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RDMA/umem: Allow pinned dmabuf umem usage

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Introduce ib_umem_dmabuf_get_pinned() which allows the driver to get a
dmabuf umem which is pinned and does not require move_notify callback
implementation.

The returned umem is pinned and DMA mapped like standard cpu umems, and is
released through ib_umem_release() (incl. unpinning and unmapping).

Link: https://lore.kernel.org/r/20211012120903.96933-3-galpress@amazon.com
Signed-off-by: Gal Pressman <galpress@amazon.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Gal Pressman 2021-10-12 15:09:02 +03:00 committed by Jason Gunthorpe
parent 5460601de5
commit 1e4df4a21c
2 changed files with 62 additions and 0 deletions
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51
drivers/infiniband/core/umem_dmabuf.c
View file

@ -163,12 +163,63 @@ struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
}
EXPORT_SYMBOL(ib_umem_dmabuf_get);
static void
ib_umem_dmabuf_unsupported_move_notify(struct dma_buf_attachment *attach)
{
struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv;
ibdev_warn_ratelimited(umem_dmabuf->umem.ibdev,
"Invalidate callback should not be called when memory is pinned\n");
}
static struct dma_buf_attach_ops ib_umem_dmabuf_attach_pinned_ops = {
.allow_peer2peer = true,
.move_notify = ib_umem_dmabuf_unsupported_move_notify,
};
struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
unsigned long offset,
size_t size, int fd,
int access)
{
struct ib_umem_dmabuf *umem_dmabuf;
int err;
umem_dmabuf = ib_umem_dmabuf_get(device, offset, size, fd, access,
&ib_umem_dmabuf_attach_pinned_ops);
if (IS_ERR(umem_dmabuf))
return umem_dmabuf;
dma_resv_lock(umem_dmabuf->attach->dmabuf->resv, NULL);
err = dma_buf_pin(umem_dmabuf->attach);
if (err)
goto err_release;
umem_dmabuf->pinned = 1;
err = ib_umem_dmabuf_map_pages(umem_dmabuf);
if (err)
goto err_unpin;
dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
return umem_dmabuf;
err_unpin:
dma_buf_unpin(umem_dmabuf->attach);
err_release:
dma_resv_unlock(umem_dmabuf->attach->dmabuf->resv);
ib_umem_release(&umem_dmabuf->umem);
return ERR_PTR(err);
}
EXPORT_SYMBOL(ib_umem_dmabuf_get_pinned);
void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf)
{
struct dma_buf *dmabuf = umem_dmabuf->attach->dmabuf;
dma_resv_lock(dmabuf->resv, NULL);
ib_umem_dmabuf_unmap_pages(umem_dmabuf);
if (umem_dmabuf->pinned)
dma_buf_unpin(umem_dmabuf->attach);
dma_resv_unlock(dmabuf->resv);
dma_buf_detach(dmabuf, umem_dmabuf->attach);

11
include/rdma/ib_umem.h
View file

@ -38,6 +38,7 @@ struct ib_umem_dmabuf {
unsigned long first_sg_offset;
unsigned long last_sg_trim;
void *private;
u8 pinned : 1;
};
static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
@ -139,6 +140,10 @@ struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
unsigned long offset, size_t size,
int fd, int access,
const struct dma_buf_attach_ops *ops);
struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
unsigned long offset,
size_t size, int fd,
int access);
int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
@ -179,6 +184,12 @@ struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline struct ib_umem_dmabuf *
ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
size_t size, int fd, int access)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
{
return -EOPNOTSUPP;