_populate_xlt(xlt, idx, npages, mr, flags);
+		} else {
+			__mlx5_ib_populate_pas(dev, mr->umem, page_shift, idx,
+					       npages, xlt,
+					       MLX5_IB_MTT_PRESENT);
+			/* Clear padding after the pages
+			 * brought from the umem.
+			 */
+			memset(xlt + size_to_map, 0, size - size_to_map);
+		}
 		dma_sync_single_for_device(ddev, dma, size, DMA_TO_DEVICE);
 
-		sg.length = ALIGN(npages * desc_size,
-				  MLX5_UMR_MTT_ALIGNMENT);
+		sg.length = ALIGN(size_to_map, MLX5_UMR_MTT_ALIGNMENT);
 
 		if (pages_mapped + pages_iter >= pages_to_map) {
 			if (flags & MLX5_IB_UPD_XLT_ENABLE)
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index f924250f80c2..92da6c4f7ddd 100644
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -93,8 +93,8 @@ struct mlx5_pagefault {
 
 static u64 mlx5_imr_ksm_entries;
 
-void mlx5_odp_populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
-			   struct mlx5_ib_mr *imr, int flags)
+static void populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
+			struct mlx5_ib_mr *imr, int flags)
 {
 	struct mlx5_klm *end = pklm + nentries;
 
@@ -144,6 +144,44 @@ void mlx5_odp_populate_klm(struct mlx5_klm *pklm, size_t idx, size_t nentries,
 	}
 }
 
+static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
+{
+	u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
+
+	if (umem_dma & ODP_READ_ALLOWED_BIT)
+		mtt_entry |= MLX5_IB_MTT_READ;
+	if (umem_dma & ODP_WRITE_ALLOWED_BIT)
+		mtt_entry |= MLX5_IB_MTT_WRITE;
+
+	return mtt_entry;
+}
+
+static void populate_mtt(__be64 *pas, size_t idx, size_t nentries,
+			 struct mlx5_ib_mr *mr, int flags)
+{
+	struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
+	dma_addr_t pa;
+	size_t i;
+
+	if (flags & MLX5_IB_UPD_XLT_ZAP)
+		return;
+
+	for (i = 0; i < nentries; i++) {
+		pa = odp->dma_list[idx + i];
+		pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
+	}
+}
+
+void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
+			   struct mlx5_ib_mr *mr, int flags)
+{
+	if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
+		populate_klm(xlt, idx, nentries, mr, flags);
+	} else {
+		populate_mtt(xlt, idx, nentries, mr, flags);
+	}
+}
+
 static void dma_fence_odp_mr(struct mlx5_ib_mr *mr)
 {
 	struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
-- 
2.20.1

[PATCH rdma-rc v1 2/3] IB/core: Fix ODP get user pages flow

[Leon Romanovsky]

From: Yishai Hadas <yishaih@mellanox.com>

When calling get_user_pages_remote() need to work with granularity of
PAGE_SIZE.

Fix the calculation of how many entries can be read in one call to
consider that.

Fixes: 403cd12e2cf7 ("IB/umem: Add contiguous ODP support")
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/core/umem_odp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index e42d44e501fd..2e9ee7adab13 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -440,7 +440,7 @@ int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 user_virt,
 
 	while (bcnt > 0) {
 		const size_t gup_num_pages = min_t(size_t,
-				(bcnt + BIT(page_shift) - 1) >> page_shift,
+				ALIGN(bcnt, PAGE_SIZE) / PAGE_SIZE,
 				PAGE_SIZE / sizeof(struct page *));
 
 		down_read(&owning_mm->mmap_sem);
-- 
2.20.1

[PATCH rdma-rc v1 3/3] IB/core: Fix ODP with IB_ACCESS_HUGETLB handling

[Leon Romanovsky]

From: Yishai Hadas <yishaih@mellanox.com>

As VMAs for a given range might not be available as part of the
registration phase in ODP.

ib_init_umem_odp() considered the expected page shift value that was
previously set and initializes its internals accordingly.

If memory doesn't backed by physical contiguous pages aligned to
hugepage boundary an error will be set as part of the page fault flow
once be detected.

Fixes: 0008b84ea9af ("IB/umem: Add support to huge ODP")
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/core/umem_odp.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index 2e9ee7adab13..f42fa31c24a2 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -241,22 +241,10 @@ struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr,
 	umem_odp->umem.owning_mm = mm = current->mm;
 	umem_odp->notifier.ops = ops;
 
-	umem_odp->page_shift = PAGE_SHIFT;
-	if (access & IB_ACCESS_HUGETLB) {
-		struct vm_area_struct *vma;
-		struct hstate *h;
-
-		down_read(&mm->mmap_sem);
-		vma = find_vma(mm, ib_umem_start(umem_odp));
-		if (!vma || !is_vm_hugetlb_page(vma)) {
-			up_read(&mm->mmap_sem);
-			ret = -EINVAL;
-			goto err_free;
-		}
-		h = hstate_vma(vma);
-		umem_odp->page_shift = huge_page_shift(h);
-		up_read(&mm->mmap_sem);
-	}
+	if (access & IB_ACCESS_HUGETLB)
+		umem_odp->page_shift = HPAGE_SHIFT;
+	else
+		umem_odp->page_shift = PAGE_SHIFT;
 
 	umem_odp->tgid = get_task_pid(current->group_leader, PIDTYPE_PID);
 	ret = ib_init_umem_odp(umem_odp, ops);
@@ -266,7 +254,6 @@ struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr,
 
 err_put_pid:
 	put_pid(umem_odp->tgid);
-err_free:
 	kfree(umem_odp);
 	return ERR_PTR(ret);
 }
-- 
2.20.1

Re: [PATCH rdma-rc v1 0/3] ODP Fixes

[Jason Gunthorpe]

On Sun, Dec 22, 2019 at 02:46:46PM +0200, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@mellanox.com>
> 
> Changelog:
>  v0 -> v1: https://lore.kernel.org/linux-rdma/20191219134646.413164-1-leon@kernel.org
>  * Added description of fix to patch #1
>  * Added Jason's ROB tag to patch #2
>  * Dropped changes in page fault handler in patch #3
> 
> Please find below three patches that fix ODP flow.

Applied to for-next, not rc
 
> Artemy Kovalyov (1):
>   IB/mlx5: Unify ODP MR code paths to allow extra flexibility

This is the only one that really fixes a bug, and it is too big for
rc5 at this point.
 
> Yishai Hadas (2):
>   IB/core: Fix ODP get user pages flow
>   IB/core: Fix ODP with IB_ACCESS_HUGETLB handling

While these are needed fixes they are not bugs...

Thanks,
Jason