diff options
Diffstat (limited to 'drivers/misc/mic/scif/scif_rma.h')
| -rw-r--r-- | drivers/misc/mic/scif/scif_rma.h | 464 |
1 files changed, 464 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_rma.h b/drivers/misc/mic/scif/scif_rma.h new file mode 100644 index 000000000..fa6722279 --- /dev/null +++ b/drivers/misc/mic/scif/scif_rma.h @@ -0,0 +1,464 @@ +/* + * Intel MIC Platform Software Stack (MPSS) + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2015 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * BSD LICENSE + * + * Copyright(c) 2015 Intel Corporation. + * + * 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. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Intel SCIF driver. + * + */ +#ifndef SCIF_RMA_H +#define SCIF_RMA_H + +#include <linux/dma_remapping.h> +#include <linux/mmu_notifier.h> + +#include "../bus/scif_bus.h" + +/* If this bit is set then the mark is a remote fence mark */ +#define SCIF_REMOTE_FENCE_BIT 31 +/* Magic value used to indicate a remote fence request */ +#define SCIF_REMOTE_FENCE BIT_ULL(SCIF_REMOTE_FENCE_BIT) + +#define SCIF_MAX_UNALIGNED_BUF_SIZE (1024 * 1024ULL) +#define SCIF_KMEM_UNALIGNED_BUF_SIZE (SCIF_MAX_UNALIGNED_BUF_SIZE + \ + (L1_CACHE_BYTES << 1)) + +#define SCIF_IOVA_START_PFN (1) +#define SCIF_IOVA_PFN(addr) ((addr) >> PAGE_SHIFT) +#define SCIF_DMA_64BIT_PFN SCIF_IOVA_PFN(DMA_BIT_MASK(64)) +#define SCIF_DMA_63BIT_PFN SCIF_IOVA_PFN(DMA_BIT_MASK(63)) + +/* + * struct scif_endpt_rma_info - Per Endpoint Remote Memory Access Information + * + * @reg_list: List of registration windows for self + * @remote_reg_list: List of registration windows for peer + * @iovad: Offset generator + * @rma_lock: Synchronizes access to self/remote list and also protects the + * window from being destroyed while RMAs are in progress. + * @tc_lock: Synchronizes access to temporary cached windows list + * for SCIF Registration Caching. + * @mmn_lock: Synchronizes access to the list of MMU notifiers registered + * @tw_refcount: Keeps track of number of outstanding temporary registered + * windows created by scif_vreadfrom/scif_vwriteto which have + * not been destroyed. + * @tcw_refcount: Same as tw_refcount but for temporary cached windows + * @tcw_total_pages: Same as tcw_refcount but in terms of pages pinned + * @mmn_list: MMU notifier so that we can destroy the windows when required + * @fence_refcount: Keeps track of number of outstanding remote fence + * requests which have been received by the peer. + * @dma_chan: DMA channel used for all DMA transfers for this endpoint. + * @async_list_del: Detect asynchronous list entry deletion + * @vma_list: List of vmas with remote memory mappings + * @markwq: Wait queue used for scif_fence_mark/scif_fence_wait +*/ +struct scif_endpt_rma_info { + struct list_head reg_list; + struct list_head remote_reg_list; + struct iova_domain iovad; + struct mutex rma_lock; + spinlock_t tc_lock; + struct mutex mmn_lock; + atomic_t tw_refcount; + atomic_t tcw_refcount; + atomic_t tcw_total_pages; + struct list_head mmn_list; + atomic_t fence_refcount; + struct dma_chan *dma_chan; + int async_list_del; + struct list_head vma_list; + wait_queue_head_t markwq; +}; + +/* + * struct scif_fence_info - used for tracking fence requests + * + * @state: State of this transfer + * @wq: Fences wait on this queue + * @dma_mark: Used for storing the DMA mark + */ +struct scif_fence_info { + enum scif_msg_state state; + struct completion comp; + int dma_mark; +}; + +/* + * struct scif_remote_fence_info - used for tracking remote fence requests + * + * @msg: List of SCIF node QP fence messages + * @list: Link to list of remote fence requests + */ +struct scif_remote_fence_info { + struct scifmsg msg; + struct list_head list; +}; + +/* + * Specifies whether an RMA operation can span across partial windows, a single + * window or multiple contiguous windows. Mmaps can span across partial windows. + * Unregistration can span across complete windows. scif_get_pages() can span a + * single window. A window can also be of type self or peer. + */ +enum scif_window_type { + SCIF_WINDOW_PARTIAL, + SCIF_WINDOW_SINGLE, + SCIF_WINDOW_FULL, + SCIF_WINDOW_SELF, + SCIF_WINDOW_PEER +}; + +/* The number of physical addresses that can be stored in a PAGE. */ +#define SCIF_NR_ADDR_IN_PAGE (0x1000 >> 3) + +/* + * struct scif_rma_lookup - RMA lookup data structure for page list transfers + * + * Store an array of lookup offsets. Each offset in this array maps + * one 4K page containing 512 physical addresses i.e. 2MB. 512 such + * offsets in a 4K page will correspond to 1GB of registered address space. + + * @lookup: Array of offsets + * @offset: DMA offset of lookup array + */ +struct scif_rma_lookup { + dma_addr_t *lookup; + dma_addr_t offset; +}; + +/* + * struct scif_pinned_pages - A set of pinned pages obtained with + * scif_pin_pages() which could be part of multiple registered + * windows across different end points. + * + * @nr_pages: Number of pages which is defined as a s64 instead of an int + * to avoid sign extension with buffers >= 2GB + * @prot: read/write protections + * @map_flags: Flags specified during the pin operation + * @ref_count: Reference count bumped in terms of number of pages + * @magic: A magic value + * @pages: Array of pointers to struct pages populated with get_user_pages(..) + */ +struct scif_pinned_pages { + s64 nr_pages; + int prot; + int map_flags; + atomic_t ref_count; + u64 magic; + struct page **pages; +}; + +/* + * struct scif_status - Stores DMA status update information + * + * @src_dma_addr: Source buffer DMA address + * @val: src location for value to be written to the destination + * @ep: SCIF endpoint + */ +struct scif_status { + dma_addr_t src_dma_addr; + u64 val; + struct scif_endpt *ep; +}; + +/* + * struct scif_window - Registration Window for Self and Remote + * + * @nr_pages: Number of pages which is defined as a s64 instead of an int + * to avoid sign extension with buffers >= 2GB + * @nr_contig_chunks: Number of contiguous physical chunks + * @prot: read/write protections + * @ref_count: reference count in terms of number of pages + * @magic: Cookie to detect corruption + * @offset: registered offset + * @va_for_temp: va address that this window represents + * @dma_mark: Used to determine if all DMAs against the window are done + * @ep: Pointer to EP. Useful for passing EP around with messages to + avoid expensive list traversals. + * @list: link to list of windows for the endpoint + * @type: self or peer window + * @peer_window: Pointer to peer window. Useful for sending messages to peer + * without requiring an extra list traversal + * @unreg_state: unregistration state + * @offset_freed: True if the offset has been freed + * @temp: True for temporary windows created via scif_vreadfrom/scif_vwriteto + * @mm: memory descriptor for the task_struct which initiated the RMA + * @st: scatter gather table for DMA mappings with IOMMU enabled + * @pinned_pages: The set of pinned_pages backing this window + * @alloc_handle: Handle for sending ALLOC_REQ + * @regwq: Wait Queue for an registration (N)ACK + * @reg_state: Registration state + * @unregwq: Wait Queue for an unregistration (N)ACK + * @dma_addr_lookup: Lookup for physical addresses used for DMA + * @nr_lookup: Number of entries in lookup + * @mapped_offset: Offset used to map the window by the peer + * @dma_addr: Array of physical addresses used for Mgmt node & MIC initiated DMA + * @num_pages: Array specifying number of pages for each physical address + */ +struct scif_window { + s64 nr_pages; + int nr_contig_chunks; + int prot; + int ref_count; + u64 magic; + s64 offset; + unsigned long va_for_temp; + int dma_mark; + u64 ep; + struct list_head list; + enum scif_window_type type; + u64 peer_window; + enum scif_msg_state unreg_state; + bool offset_freed; + bool temp; + struct mm_struct *mm; + struct sg_table *st; + union { + struct { + struct scif_pinned_pages *pinned_pages; + struct scif_allocmsg alloc_handle; + wait_queue_head_t regwq; + enum scif_msg_state reg_state; + wait_queue_head_t unregwq; + }; + struct { + struct scif_rma_lookup dma_addr_lookup; + struct scif_rma_lookup num_pages_lookup; + int nr_lookup; + dma_addr_t mapped_offset; + }; + }; + dma_addr_t *dma_addr; + u64 *num_pages; +} __packed; + +/* + * scif_mmu_notif - SCIF mmu notifier information + * + * @mmu_notifier ep_mmu_notifier: MMU notifier operations + * @tc_reg_list: List of temp registration windows for self + * @mm: memory descriptor for the task_struct which initiated the RMA + * @ep: SCIF endpoint + * @list: link to list of MMU notifier information + */ +struct scif_mmu_notif { +#ifdef CONFIG_MMU_NOTIFIER + struct mmu_notifier ep_mmu_notifier; +#endif + struct list_head tc_reg_list; + struct mm_struct *mm; + struct scif_endpt *ep; + struct list_head list; +}; + +enum scif_rma_dir { + SCIF_LOCAL_TO_REMOTE, + SCIF_REMOTE_TO_LOCAL +}; + +extern struct kmem_cache *unaligned_cache; +/* Initialize RMA for this EP */ +void scif_rma_ep_init(struct scif_endpt *ep); +/* Check if epd can be uninitialized */ +int scif_rma_ep_can_uninit(struct scif_endpt *ep); +/* Obtain a new offset. Callee must grab RMA lock */ +int scif_get_window_offset(struct scif_endpt *ep, int flags, + s64 offset, int nr_pages, s64 *out_offset); +/* Free offset. Callee must grab RMA lock */ +void scif_free_window_offset(struct scif_endpt *ep, + struct scif_window *window, s64 offset); +/* Create self registration window */ +struct scif_window *scif_create_window(struct scif_endpt *ep, int nr_pages, + s64 offset, bool temp); +/* Destroy self registration window.*/ +int scif_destroy_window(struct scif_endpt *ep, struct scif_window *window); +void scif_unmap_window(struct scif_dev *remote_dev, struct scif_window *window); +/* Map pages of self window to Aperture/PCI */ +int scif_map_window(struct scif_dev *remote_dev, + struct scif_window *window); +/* Unregister a self window */ +int scif_unregister_window(struct scif_window *window); +/* Destroy remote registration window */ +void +scif_destroy_remote_window(struct scif_window *window); +/* remove valid remote memory mappings from process address space */ +void scif_zap_mmaps(int node); +/* Query if any applications have remote memory mappings */ +bool scif_rma_do_apps_have_mmaps(int node); +/* Cleanup remote registration lists for zombie endpoints */ +void scif_cleanup_rma_for_zombies(int node); +/* Reserve a DMA channel for a particular endpoint */ +int scif_reserve_dma_chan(struct scif_endpt *ep); +/* Setup a DMA mark for an endpoint */ +int _scif_fence_mark(scif_epd_t epd, int *mark); +int scif_prog_signal(scif_epd_t epd, off_t offset, u64 val, + enum scif_window_type type); +void scif_alloc_req(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_alloc_gnt_rej(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_free_virt(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_reg(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_unreg(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_reg_ack(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_reg_nack(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_unreg_ack(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_unreg_nack(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_munmap(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_mark(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_mark_resp(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_wait(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_wait_resp(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_sig_local(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_sig_remote(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_recv_sig_resp(struct scif_dev *scifdev, struct scifmsg *msg); +void scif_mmu_notif_handler(struct work_struct *work); +void scif_rma_handle_remote_fences(void); +void scif_rma_destroy_windows(void); +void scif_rma_destroy_tcw_invalid(void); +int scif_drain_dma_intr(struct scif_hw_dev *sdev, struct dma_chan *chan); + +struct scif_window_iter { + s64 offset; + int index; +}; + +static inline void +scif_init_window_iter(struct scif_window *window, struct scif_window_iter *iter) +{ + iter->offset = window->offset; + iter->index = 0; +} + +dma_addr_t scif_off_to_dma_addr(struct scif_window *window, s64 off, + size_t *nr_bytes, + struct scif_window_iter *iter); +static inline +dma_addr_t __scif_off_to_dma_addr(struct scif_window *window, s64 off) +{ + return scif_off_to_dma_addr(window, off, NULL, NULL); +} + +static inline bool scif_unaligned(off_t src_offset, off_t dst_offset) +{ + src_offset = src_offset & (L1_CACHE_BYTES - 1); + dst_offset = dst_offset & (L1_CACHE_BYTES - 1); + return !(src_offset == dst_offset); +} + +/* + * scif_zalloc: + * @size: Size of the allocation request. + * + * Helper API which attempts to allocate zeroed pages via + * __get_free_pages(..) first and then falls back on + * vzalloc(..) if that fails. + */ +static inline void *scif_zalloc(size_t size) +{ + void *ret = NULL; + size_t align = ALIGN(size, PAGE_SIZE); + + if (align && get_order(align) < MAX_ORDER) + ret = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(align)); + return ret ? ret : vzalloc(align); +} + +/* + * scif_free: + * @addr: Address to be freed. + * @size: Size of the allocation. + * Helper API which frees memory allocated via scif_zalloc(). + */ +static inline void scif_free(void *addr, size_t size) +{ + size_t align = ALIGN(size, PAGE_SIZE); + + if (is_vmalloc_addr(addr)) + vfree(addr); + else + free_pages((unsigned long)addr, get_order(align)); +} + +static inline void scif_get_window(struct scif_window *window, int nr_pages) +{ + window->ref_count += nr_pages; +} + +static inline void scif_put_window(struct scif_window *window, int nr_pages) +{ + window->ref_count -= nr_pages; +} + +static inline void scif_set_window_ref(struct scif_window *window, int nr_pages) +{ + window->ref_count = nr_pages; +} + +static inline void +scif_queue_for_cleanup(struct scif_window *window, struct list_head *list) +{ + spin_lock(&scif_info.rmalock); + list_add_tail(&window->list, list); + spin_unlock(&scif_info.rmalock); + schedule_work(&scif_info.misc_work); +} + +static inline void __scif_rma_destroy_tcw_helper(struct scif_window *window) +{ + list_del_init(&window->list); + scif_queue_for_cleanup(window, &scif_info.rma_tc); +} + +static inline bool scif_is_iommu_enabled(void) +{ +#ifdef CONFIG_INTEL_IOMMU + return intel_iommu_enabled; +#else + return false; +#endif +} +#endif /* SCIF_RMA_H */ |