| /* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR MIT) */ |
| /****************************************************************************** |
| * gntdev.h |
| * |
| * Interface to /dev/xen/gntdev. |
| * |
| * Copyright (c) 2007, D G Murray |
| * Copyright (c) 2018, Oleksandr Andrushchenko, EPAM Systems Inc. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License version 2 |
| * as published by the Free Software Foundation; or, when distributed |
| * separately from the Linux kernel or incorporated into other |
| * software packages, subject to the following license: |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this source file (the "Software"), to deal in the Software without |
| * restriction, including without limitation the rights to use, copy, modify, |
| * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| * and to permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * 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 __LINUX_PUBLIC_GNTDEV_H__ |
| #define __LINUX_PUBLIC_GNTDEV_H__ |
| |
| #include <linux/types.h> |
| |
| struct ioctl_gntdev_grant_ref { |
| /* The domain ID of the grant to be mapped. */ |
| __u32 domid; |
| /* The grant reference of the grant to be mapped. */ |
| __u32 ref; |
| }; |
| |
| /* |
| * Inserts the grant references into the mapping table of an instance |
| * of gntdev. N.B. This does not perform the mapping, which is deferred |
| * until mmap() is called with @index as the offset. |
| */ |
| #define IOCTL_GNTDEV_MAP_GRANT_REF \ |
| _IOC(_IOC_NONE, 'G', 0, sizeof(struct ioctl_gntdev_map_grant_ref)) |
| struct ioctl_gntdev_map_grant_ref { |
| /* IN parameters */ |
| /* The number of grants to be mapped. */ |
| __u32 count; |
| __u32 pad; |
| /* OUT parameters */ |
| /* The offset to be used on a subsequent call to mmap(). */ |
| __u64 index; |
| /* Variable IN parameter. */ |
| /* Array of grant references, of size @count. */ |
| struct ioctl_gntdev_grant_ref refs[1]; |
| }; |
| |
| /* |
| * Removes the grant references from the mapping table of an instance of |
| * of gntdev. N.B. munmap() must be called on the relevant virtual address(es) |
| * before this ioctl is called, or an error will result. |
| */ |
| #define IOCTL_GNTDEV_UNMAP_GRANT_REF \ |
| _IOC(_IOC_NONE, 'G', 1, sizeof(struct ioctl_gntdev_unmap_grant_ref)) |
| struct ioctl_gntdev_unmap_grant_ref { |
| /* IN parameters */ |
| /* The offset was returned by the corresponding map operation. */ |
| __u64 index; |
| /* The number of pages to be unmapped. */ |
| __u32 count; |
| __u32 pad; |
| }; |
| |
| /* |
| * Returns the offset in the driver's address space that corresponds |
| * to @vaddr. This can be used to perform a munmap(), followed by an |
| * UNMAP_GRANT_REF ioctl, where no state about the offset is retained by |
| * the caller. The number of pages that were allocated at the same time as |
| * @vaddr is returned in @count. |
| * |
| * N.B. Where more than one page has been mapped into a contiguous range, the |
| * supplied @vaddr must correspond to the start of the range; otherwise |
| * an error will result. It is only possible to munmap() the entire |
| * contiguously-allocated range at once, and not any subrange thereof. |
| */ |
| #define IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR \ |
| _IOC(_IOC_NONE, 'G', 2, sizeof(struct ioctl_gntdev_get_offset_for_vaddr)) |
| struct ioctl_gntdev_get_offset_for_vaddr { |
| /* IN parameters */ |
| /* The virtual address of the first mapped page in a range. */ |
| __u64 vaddr; |
| /* OUT parameters */ |
| /* The offset that was used in the initial mmap() operation. */ |
| __u64 offset; |
| /* The number of pages mapped in the VM area that begins at @vaddr. */ |
| __u32 count; |
| __u32 pad; |
| }; |
| |
| /* |
| * Sets the maximum number of grants that may mapped at once by this gntdev |
| * instance. |
| * |
| * N.B. This must be called before any other ioctl is performed on the device. |
| */ |
| #define IOCTL_GNTDEV_SET_MAX_GRANTS \ |
| _IOC(_IOC_NONE, 'G', 3, sizeof(struct ioctl_gntdev_set_max_grants)) |
| struct ioctl_gntdev_set_max_grants { |
| /* IN parameter */ |
| /* The maximum number of grants that may be mapped at once. */ |
| __u32 count; |
| }; |
| |
| /* |
| * Sets up an unmap notification within the page, so that the other side can do |
| * cleanup if this side crashes. Required to implement cross-domain robust |
| * mutexes or close notification on communication channels. |
| * |
| * Each mapped page only supports one notification; multiple calls referring to |
| * the same page overwrite the previous notification. You must clear the |
| * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it |
| * to occur. |
| */ |
| #define IOCTL_GNTDEV_SET_UNMAP_NOTIFY \ |
| _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntdev_unmap_notify)) |
| struct ioctl_gntdev_unmap_notify { |
| /* IN parameters */ |
| /* Offset in the file descriptor for a byte within the page (same as |
| * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to |
| * be cleared. Otherwise, it can be any byte in the page whose |
| * notification we are adjusting. |
| */ |
| __u64 index; |
| /* Action(s) to take on unmap */ |
| __u32 action; |
| /* Event channel to notify */ |
| __u32 event_channel_port; |
| }; |
| |
| struct gntdev_grant_copy_segment { |
| union { |
| void __user *virt; |
| struct { |
| grant_ref_t ref; |
| __u16 offset; |
| domid_t domid; |
| } foreign; |
| } source, dest; |
| __u16 len; |
| |
| __u16 flags; /* GNTCOPY_* */ |
| __s16 status; /* GNTST_* */ |
| }; |
| |
| /* |
| * Copy between grant references and local buffers. |
| * |
| * The copy is split into @count @segments, each of which can copy |
| * to/from one grant reference. |
| * |
| * Each segment is similar to struct gnttab_copy in the hypervisor ABI |
| * except the local buffer is specified using a virtual address |
| * (instead of a GFN and offset). |
| * |
| * The local buffer may cross a Xen page boundary -- the driver will |
| * split segments into multiple ops if required. |
| * |
| * Returns 0 if all segments have been processed and @status in each |
| * segment is valid. Note that one or more segments may have failed |
| * (status != GNTST_okay). |
| * |
| * If the driver had to split a segment into two or more ops, @status |
| * includes the status of the first failed op for that segment (or |
| * GNTST_okay if all ops were successful). |
| * |
| * If -1 is returned, the status of all segments is undefined. |
| * |
| * EINVAL: A segment has local buffers for both source and |
| * destination. |
| * EINVAL: A segment crosses the boundary of a foreign page. |
| * EFAULT: A segment's local buffer is not accessible. |
| */ |
| #define IOCTL_GNTDEV_GRANT_COPY \ |
| _IOC(_IOC_NONE, 'G', 8, sizeof(struct ioctl_gntdev_grant_copy)) |
| struct ioctl_gntdev_grant_copy { |
| unsigned int count; |
| struct gntdev_grant_copy_segment __user *segments; |
| }; |
| |
| /* Clear (set to zero) the byte specified by index */ |
| #define UNMAP_NOTIFY_CLEAR_BYTE 0x1 |
| /* Send an interrupt on the indicated event channel */ |
| #define UNMAP_NOTIFY_SEND_EVENT 0x2 |
| |
| /* |
| * Flags to be used while requesting memory mapping's backing storage |
| * to be allocated with DMA API. |
| */ |
| |
| /* |
| * The buffer is backed with memory allocated with dma_alloc_wc. |
| */ |
| #define GNTDEV_DMA_FLAG_WC (1 << 0) |
| |
| /* |
| * The buffer is backed with memory allocated with dma_alloc_coherent. |
| */ |
| #define GNTDEV_DMA_FLAG_COHERENT (1 << 1) |
| |
| /* |
| * Create a dma-buf [1] from grant references @refs of count @count provided |
| * by the foreign domain @domid with flags @flags. |
| * |
| * By default dma-buf is backed by system memory pages, but by providing |
| * one of the GNTDEV_DMA_FLAG_XXX flags it can also be created as |
| * a DMA write-combine or coherent buffer, e.g. allocated with dma_alloc_wc/ |
| * dma_alloc_coherent. |
| * |
| * Returns 0 if dma-buf was successfully created and the corresponding |
| * dma-buf's file descriptor is returned in @fd. |
| * |
| * [1] Documentation/driver-api/dma-buf.rst |
| */ |
| |
| #define IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS \ |
| _IOC(_IOC_NONE, 'G', 9, \ |
| sizeof(struct ioctl_gntdev_dmabuf_exp_from_refs)) |
| struct ioctl_gntdev_dmabuf_exp_from_refs { |
| /* IN parameters. */ |
| /* Specific options for this dma-buf: see GNTDEV_DMA_FLAG_XXX. */ |
| __u32 flags; |
| /* Number of grant references in @refs array. */ |
| __u32 count; |
| /* OUT parameters. */ |
| /* File descriptor of the dma-buf. */ |
| __u32 fd; |
| /* The domain ID of the grant references to be mapped. */ |
| __u32 domid; |
| /* Variable IN parameter. */ |
| /* Array of grant references of size @count. */ |
| __u32 refs[1]; |
| }; |
| |
| /* |
| * This will block until the dma-buf with the file descriptor @fd is |
| * released. This is only valid for buffers created with |
| * IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS. |
| * |
| * If within @wait_to_ms milliseconds the buffer is not released |
| * then -ETIMEDOUT error is returned. |
| * If the buffer with the file descriptor @fd does not exist or has already |
| * been released, then -ENOENT is returned. For valid file descriptors |
| * this must not be treated as error. |
| */ |
| #define IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED \ |
| _IOC(_IOC_NONE, 'G', 10, \ |
| sizeof(struct ioctl_gntdev_dmabuf_exp_wait_released)) |
| struct ioctl_gntdev_dmabuf_exp_wait_released { |
| /* IN parameters */ |
| __u32 fd; |
| __u32 wait_to_ms; |
| }; |
| |
| /* |
| * Import a dma-buf with file descriptor @fd and export granted references |
| * to the pages of that dma-buf into array @refs of size @count. |
| */ |
| #define IOCTL_GNTDEV_DMABUF_IMP_TO_REFS \ |
| _IOC(_IOC_NONE, 'G', 11, \ |
| sizeof(struct ioctl_gntdev_dmabuf_imp_to_refs)) |
| struct ioctl_gntdev_dmabuf_imp_to_refs { |
| /* IN parameters. */ |
| /* File descriptor of the dma-buf. */ |
| __u32 fd; |
| /* Number of grant references in @refs array. */ |
| __u32 count; |
| /* The domain ID for which references to be granted. */ |
| __u32 domid; |
| /* Reserved - must be zero. */ |
| __u32 reserved; |
| /* OUT parameters. */ |
| /* Array of grant references of size @count. */ |
| __u32 refs[1]; |
| }; |
| |
| /* |
| * This will close all references to the imported buffer with file descriptor |
| * @fd, so it can be released by the owner. This is only valid for buffers |
| * created with IOCTL_GNTDEV_DMABUF_IMP_TO_REFS. |
| */ |
| #define IOCTL_GNTDEV_DMABUF_IMP_RELEASE \ |
| _IOC(_IOC_NONE, 'G', 12, \ |
| sizeof(struct ioctl_gntdev_dmabuf_imp_release)) |
| struct ioctl_gntdev_dmabuf_imp_release { |
| /* IN parameters */ |
| __u32 fd; |
| __u32 reserved; |
| }; |
| |
| #endif /* __LINUX_PUBLIC_GNTDEV_H__ */ |