| Message ID | 1603471201-32588-5-git-send-email-jianxin.xiong@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | RDMA: Add dma-buf support | expand |
On Fri, Oct 23, 2020 at 09:40:01AM -0700, Jianxin Xiong wrote: > diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c > index b261797..3bc412b 100644 > +++ b/drivers/infiniband/hw/mlx5/mr.c > @@ -1,5 +1,6 @@ > /* > * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved. > + * Copyright (c) 2020, Intel Corporation. All rights reserved. > * > * This software is available to you under a choice of one of two > * licenses. You may choose to be licensed under the terms of the GNU > @@ -36,6 +37,8 @@ > #include <linux/debugfs.h> > #include <linux/export.h> > #include <linux/delay.h> > +#include <linux/dma-buf.h> > +#include <linux/dma-resv.h> > #include <rdma/ib_umem.h> > #include <rdma/ib_umem_odp.h> > #include <rdma/ib_verbs.h> > @@ -1113,6 +1116,8 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages, > dma_sync_single_for_cpu(ddev, dma, size, DMA_TO_DEVICE); > if (mr->umem->is_odp) { > mlx5_odp_populate_xlt(xlt, idx, npages, mr, flags); > + } else if (mr->umem->is_dmabuf && (flags & MLX5_IB_UPD_XLT_ZAP)) { > + memset(xlt, 0, size); > } else { > __mlx5_ib_populate_pas(dev, mr->umem, page_shift, idx, > npages, xlt, > @@ -1462,6 +1467,111 @@ struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length, > return ERR_PTR(err); > } > > +static void mlx5_ib_dmabuf_invalidate_cb(struct dma_buf_attachment *attach) > +{ > + struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv; > + struct mlx5_ib_mr *mr = umem_dmabuf->device_context; > + > + mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, MLX5_IB_UPD_XLT_ZAP); > + ib_umem_dmabuf_unmap_pages(umem_dmabuf); > +} > + > +static struct dma_buf_attach_ops mlx5_ib_dmabuf_attach_ops = { > + .allow_peer2peer = 1, > + .move_notify = mlx5_ib_dmabuf_invalidate_cb, > +}; > + > +struct ib_mr *mlx5_ib_reg_user_mr_dmabuf(struct ib_pd *pd, u64 offset, > + u64 length, u64 virt_addr, > + int fd, int access_flags, > + struct ib_udata *udata) > +{ > + struct mlx5_ib_dev *dev = to_mdev(pd->device); > + struct mlx5_ib_mr *mr = NULL; > + struct ib_umem *umem; > + struct ib_umem_dmabuf *umem_dmabuf; > + int npages; > + int order; > + int err; > + > + if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM)) > + return ERR_PTR(-EOPNOTSUPP); > + > + mlx5_ib_dbg(dev, > + "offset 0x%llx, virt_addr 0x%llx, length 0x%llx, fd %d, access_flags 0x%x\n", > + offset, virt_addr, length, fd, access_flags); > + > + if (!mlx5_ib_can_load_pas_with_umr(dev, length)) > + return ERR_PTR(-EINVAL); > + > + umem = ib_umem_dmabuf_get(&dev->ib_dev, offset, length, fd, access_flags, > + &mlx5_ib_dmabuf_attach_ops); > + if (IS_ERR(umem)) { > + mlx5_ib_dbg(dev, "umem get failed (%ld)\n", PTR_ERR(umem)); > + return ERR_PTR(PTR_ERR(umem)); > + } > + > + npages = ib_umem_num_pages(umem); > + if (!npages) { ib_umem_get should reject invalid umems like this > + mlx5_ib_warn(dev, "avoid zero region\n"); > + ib_umem_release(umem); > + return ERR_PTR(-EINVAL); > + } > + > + order = ilog2(roundup_pow_of_two(npages)); Must always call ib_umem_find_best_pgsz(), specify PAGE_SIZE as the argument for this scenario > + mlx5_ib_dbg(dev, "npages %d, ncont %d, order %d, page_shift %d\n", > + npages, npages, order, PAGE_SHIFT); > + > + mr = alloc_mr_from_cache(pd, umem, virt_addr, length, npages, > + PAGE_SHIFT, order, access_flags); > + if (IS_ERR(mr)) > + mr = NULL; > + > + if (!mr) { > + mutex_lock(&dev->slow_path_mutex); > + mr = reg_create(NULL, pd, virt_addr, length, umem, npages, > + PAGE_SHIFT, access_flags, false); > + mutex_unlock(&dev->slow_path_mutex); > + } Rebase on the mlx5 series just posted and use their version of this code sequence, this is just not quite right > + err = mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, > + MLX5_IB_UPD_XLT_ENABLE | MLX5_IB_UPD_XLT_ZAP); > + > + if (err) { > + dereg_mr(dev, mr); > + return ERR_PTR(err); > + } The current mlx5 code preloads the buffer with the right data, zapping is fairly expensive, mapping and loading is the same cost > @@ -1536,7 +1646,7 @@ int mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start, > if (!mr->umem) > return -EINVAL; > > - if (is_odp_mr(mr)) > + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) > return -EOPNOTSUPP; > > if (flags & IB_MR_REREG_TRANS) { > @@ -1695,7 +1805,7 @@ static void dereg_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr) > struct ib_umem *umem = mr->umem; > > /* Stop all DMA */ > - if (is_odp_mr(mr)) > + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) > mlx5_ib_fence_odp_mr(mr); Make a dma buf specific function I have another series touching this area too, but I think > @@ -801,6 +816,52 @@ static int pagefault_implicit_mr(struct mlx5_ib_mr *imr, > * Returns: > * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are > * not accessible, or the MR is no longer valid. > + * -EAGAIN: The operation should be retried > + * > + * >0: Number of pages mapped > + */ > +static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, struct ib_umem *umem, > + u64 io_virt, size_t bcnt, u32 *bytes_mapped, > + u32 flags) > +{ > + struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(umem); > + u64 user_va; > + u64 end; > + int npages; > + int err; > + > + if (unlikely(io_virt < mr->mmkey.iova)) > + return -EFAULT; > + if (check_add_overflow(io_virt - mr->mmkey.iova, > + (u64)umem->address, &user_va)) > + return -EFAULT; > + /* Overflow has alreddy been checked at the umem creation time */ > + end = umem->address + umem->length; > + if (unlikely(user_va >= end || end - user_va < bcnt)) > + return -EFAULT; Why duplicate this sequence? Caller does it > @@ -811,6 +872,10 @@ static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt, > { > struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem); > > + if (is_dmabuf_mr(mr)) > + return pagefault_dmabuf_mr(mr, mr->umem, io_virt, bcnt, > + bytes_mapped, flags); > + > lockdep_assert_held(&mr->dev->odp_srcu); > if (unlikely(io_virt < mr->mmkey.iova)) > return -EFAULT; > @@ -1747,7 +1812,6 @@ static void destroy_prefetch_work(struct prefetch_mr_work *work) > { > struct mlx5_ib_dev *dev = to_mdev(pd->device); > struct mlx5_core_mkey *mmkey; > - struct ib_umem_odp *odp; > struct mlx5_ib_mr *mr; > > lockdep_assert_held(&dev->odp_srcu); > @@ -1761,11 +1825,9 @@ static void destroy_prefetch_work(struct prefetch_mr_work *work) > if (mr->ibmr.pd != pd) > return NULL; > > - odp = to_ib_umem_odp(mr->umem); > - > /* prefetch with write-access must be supported by the MR */ > if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE && > - !odp->umem.writable) > + !mr->umem->writable) ?? This does look basically right though. I think a little more polishing and it can be merged. It does need to go after the mlx5 MR series though.. Jason
> -----Original Message----- > From: Jason Gunthorpe <jgg@ziepe.ca> > Sent: Tuesday, October 27, 2020 1:08 PM > To: Xiong, Jianxin <jianxin.xiong@intel.com> > Cc: linux-rdma@vger.kernel.org; dri-devel@lists.freedesktop.org; Doug Ledford <dledford@redhat.com>; Leon Romanovsky > <leon@kernel.org>; Sumit Semwal <sumit.semwal@linaro.org>; Christian Koenig <christian.koenig@amd.com>; Vetter, Daniel > <daniel.vetter@intel.com> > Subject: Re: [PATCH v6 4/4] RDMA/mlx5: Support dma-buf based userspace memory region > > On Fri, Oct 23, 2020 at 09:40:01AM -0700, Jianxin Xiong wrote: > > > diff --git a/drivers/infiniband/hw/mlx5/mr.c > > b/drivers/infiniband/hw/mlx5/mr.c index b261797..3bc412b 100644 > > +++ b/drivers/infiniband/hw/mlx5/mr.c > > @@ -1,5 +1,6 @@ > > /* > > * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved. > > + * Copyright (c) 2020, Intel Corporation. All rights reserved. > > * > > * This software is available to you under a choice of one of two > > * licenses. You may choose to be licensed under the terms of the > > GNU @@ -36,6 +37,8 @@ #include <linux/debugfs.h> #include > > <linux/export.h> #include <linux/delay.h> > > +#include <linux/dma-buf.h> > > +#include <linux/dma-resv.h> > > #include <rdma/ib_umem.h> > > #include <rdma/ib_umem_odp.h> > > #include <rdma/ib_verbs.h> > > @@ -1113,6 +1116,8 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages, > > dma_sync_single_for_cpu(ddev, dma, size, DMA_TO_DEVICE); > > if (mr->umem->is_odp) { > > mlx5_odp_populate_xlt(xlt, idx, npages, mr, flags); > > + } else if (mr->umem->is_dmabuf && (flags & MLX5_IB_UPD_XLT_ZAP)) { > > + memset(xlt, 0, size); > > } else { > > __mlx5_ib_populate_pas(dev, mr->umem, page_shift, idx, > > npages, xlt, > > @@ -1462,6 +1467,111 @@ struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length, > > return ERR_PTR(err); > > } > > > > +static void mlx5_ib_dmabuf_invalidate_cb(struct dma_buf_attachment > > +*attach) { > > + struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv; > > + struct mlx5_ib_mr *mr = umem_dmabuf->device_context; > > + > > + mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, MLX5_IB_UPD_XLT_ZAP); > > + ib_umem_dmabuf_unmap_pages(umem_dmabuf); > > +} > > + > > +static struct dma_buf_attach_ops mlx5_ib_dmabuf_attach_ops = { > > + .allow_peer2peer = 1, > > + .move_notify = mlx5_ib_dmabuf_invalidate_cb, }; > > + > > +struct ib_mr *mlx5_ib_reg_user_mr_dmabuf(struct ib_pd *pd, u64 offset, > > + u64 length, u64 virt_addr, > > + int fd, int access_flags, > > + struct ib_udata *udata) > > +{ > > + struct mlx5_ib_dev *dev = to_mdev(pd->device); > > + struct mlx5_ib_mr *mr = NULL; > > + struct ib_umem *umem; > > + struct ib_umem_dmabuf *umem_dmabuf; > > + int npages; > > + int order; > > + int err; > > + > > + if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM)) > > + return ERR_PTR(-EOPNOTSUPP); > > + > > + mlx5_ib_dbg(dev, > > + "offset 0x%llx, virt_addr 0x%llx, length 0x%llx, fd %d, access_flags 0x%x\n", > > + offset, virt_addr, length, fd, access_flags); > > + > > + if (!mlx5_ib_can_load_pas_with_umr(dev, length)) > > + return ERR_PTR(-EINVAL); > > + > > + umem = ib_umem_dmabuf_get(&dev->ib_dev, offset, length, fd, access_flags, > > + &mlx5_ib_dmabuf_attach_ops); > > + if (IS_ERR(umem)) { > > + mlx5_ib_dbg(dev, "umem get failed (%ld)\n", PTR_ERR(umem)); > > + return ERR_PTR(PTR_ERR(umem)); > > + } > > + > > + npages = ib_umem_num_pages(umem); > > + if (!npages) { > > ib_umem_get should reject invalid umems like this Will move the check to ib_umem_dmabuf_get(). > > > + mlx5_ib_warn(dev, "avoid zero region\n"); > > + ib_umem_release(umem); > > + return ERR_PTR(-EINVAL); > > + } > > + > > + order = ilog2(roundup_pow_of_two(npages)); > > Must always call ib_umem_find_best_pgsz(), specify PAGE_SIZE as the argument for this scenario Will fix. > > > + mlx5_ib_dbg(dev, "npages %d, ncont %d, order %d, page_shift %d\n", > > + npages, npages, order, PAGE_SHIFT); > > + > > + mr = alloc_mr_from_cache(pd, umem, virt_addr, length, npages, > > + PAGE_SHIFT, order, access_flags); > > + if (IS_ERR(mr)) > > + mr = NULL; > > + > > + if (!mr) { > > + mutex_lock(&dev->slow_path_mutex); > > + mr = reg_create(NULL, pd, virt_addr, length, umem, npages, > > + PAGE_SHIFT, access_flags, false); > > + mutex_unlock(&dev->slow_path_mutex); > > + } > > Rebase on the mlx5 series just posted and use their version of this code sequence, this is just not quite right Will do. > > > > + err = mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, > > + MLX5_IB_UPD_XLT_ENABLE | MLX5_IB_UPD_XLT_ZAP); > > + > > + if (err) { > > + dereg_mr(dev, mr); > > + return ERR_PTR(err); > > + } > > The current mlx5 code preloads the buffer with the right data, zapping is fairly expensive, mapping and loading is the same cost Could probably do the same here. Will double check. > > > @@ -1536,7 +1646,7 @@ int mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start, > > if (!mr->umem) > > return -EINVAL; > > > > - if (is_odp_mr(mr)) > > + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) > > return -EOPNOTSUPP; > > > > if (flags & IB_MR_REREG_TRANS) { > > @@ -1695,7 +1805,7 @@ static void dereg_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr) > > struct ib_umem *umem = mr->umem; > > > > /* Stop all DMA */ > > - if (is_odp_mr(mr)) > > + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) > > mlx5_ib_fence_odp_mr(mr); > > Make a dma buf specific function Ok. > > I have another series touching this area too, but I think > > > @@ -801,6 +816,52 @@ static int pagefault_implicit_mr(struct mlx5_ib_mr *imr, > > * Returns: > > * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are > > * not accessible, or the MR is no longer valid. > > + * -EAGAIN: The operation should be retried > > + * > > + * >0: Number of pages mapped > > + */ > > +static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, struct ib_umem *umem, > > + u64 io_virt, size_t bcnt, u32 *bytes_mapped, > > + u32 flags) > > +{ > > + struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(umem); > > + u64 user_va; > > + u64 end; > > + int npages; > > + int err; > > + > > + if (unlikely(io_virt < mr->mmkey.iova)) > > + return -EFAULT; > > + if (check_add_overflow(io_virt - mr->mmkey.iova, > > + (u64)umem->address, &user_va)) > > + return -EFAULT; > > + /* Overflow has alreddy been checked at the umem creation time */ > > + end = umem->address + umem->length; > > + if (unlikely(user_va >= end || end - user_va < bcnt)) > > + return -EFAULT; > > Why duplicate this sequence? Caller does it The sequence in the caller is for umem_odp only. > > > @@ -811,6 +872,10 @@ static int pagefault_mr(struct mlx5_ib_mr *mr, > > u64 io_virt, size_t bcnt, { > > struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem); > > > > + if (is_dmabuf_mr(mr)) > > + return pagefault_dmabuf_mr(mr, mr->umem, io_virt, bcnt, > > + bytes_mapped, flags); > > + > > lockdep_assert_held(&mr->dev->odp_srcu); > > if (unlikely(io_virt < mr->mmkey.iova)) > > return -EFAULT; > > @@ -1747,7 +1812,6 @@ static void destroy_prefetch_work(struct > > prefetch_mr_work *work) { > > struct mlx5_ib_dev *dev = to_mdev(pd->device); > > struct mlx5_core_mkey *mmkey; > > - struct ib_umem_odp *odp; > > struct mlx5_ib_mr *mr; > > > > lockdep_assert_held(&dev->odp_srcu); > > @@ -1761,11 +1825,9 @@ static void destroy_prefetch_work(struct prefetch_mr_work *work) > > if (mr->ibmr.pd != pd) > > return NULL; > > > > - odp = to_ib_umem_odp(mr->umem); > > - > > /* prefetch with write-access must be supported by the MR */ > > if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE && > > - !odp->umem.writable) > > + !mr->umem->writable) > > ?? There is no need to use umem_odp here, mr->umem is the same as &odp->umem. This change makes the code works for both umem_odp and umem_dmabuf. > > This does look basically right though. I think a little more polishing and it can be merged. It does need to go after the mlx5 MR series > though.. > > Jason
On Tue, Oct 27, 2020 at 08:33:52PM +0000, Xiong, Jianxin wrote: > > > @@ -801,6 +816,52 @@ static int pagefault_implicit_mr(struct mlx5_ib_mr *imr, > > > * Returns: > > > * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are > > > * not accessible, or the MR is no longer valid. > > > + * -EAGAIN: The operation should be retried > > > + * > > > + * >0: Number of pages mapped > > > + */ > > > +static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, struct ib_umem *umem, > > > + u64 io_virt, size_t bcnt, u32 *bytes_mapped, > > > + u32 flags) > > > +{ > > > + struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(umem); > > > + u64 user_va; > > > + u64 end; > > > + int npages; > > > + int err; > > > + > > > + if (unlikely(io_virt < mr->mmkey.iova)) > > > + return -EFAULT; > > > + if (check_add_overflow(io_virt - mr->mmkey.iova, > > > + (u64)umem->address, &user_va)) > > > + return -EFAULT; > > > + /* Overflow has alreddy been checked at the umem creation time */ > > > + end = umem->address + umem->length; > > > + if (unlikely(user_va >= end || end - user_va < bcnt)) > > > + return -EFAULT; > > > > Why duplicate this sequence? Caller does it > > The sequence in the caller is for umem_odp only. Nothing about umem_odp in this code though?? > > > /* prefetch with write-access must be supported by the MR */ > > > if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE && > > > - !odp->umem.writable) > > > + !mr->umem->writable) > > > > ?? > There is no need to use umem_odp here, mr->umem is the same as &odp->umem. > This change makes the code works for both umem_odp and umem_dmabuf. Ok Can you please also think about how to test this? I very much prefer to see new pyverbs tests for new APIs. Distros are running the rdma-core test suite, if you want this to work widely we need a public test for it. Thanks, Jason
> -----Original Message----- > From: Jason Gunthorpe <jgg@ziepe.ca> > Sent: Wednesday, October 28, 2020 9:36 AM > To: Xiong, Jianxin <jianxin.xiong@intel.com> > Cc: linux-rdma@vger.kernel.org; dri-devel@lists.freedesktop.org; Doug Ledford <dledford@redhat.com>; Leon Romanovsky > <leon@kernel.org>; Sumit Semwal <sumit.semwal@linaro.org>; Christian Koenig <christian.koenig@amd.com>; Vetter, Daniel > <daniel.vetter@intel.com> > Subject: Re: [PATCH v6 4/4] RDMA/mlx5: Support dma-buf based userspace memory region > > On Tue, Oct 27, 2020 at 08:33:52PM +0000, Xiong, Jianxin wrote: > > > > @@ -801,6 +816,52 @@ static int pagefault_implicit_mr(struct mlx5_ib_mr *imr, > > > > * Returns: > > > > * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are > > > > * not accessible, or the MR is no longer valid. > > > > + * -EAGAIN: The operation should be retried > > > > + * > > > > + * >0: Number of pages mapped > > > > + */ > > > > +static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, struct ib_umem *umem, > > > > + u64 io_virt, size_t bcnt, u32 *bytes_mapped, > > > > + u32 flags) > > > > +{ > > > > + struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(umem); > > > > + u64 user_va; > > > > + u64 end; > > > > + int npages; > > > > + int err; > > > > + > > > > + if (unlikely(io_virt < mr->mmkey.iova)) > > > > + return -EFAULT; > > > > + if (check_add_overflow(io_virt - mr->mmkey.iova, > > > > + (u64)umem->address, &user_va)) > > > > + return -EFAULT; > > > > + /* Overflow has alreddy been checked at the umem creation time */ > > > > + end = umem->address + umem->length; > > > > + if (unlikely(user_va >= end || end - user_va < bcnt)) > > > > + return -EFAULT; > > > > > > Why duplicate this sequence? Caller does it > > > > The sequence in the caller is for umem_odp only. > > Nothing about umem_odp in this code though?? The code in the caller uses ib_umem_end(odp) instead of the 'end' here, but we can consolidate that with some minor changes. > > > > > /* prefetch with write-access must be supported by the MR */ > > > > if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE && > > > > - !odp->umem.writable) > > > > + !mr->umem->writable) > > > > > > ?? > > > There is no need to use umem_odp here, mr->umem is the same as &odp->umem. > > This change makes the code works for both umem_odp and umem_dmabuf. > > Ok > > Can you please also think about how to test this? I very much prefer to see new pyverbs tests for new APIs. > > Distros are running the rdma-core test suite, if you want this to work widely we need a public test for it. > Will look into that. > Thanks, > Jason
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index 89e04ca..ec4ad2f 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB /* * Copyright (c) 2013-2020, Mellanox Technologies inc. All rights reserved. + * Copyright (c) 2020, Intel Corporation. All rights reserved. */ #include <linux/debugfs.h> @@ -4060,6 +4061,7 @@ static int mlx5_ib_enable_driver(struct ib_device *dev) .query_srq = mlx5_ib_query_srq, .query_ucontext = mlx5_ib_query_ucontext, .reg_user_mr = mlx5_ib_reg_user_mr, + .reg_user_mr_dmabuf = mlx5_ib_reg_user_mr_dmabuf, .req_notify_cq = mlx5_ib_arm_cq, .rereg_user_mr = mlx5_ib_rereg_user_mr, .resize_cq = mlx5_ib_resize_cq, diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h index b1f2b34..4b72ff9 100644 --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h @@ -1,6 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */ /* * Copyright (c) 2013-2020, Mellanox Technologies inc. All rights reserved. + * Copyright (c) 2020, Intel Corporation. All rights reserved. */ #ifndef MLX5_IB_H @@ -639,6 +640,12 @@ static inline bool is_odp_mr(struct mlx5_ib_mr *mr) mr->umem->is_odp; } +static inline bool is_dmabuf_mr(struct mlx5_ib_mr *mr) +{ + return IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING) && mr->umem && + mr->umem->is_dmabuf; +} + struct mlx5_ib_mw { struct ib_mw ibmw; struct mlx5_core_mkey mmkey; @@ -1174,6 +1181,10 @@ int mlx5_ib_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr, struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length, u64 virt_addr, int access_flags, struct ib_udata *udata); +struct ib_mr *mlx5_ib_reg_user_mr_dmabuf(struct ib_pd *pd, u64 start, + u64 length, u64 virt_addr, + int fd, int access_flags, + struct ib_udata *udata); int mlx5_ib_advise_mr(struct ib_pd *pd, enum ib_uverbs_advise_mr_advice advice, u32 flags, diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c index b261797..3bc412b 100644 --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1,5 +1,6 @@ /* * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved. + * Copyright (c) 2020, Intel Corporation. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU @@ -36,6 +37,8 @@ #include <linux/debugfs.h> #include <linux/export.h> #include <linux/delay.h> +#include <linux/dma-buf.h> +#include <linux/dma-resv.h> #include <rdma/ib_umem.h> #include <rdma/ib_umem_odp.h> #include <rdma/ib_verbs.h> @@ -1113,6 +1116,8 @@ int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages, dma_sync_single_for_cpu(ddev, dma, size, DMA_TO_DEVICE); if (mr->umem->is_odp) { mlx5_odp_populate_xlt(xlt, idx, npages, mr, flags); + } else if (mr->umem->is_dmabuf && (flags & MLX5_IB_UPD_XLT_ZAP)) { + memset(xlt, 0, size); } else { __mlx5_ib_populate_pas(dev, mr->umem, page_shift, idx, npages, xlt, @@ -1462,6 +1467,111 @@ struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length, return ERR_PTR(err); } +static void mlx5_ib_dmabuf_invalidate_cb(struct dma_buf_attachment *attach) +{ + struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv; + struct mlx5_ib_mr *mr = umem_dmabuf->device_context; + + mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, MLX5_IB_UPD_XLT_ZAP); + ib_umem_dmabuf_unmap_pages(umem_dmabuf); +} + +static struct dma_buf_attach_ops mlx5_ib_dmabuf_attach_ops = { + .allow_peer2peer = 1, + .move_notify = mlx5_ib_dmabuf_invalidate_cb, +}; + +struct ib_mr *mlx5_ib_reg_user_mr_dmabuf(struct ib_pd *pd, u64 offset, + u64 length, u64 virt_addr, + int fd, int access_flags, + struct ib_udata *udata) +{ + struct mlx5_ib_dev *dev = to_mdev(pd->device); + struct mlx5_ib_mr *mr = NULL; + struct ib_umem *umem; + struct ib_umem_dmabuf *umem_dmabuf; + int npages; + int order; + int err; + + if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM)) + return ERR_PTR(-EOPNOTSUPP); + + mlx5_ib_dbg(dev, + "offset 0x%llx, virt_addr 0x%llx, length 0x%llx, fd %d, access_flags 0x%x\n", + offset, virt_addr, length, fd, access_flags); + + if (!mlx5_ib_can_load_pas_with_umr(dev, length)) + return ERR_PTR(-EINVAL); + + umem = ib_umem_dmabuf_get(&dev->ib_dev, offset, length, fd, access_flags, + &mlx5_ib_dmabuf_attach_ops); + if (IS_ERR(umem)) { + mlx5_ib_dbg(dev, "umem get failed (%ld)\n", PTR_ERR(umem)); + return ERR_PTR(PTR_ERR(umem)); + } + + npages = ib_umem_num_pages(umem); + if (!npages) { + mlx5_ib_warn(dev, "avoid zero region\n"); + ib_umem_release(umem); + return ERR_PTR(-EINVAL); + } + + order = ilog2(roundup_pow_of_two(npages)); + + mlx5_ib_dbg(dev, "npages %d, ncont %d, order %d, page_shift %d\n", + npages, npages, order, PAGE_SHIFT); + + mr = alloc_mr_from_cache(pd, umem, virt_addr, length, npages, + PAGE_SHIFT, order, access_flags); + if (IS_ERR(mr)) + mr = NULL; + + if (!mr) { + mutex_lock(&dev->slow_path_mutex); + mr = reg_create(NULL, pd, virt_addr, length, umem, npages, + PAGE_SHIFT, access_flags, false); + mutex_unlock(&dev->slow_path_mutex); + } + + if (IS_ERR(mr)) { + err = PTR_ERR(mr); + goto error; + } + + mlx5_ib_dbg(dev, "mkey 0x%x\n", mr->mmkey.key); + + mr->umem = umem; + set_mr_fields(dev, mr, npages, length, access_flags); + + umem_dmabuf = to_ib_umem_dmabuf(umem); + umem_dmabuf->device_context = mr; + + err = mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, + MLX5_IB_UPD_XLT_ENABLE | MLX5_IB_UPD_XLT_ZAP); + + if (err) { + dereg_mr(dev, mr); + return ERR_PTR(err); + } + + init_waitqueue_head(&mr->q_deferred_work); + atomic_set(&mr->num_deferred_work, 0); + err = xa_err(xa_store(&dev->odp_mkeys, + mlx5_base_mkey(mr->mmkey.key), &mr->mmkey, + GFP_KERNEL)); + if (err) { + dereg_mr(dev, mr); + return ERR_PTR(err); + } + + return &mr->ibmr; +error: + ib_umem_release(umem); + return ERR_PTR(err); +} + /** * mlx5_mr_cache_invalidate - Fence all DMA on the MR * @mr: The MR to fence @@ -1536,7 +1646,7 @@ int mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start, if (!mr->umem) return -EINVAL; - if (is_odp_mr(mr)) + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) return -EOPNOTSUPP; if (flags & IB_MR_REREG_TRANS) { @@ -1695,7 +1805,7 @@ static void dereg_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr) struct ib_umem *umem = mr->umem; /* Stop all DMA */ - if (is_odp_mr(mr)) + if (is_odp_mr(mr) || is_dmabuf_mr(mr)) mlx5_ib_fence_odp_mr(mr); else clean_mr(dev, mr); diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c index 5c853ec..7bc863b 100644 --- a/drivers/infiniband/hw/mlx5/odp.c +++ b/drivers/infiniband/hw/mlx5/odp.c @@ -33,6 +33,8 @@ #include <rdma/ib_umem.h> #include <rdma/ib_umem_odp.h> #include <linux/kernel.h> +#include <linux/dma-buf.h> +#include <linux/dma-resv.h> #include "mlx5_ib.h" #include "cmd.h" @@ -204,6 +206,16 @@ static void dma_fence_odp_mr(struct mlx5_ib_mr *mr) } } +static void dma_fence_dmabuf_mr(struct mlx5_ib_mr *mr) +{ + mlx5_mr_cache_invalidate(mr); + + if (!mr->cache_ent) { + mlx5_core_destroy_mkey(mr->dev->mdev, &mr->mmkey); + WARN_ON(mr->descs); + } +} + /* * This must be called after the mr has been removed from implicit_children * and the SRCU synchronized. NOTE: The MR does not necessarily have to be @@ -661,6 +673,9 @@ void mlx5_ib_fence_odp_mr(struct mlx5_ib_mr *mr) wait_event(mr->q_deferred_work, !atomic_read(&mr->num_deferred_work)); + if (is_dmabuf_mr(mr)) + return dma_fence_dmabuf_mr(mr); + dma_fence_odp_mr(mr); } @@ -801,6 +816,52 @@ static int pagefault_implicit_mr(struct mlx5_ib_mr *imr, * Returns: * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are * not accessible, or the MR is no longer valid. + * -EAGAIN: The operation should be retried + * + * >0: Number of pages mapped + */ +static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, struct ib_umem *umem, + u64 io_virt, size_t bcnt, u32 *bytes_mapped, + u32 flags) +{ + struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(umem); + u64 user_va; + u64 end; + int npages; + int err; + + if (unlikely(io_virt < mr->mmkey.iova)) + return -EFAULT; + if (check_add_overflow(io_virt - mr->mmkey.iova, + (u64)umem->address, &user_va)) + return -EFAULT; + + /* Overflow has alreddy been checked at the umem creation time */ + end = umem->address + umem->length; + if (unlikely(user_va >= end || end - user_va < bcnt)) + return -EFAULT; + + dma_resv_lock(umem_dmabuf->attach->dmabuf->resv, NULL); + err = ib_umem_dmabuf_map_pages(umem_dmabuf); + if (!err) + err = mlx5_ib_update_xlt(mr, 0, mr->npages, PAGE_SHIFT, 0); + dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv); + + if (err) + return err; + + if (bytes_mapped) + *bytes_mapped += bcnt; + + npages = (ALIGN(user_va + bcnt, PAGE_SIZE) - + ALIGN_DOWN(user_va, PAGE_SIZE)) >> PAGE_SHIFT; + return npages; +} + +/* + * Returns: + * -EFAULT: The io_virt->bcnt is not within the MR, it covers pages that are + * not accessible, or the MR is no longer valid. * -EAGAIN/-ENOMEM: The operation should be retried * * -EINVAL/others: General internal malfunction @@ -811,6 +872,10 @@ static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt, { struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem); + if (is_dmabuf_mr(mr)) + return pagefault_dmabuf_mr(mr, mr->umem, io_virt, bcnt, + bytes_mapped, flags); + lockdep_assert_held(&mr->dev->odp_srcu); if (unlikely(io_virt < mr->mmkey.iova)) return -EFAULT; @@ -1747,7 +1812,6 @@ static void destroy_prefetch_work(struct prefetch_mr_work *work) { struct mlx5_ib_dev *dev = to_mdev(pd->device); struct mlx5_core_mkey *mmkey; - struct ib_umem_odp *odp; struct mlx5_ib_mr *mr; lockdep_assert_held(&dev->odp_srcu); @@ -1761,11 +1825,9 @@ static void destroy_prefetch_work(struct prefetch_mr_work *work) if (mr->ibmr.pd != pd) return NULL; - odp = to_ib_umem_odp(mr->umem); - /* prefetch with write-access must be supported by the MR */ if (advice == IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE && - !odp->umem.writable) + !mr->umem->writable) return NULL; return mr;