^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * dma-bufs for virtio exported objects
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2020 Google, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/virtio_dma_buf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * virtio_dma_buf_export - Creates a new dma-buf for a virtio exported object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * @exp_info: [in] see dma_buf_export(). ops MUST refer to a dma_buf_ops
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * struct embedded in a virtio_dma_buf_ops.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * This wraps dma_buf_export() to allow virtio drivers to create a dma-buf
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * for an virtio exported object that can be queried by other virtio drivers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * for the object's UUID.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct dma_buf *virtio_dma_buf_export
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) (const struct dma_buf_export_info *exp_info)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) const struct virtio_dma_buf_ops *virtio_ops =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) container_of(exp_info->ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) const struct virtio_dma_buf_ops, ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) if (!exp_info->ops ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) !virtio_ops->get_uuid) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) if (!(IS_ENABLED(CONFIG_CFI_CLANG) && IS_ENABLED(CONFIG_MODULES)) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) exp_info->ops->attach != &virtio_dma_buf_attach)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) return ERR_PTR(-EINVAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) return dma_buf_export(exp_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) EXPORT_SYMBOL(virtio_dma_buf_export);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * virtio_dma_buf_attach - mandatory attach callback for virtio dma-bufs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) int virtio_dma_buf_attach(struct dma_buf *dma_buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) struct dma_buf_attachment *attach)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) const struct virtio_dma_buf_ops *ops =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) container_of(dma_buf->ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) const struct virtio_dma_buf_ops, ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) if (ops->device_attach) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) ret = ops->device_attach(dma_buf, attach);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) EXPORT_SYMBOL(virtio_dma_buf_attach);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * is_virtio_dma_buf - returns true if the given dma-buf is a virtio dma-buf
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) * @dma_buf: buffer to query
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) bool is_virtio_dma_buf(struct dma_buf *dma_buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) if (IS_ENABLED(CONFIG_CFI_CLANG) && IS_ENABLED(CONFIG_MODULES))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) return dma_buf->ops->attach == &virtio_dma_buf_attach;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) EXPORT_SYMBOL(is_virtio_dma_buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) * virtio_dma_buf_get_uuid - gets a virtio dma-buf's exported object's uuid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) * @dma_buf: [in] buffer to query
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) * @uuid: [out] the uuid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) * Returns: 0 on success, negative on failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) int virtio_dma_buf_get_uuid(struct dma_buf *dma_buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) uuid_t *uuid)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) const struct virtio_dma_buf_ops *ops =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) container_of(dma_buf->ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) const struct virtio_dma_buf_ops, ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) if (!is_virtio_dma_buf(dma_buf))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) return ops->get_uuid(dma_buf, uuid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) EXPORT_SYMBOL(virtio_dma_buf_get_uuid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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