diff options
author | Shachar Raindel <raindel@mellanox.com> | 2014-12-11 16:04:17 +0100 |
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committer | Roland Dreier <roland@purestorage.com> | 2014-12-16 03:13:36 +0100 |
commit | 8ada2c1c0c1d75a60723cd2ca7d49c594a146af6 (patch) | |
tree | a80d10bb8cf4888a7f6313698a40980de5724b51 /include/rdma/ib_umem_odp.h | |
parent | IB/core: Add flags for on demand paging support (diff) | |
download | linux-8ada2c1c0c1d75a60723cd2ca7d49c594a146af6.tar.xz linux-8ada2c1c0c1d75a60723cd2ca7d49c594a146af6.zip |
IB/core: Add support for on demand paging regions
* Extend the umem struct to keep the ODP related data.
* Allocate and initialize the ODP related information in the umem
(page_list, dma_list) and freeing as needed in the end of the run.
* Store a reference to the process PID struct in the ucontext. Used to
safely obtain the task_struct and the mm during fault handling,
without preventing the task destruction if needed.
* Add 2 helper functions: ib_umem_odp_map_dma_pages and
ib_umem_odp_unmap_dma_pages. These functions get the DMA addresses
of specific pages of the umem (and, currently, pin them).
* Support for page faults only - IB core will keep the reference on
the pages used and call put_page when freeing an ODP umem
area. Invalidations support will be added in a later patch.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Diffstat (limited to 'include/rdma/ib_umem_odp.h')
-rw-r--r-- | include/rdma/ib_umem_odp.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/include/rdma/ib_umem_odp.h b/include/rdma/ib_umem_odp.h new file mode 100644 index 000000000000..b5a2df1923b7 --- /dev/null +++ b/include/rdma/ib_umem_odp.h @@ -0,0 +1,97 @@ +/* + * Copyright (c) 2014 Mellanox Technologies. 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 + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifndef IB_UMEM_ODP_H +#define IB_UMEM_ODP_H + +#include <rdma/ib_umem.h> + +struct ib_umem_odp { + /* + * An array of the pages included in the on-demand paging umem. + * Indices of pages that are currently not mapped into the device will + * contain NULL. + */ + struct page **page_list; + /* + * An array of the same size as page_list, with DMA addresses mapped + * for pages the pages in page_list. The lower two bits designate + * access permissions. See ODP_READ_ALLOWED_BIT and + * ODP_WRITE_ALLOWED_BIT. + */ + dma_addr_t *dma_list; + /* + * The umem_mutex protects the page_list and dma_list fields of an ODP + * umem, allowing only a single thread to map/unmap pages. + */ + struct mutex umem_mutex; + void *private; /* for the HW driver to use. */ +}; + +#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING + +int ib_umem_odp_get(struct ib_ucontext *context, struct ib_umem *umem); + +void ib_umem_odp_release(struct ib_umem *umem); + +/* + * The lower 2 bits of the DMA address signal the R/W permissions for + * the entry. To upgrade the permissions, provide the appropriate + * bitmask to the map_dma_pages function. + * + * Be aware that upgrading a mapped address might result in change of + * the DMA address for the page. + */ +#define ODP_READ_ALLOWED_BIT (1<<0ULL) +#define ODP_WRITE_ALLOWED_BIT (1<<1ULL) + +#define ODP_DMA_ADDR_MASK (~(ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) + +int ib_umem_odp_map_dma_pages(struct ib_umem *umem, u64 start_offset, u64 bcnt, + u64 access_mask, unsigned long current_seq); + +void ib_umem_odp_unmap_dma_pages(struct ib_umem *umem, u64 start_offset, + u64 bound); + +#else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ + +static inline int ib_umem_odp_get(struct ib_ucontext *context, + struct ib_umem *umem) +{ + return -EINVAL; +} + +static inline void ib_umem_odp_release(struct ib_umem *umem) {} + +#endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ + +#endif /* IB_UMEM_ODP_H */ |