Introduce DMA-backed GEM buffer objects for the QDA accelerator driver and integrate them with the existing memory manager and IOMMU device abstraction.
A new qda_gem_obj structure wraps drm_gem_object and tracks the kernel virtual address, DMA address, size and owning qda_iommu_device. qda_gem_create_object() allocates a GEM object, aligns the requested size, and uses qda_memory_manager_alloc() to obtain DMA-coherent memory from a per-process IOMMU device. The GEM object implements a .mmap callback that validates the VMA offset and calls into qda_dma_mmap(), which maps the DMA memory into userspace and sets appropriate VMA flags. The DMA backend is implemented in qda_memory_dma.c, which allocates and frees coherent memory via dma_alloc_coherent() and dma_free_coherent(), while storing a SID-prefixed DMA address in the GEM object for later use by DSP firmware. The memory manager is extended to maintain a mapping from processes to IOMMU devices using qda_file_priv and a process_assignment_lock, and provides qda_memory_manager_alloc() and qda_memory_manager_free() helpers for GEM allocations. This patch lays the groundwork for GEM allocation and mmap IOCTLs as well as future PRIME and job submission support for QDA buffers. Signed-off-by: Ekansh Gupta <[email protected]> --- drivers/accel/qda/Makefile | 2 + drivers/accel/qda/qda_drv.c | 23 +++- drivers/accel/qda/qda_drv.h | 7 ++ drivers/accel/qda/qda_gem.c | 187 +++++++++++++++++++++++++++++++ drivers/accel/qda/qda_gem.h | 63 +++++++++++ drivers/accel/qda/qda_memory_dma.c | 91 ++++++++++++++++ drivers/accel/qda/qda_memory_dma.h | 46 ++++++++ drivers/accel/qda/qda_memory_manager.c | 194 +++++++++++++++++++++++++++++++++ drivers/accel/qda/qda_memory_manager.h | 33 ++++++ 9 files changed, 645 insertions(+), 1 deletion(-) diff --git a/drivers/accel/qda/Makefile b/drivers/accel/qda/Makefile index f547398e1a72..88c324fa382c 100644 --- a/drivers/accel/qda/Makefile +++ b/drivers/accel/qda/Makefile @@ -11,5 +11,7 @@ qda-y := \ qda_cb.o \ qda_memory_manager.o \ qda_ioctl.o \ + qda_gem.o \ + qda_memory_dma.o \ obj-$(CONFIG_DRM_ACCEL_QDA_COMPUTE_BUS) += qda_compute_bus.o diff --git a/drivers/accel/qda/qda_drv.c b/drivers/accel/qda/qda_drv.c index 86758a9cd982..19798359b14e 100644 --- a/drivers/accel/qda/qda_drv.c +++ b/drivers/accel/qda/qda_drv.c @@ -15,7 +15,7 @@ #include "qda_ioctl.h" #include "qda_rpmsg.h" -static struct qda_drm_priv *get_drm_priv_from_device(struct drm_device *dev) +struct qda_drm_priv *get_drm_priv_from_device(struct drm_device *dev) { if (!dev) return NULL; @@ -88,6 +88,7 @@ static int qda_open(struct drm_device *dev, struct drm_file *file) return -ENOMEM; qda_file_priv->pid = current->pid; + qda_file_priv->assigned_iommu_dev = NULL; /* Will be assigned on first allocation */ qda_user = alloc_qda_user(qdev); if (!qda_user) { @@ -118,6 +119,26 @@ static void qda_postclose(struct drm_device *dev, struct drm_file *file) qda_file_priv = (struct qda_file_priv *)file->driver_priv; if (qda_file_priv) { + if (qda_file_priv->assigned_iommu_dev) { + struct qda_iommu_device *iommu_dev = qda_file_priv->assigned_iommu_dev; + unsigned long flags; + + /* Decrement reference count - if it reaches 0, reset PID assignment */ + if (refcount_dec_and_test(&iommu_dev->refcount)) { + /* Last reference released - reset PID assignment */ + spin_lock_irqsave(&iommu_dev->lock, flags); + iommu_dev->assigned_pid = 0; + iommu_dev->assigned_file_priv = NULL; + spin_unlock_irqrestore(&iommu_dev->lock, flags); + + qda_dbg(qdev, "Reset PID assignment for IOMMU device %u (process %d exited)\n", + iommu_dev->id, qda_file_priv->pid); + } else { + qda_dbg(qdev, "Decremented reference for IOMMU device %u from process %d\n", + iommu_dev->id, qda_file_priv->pid); + } + } + qda_user = qda_file_priv->qda_user; if (qda_user) free_qda_user(qda_user); diff --git a/drivers/accel/qda/qda_drv.h b/drivers/accel/qda/qda_drv.h index e0ba37702a86..8a2cd474958b 100644 --- a/drivers/accel/qda/qda_drv.h +++ b/drivers/accel/qda/qda_drv.h @@ -33,6 +33,8 @@ struct qda_file_priv { pid_t pid; /* Pointer to qda_user structure for backward compatibility */ struct qda_user *qda_user; + /* IOMMU device assigned to this process */ + struct qda_iommu_device *assigned_iommu_dev; }; /** @@ -153,4 +155,9 @@ void qda_deinit_device(struct qda_dev *qdev); int qda_register_device(struct qda_dev *qdev); void qda_unregister_device(struct qda_dev *qdev); +/* + * Utility function to get DRM private data from DRM device + */ +struct qda_drm_priv *get_drm_priv_from_device(struct drm_device *dev); + #endif /* __QDA_DRV_H__ */ diff --git a/drivers/accel/qda/qda_gem.c b/drivers/accel/qda/qda_gem.c new file mode 100644 index 000000000000..bbd54e2502d3 --- /dev/null +++ b/drivers/accel/qda/qda_gem.c @@ -0,0 +1,187 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. +#include <drm/drm_gem.h> +#include <drm/drm_prime.h> +#include <linux/slab.h> +#include <linux/dma-mapping.h> +#include "qda_drv.h" +#include "qda_gem.h" +#include "qda_memory_manager.h" +#include "qda_memory_dma.h" + +static int validate_gem_obj_for_mmap(struct qda_gem_obj *qda_gem_obj) +{ + if (qda_gem_obj->size == 0) { + qda_err(NULL, "Invalid GEM object size\n"); + return -EINVAL; + } + if (!qda_gem_obj->iommu_dev || !qda_gem_obj->iommu_dev->dev) { + qda_err(NULL, "Allocated buffer missing IOMMU device\n"); + return -EINVAL; + } + if (!qda_gem_obj->iommu_dev->dev) { + qda_err(NULL, "Allocated buffer missing IOMMU device\n"); + return -EINVAL; + } + if (!qda_gem_obj->virt) { + qda_err(NULL, "Allocated buffer missing virtual address\n"); + return -EINVAL; + } + if (qda_gem_obj->dma_addr == 0) { + qda_err(NULL, "Allocated buffer missing DMA address\n"); + return -EINVAL; + } + + return 0; +} + +static int validate_vma_offset(struct drm_gem_object *drm_obj, struct vm_area_struct *vma) +{ + u64 expected_offset = drm_vma_node_offset_addr(&drm_obj->vma_node); + u64 actual_offset = vma->vm_pgoff << PAGE_SHIFT; + + if (actual_offset != expected_offset) { + qda_err(NULL, "VMA offset mismatch: expected=0x%llx, actual=0x%llx\n", + expected_offset, actual_offset); + return -EINVAL; + } + + return 0; +} + +static void setup_vma_flags(struct vm_area_struct *vma) +{ + vm_flags_set(vma, VM_DONTEXPAND); + vm_flags_set(vma, VM_DONTDUMP); +} + +void qda_gem_free_object(struct drm_gem_object *gem_obj) +{ + struct qda_gem_obj *qda_gem_obj = to_qda_gem_obj(gem_obj); + struct qda_drm_priv *drm_priv = get_drm_priv_from_device(gem_obj->dev); + + if (qda_gem_obj->virt) { + if (drm_priv && drm_priv->iommu_mgr) + qda_memory_manager_free(drm_priv->iommu_mgr, qda_gem_obj); + } + + drm_gem_object_release(gem_obj); + kfree(qda_gem_obj); +} + +int qda_gem_mmap_obj(struct drm_gem_object *drm_obj, struct vm_area_struct *vma) +{ + struct qda_gem_obj *qda_gem_obj = to_qda_gem_obj(drm_obj); + int ret; + + ret = validate_gem_obj_for_mmap(qda_gem_obj); + if (ret) { + qda_err(NULL, "GEM object validation failed: %d\n", ret); + return ret; + } + + ret = validate_vma_offset(drm_obj, vma); + if (ret) { + qda_err(NULL, "VMA offset validation failed: %d\n", ret); + return ret; + } + + /* Reset vm_pgoff for DMA mmap */ + vma->vm_pgoff = 0; + + ret = qda_dma_mmap(qda_gem_obj, vma); + + if (ret == 0) { + setup_vma_flags(vma); + qda_dbg(NULL, "GEM object mapped successfully\n"); + } else { + qda_err(NULL, "GEM object mmap failed: %d\n", ret); + } + + return ret; +} + +static const struct drm_gem_object_funcs qda_gem_object_funcs = { + .free = qda_gem_free_object, + .mmap = qda_gem_mmap_obj, +}; + +struct qda_gem_obj *qda_gem_alloc_object(struct drm_device *drm_dev, size_t aligned_size) +{ + struct qda_gem_obj *qda_gem_obj; + int ret; + + qda_gem_obj = kzalloc_obj(*qda_gem_obj, GFP_KERNEL); + if (!qda_gem_obj) + return ERR_PTR(-ENOMEM); + + ret = drm_gem_object_init(drm_dev, &qda_gem_obj->base, aligned_size); + if (ret) { + qda_err(NULL, "Failed to initialize GEM object: %d\n", ret); + kfree(qda_gem_obj); + return ERR_PTR(ret); + } + + qda_gem_obj->base.funcs = &qda_gem_object_funcs; + qda_gem_obj->size = aligned_size; + + qda_dbg(NULL, "Allocated GEM object size=%zu\n", aligned_size); + return qda_gem_obj; +} + +void qda_gem_cleanup_object(struct qda_gem_obj *qda_gem_obj) +{ + drm_gem_object_release(&qda_gem_obj->base); + kfree(qda_gem_obj); +} + +struct drm_gem_object *qda_gem_lookup_object(struct drm_file *file_priv, u32 handle) +{ + struct drm_gem_object *gem_obj; + + gem_obj = drm_gem_object_lookup(file_priv, handle); + if (!gem_obj) + return ERR_PTR(-ENOENT); + + return gem_obj; +} + +int qda_gem_create_handle(struct drm_file *file_priv, struct drm_gem_object *gem_obj, u32 *handle) +{ + int ret; + + ret = drm_gem_handle_create(file_priv, gem_obj, handle); + drm_gem_object_put(gem_obj); + + return ret; +} + +struct drm_gem_object *qda_gem_create_object(struct drm_device *drm_dev, + struct qda_memory_manager *iommu_mgr, size_t size, + struct drm_file *file_priv) +{ + struct qda_gem_obj *qda_gem_obj; + size_t aligned_size; + int ret; + + if (size == 0) { + qda_err(NULL, "Invalid size for GEM object creation\n"); + return ERR_PTR(-EINVAL); + } + + aligned_size = PAGE_ALIGN(size); + + qda_gem_obj = qda_gem_alloc_object(drm_dev, aligned_size); + if (IS_ERR(qda_gem_obj)) + return (struct drm_gem_object *)qda_gem_obj; + + ret = qda_memory_manager_alloc(iommu_mgr, qda_gem_obj, file_priv); + if (ret) { + qda_err(NULL, "Memory manager allocation failed: %d\n", ret); + qda_gem_cleanup_object(qda_gem_obj); + return ERR_PTR(ret); + } + + qda_dbg(NULL, "GEM object created successfully size=%zu\n", aligned_size); + return &qda_gem_obj->base; +} diff --git a/drivers/accel/qda/qda_gem.h b/drivers/accel/qda/qda_gem.h new file mode 100644 index 000000000000..caae9cda5363 --- /dev/null +++ b/drivers/accel/qda/qda_gem.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + */ +#ifndef _QDA_GEM_H +#define _QDA_GEM_H + +#include <linux/xarray.h> +#include <drm/drm_device.h> +#include <drm/drm_gem.h> +#include <linux/dma-mapping.h> + +/* Forward declarations */ +struct qda_memory_manager; +struct qda_iommu_device; + +/** + * struct qda_gem_obj - QDA GEM buffer object + * + * This structure represents a GEM buffer object that can be either + * allocated by the driver or imported from another driver via dma-buf. + */ +struct qda_gem_obj { + /* DRM GEM object base structure */ + struct drm_gem_object base; + /* Kernel virtual address of allocated memory */ + void *virt; + /* DMA address for allocated buffers */ + dma_addr_t dma_addr; + /* Size of the buffer in bytes */ + size_t size; + /* IOMMU device that performed the allocation */ + struct qda_iommu_device *iommu_dev; +}; + +/* + * Helper macro to cast a drm_gem_object to qda_gem_obj + */ +#define to_qda_gem_obj(gem_obj) container_of(gem_obj, struct qda_gem_obj, base) + +/* + * GEM object lifecycle management + */ +struct drm_gem_object *qda_gem_create_object(struct drm_device *drm_dev, + struct qda_memory_manager *iommu_mgr, + size_t size, struct drm_file *file_priv); +void qda_gem_free_object(struct drm_gem_object *gem_obj); +int qda_gem_mmap_obj(struct drm_gem_object *gem_obj, struct vm_area_struct *vma); + +/* + * Helper functions for GEM object allocation and cleanup + * These are used internally and by the PRIME import code + */ +struct qda_gem_obj *qda_gem_alloc_object(struct drm_device *drm_dev, size_t aligned_size); +void qda_gem_cleanup_object(struct qda_gem_obj *qda_gem_obj); + +/* + * Utility functions for GEM operations + */ +struct drm_gem_object *qda_gem_lookup_object(struct drm_file *file_priv, u32 handle); +int qda_gem_create_handle(struct drm_file *file_priv, struct drm_gem_object *gem_obj, u32 *handle); + +#endif /* _QDA_GEM_H */ diff --git a/drivers/accel/qda/qda_memory_dma.c b/drivers/accel/qda/qda_memory_dma.c new file mode 100644 index 000000000000..ffdd5423c88c --- /dev/null +++ b/drivers/accel/qda/qda_memory_dma.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. +#include <linux/slab.h> +#include <linux/dma-mapping.h> +#include "qda_drv.h" +#include "qda_memory_dma.h" + +static dma_addr_t get_actual_dma_addr(struct qda_gem_obj *gem_obj) +{ + return gem_obj->dma_addr - ((u64)gem_obj->iommu_dev->sid << 32); +} + +static void setup_gem_object(struct qda_gem_obj *gem_obj, void *virt, + dma_addr_t dma_addr, struct qda_iommu_device *iommu_dev) +{ + gem_obj->virt = virt; + gem_obj->dma_addr = dma_addr; + gem_obj->iommu_dev = iommu_dev; +} + +static void cleanup_gem_object_fields(struct qda_gem_obj *gem_obj) +{ + gem_obj->virt = NULL; + gem_obj->dma_addr = 0; + gem_obj->iommu_dev = NULL; +} + +int qda_dma_alloc(struct qda_iommu_device *iommu_dev, + struct qda_gem_obj *gem_obj, size_t size) +{ + void *virt; + dma_addr_t dma_addr; + + if (!iommu_dev || !iommu_dev->dev) { + qda_err(NULL, "Invalid iommu_dev or device for DMA allocation\n"); + return -EINVAL; + } + + virt = dma_alloc_coherent(iommu_dev->dev, size, &dma_addr, GFP_KERNEL); + if (!virt) + return -ENOMEM; + + dma_addr += ((u64)iommu_dev->sid << 32); + + qda_dbg(NULL, "DMA address with SID prefix: 0x%llx (sid=%u)\n", + (u64)dma_addr, iommu_dev->sid); + + setup_gem_object(gem_obj, virt, dma_addr, iommu_dev); + + return 0; +} + +void qda_dma_free(struct qda_gem_obj *gem_obj) +{ + if (!gem_obj || !gem_obj->iommu_dev) { + qda_dbg(NULL, "Invalid gem_obj or iommu_dev for DMA free\n"); + return; + } + + qda_dbg(NULL, "DMA freeing: size=%zu, device_id=%u, dma_addr=0x%llx\n", + gem_obj->size, gem_obj->iommu_dev->id, gem_obj->dma_addr); + + dma_free_coherent(gem_obj->iommu_dev->dev, gem_obj->size, + gem_obj->virt, get_actual_dma_addr(gem_obj)); + + cleanup_gem_object_fields(gem_obj); +} + +int qda_dma_mmap(struct qda_gem_obj *gem_obj, struct vm_area_struct *vma) +{ + struct qda_iommu_device *iommu_dev; + int ret; + + if (!gem_obj || !gem_obj->virt || !gem_obj->iommu_dev || !gem_obj->iommu_dev->dev) { + qda_err(NULL, "Invalid parameters for DMA mmap\n"); + return -EINVAL; + } + + iommu_dev = gem_obj->iommu_dev; + + ret = dma_mmap_coherent(iommu_dev->dev, vma, gem_obj->virt, + get_actual_dma_addr(gem_obj), gem_obj->size); + + if (ret) + qda_err(NULL, "DMA mmap failed: size=%zu, device_id=%u, ret=%d\n", + gem_obj->size, iommu_dev->id, ret); + else + qda_dbg(NULL, "DMA mmap successful: size=%zu\n", gem_obj->size); + + return ret; +} diff --git a/drivers/accel/qda/qda_memory_dma.h b/drivers/accel/qda/qda_memory_dma.h new file mode 100644 index 000000000000..79b3c4053a82 --- /dev/null +++ b/drivers/accel/qda/qda_memory_dma.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + */ + +#ifndef _QDA_MEMORY_DMA_H +#define _QDA_MEMORY_DMA_H + +#include <linux/dma-mapping.h> +#include "qda_memory_manager.h" + +/** + * qda_dma_alloc() - Allocate DMA coherent memory for a GEM object + * @iommu_dev: Pointer to the QDA IOMMU device structure + * @gem_obj: Pointer to GEM object to allocate memory for + * @size: Size of memory to allocate in bytes + * + * Allocates DMA-coherent memory and sets up the GEM object with the + * allocated memory details including virtual and DMA addresses. + * + * Return: 0 on success, negative error code on failure + */ +int qda_dma_alloc(struct qda_iommu_device *iommu_dev, + struct qda_gem_obj *gem_obj, size_t size); + +/** + * qda_dma_free() - Free DMA coherent memory for a GEM object + * @gem_obj: Pointer to GEM object to free memory for + * + * Frees DMA-coherent memory previously allocated for the GEM object + * and cleans up the GEM object fields. + */ +void qda_dma_free(struct qda_gem_obj *gem_obj); + +/** + * qda_dma_mmap() - Map DMA memory into userspace + * @gem_obj: Pointer to GEM object containing DMA memory + * @vma: Virtual memory area to map into + * + * Maps DMA-coherent memory into userspace virtual address space. + * + * Return: 0 on success, negative error code on failure + */ +int qda_dma_mmap(struct qda_gem_obj *gem_obj, struct vm_area_struct *vma); + +#endif /* _QDA_MEMORY_DMA_H */ diff --git a/drivers/accel/qda/qda_memory_manager.c b/drivers/accel/qda/qda_memory_manager.c index b4c7047a89d4..e225667557ee 100644 --- a/drivers/accel/qda/qda_memory_manager.c +++ b/drivers/accel/qda/qda_memory_manager.c @@ -6,8 +6,11 @@ #include <linux/spinlock.h> #include <linux/workqueue.h> #include <linux/xarray.h> +#include <drm/drm_file.h> #include "qda_drv.h" +#include "qda_gem.h" #include "qda_memory_manager.h" +#include "qda_memory_dma.h" static void cleanup_all_memory_devices(struct qda_memory_manager *mem_mgr) { @@ -55,6 +58,8 @@ static void init_iommu_device_fields(struct qda_iommu_device *iommu_dev, spin_lock_init(&iommu_dev->lock); refcount_set(&iommu_dev->refcount, 0); INIT_WORK(&iommu_dev->remove_work, qda_memory_manager_remove_work); + iommu_dev->assigned_pid = 0; + iommu_dev->assigned_file_priv = NULL; } static int allocate_device_id(struct qda_memory_manager *mem_mgr, @@ -78,6 +83,194 @@ static int allocate_device_id(struct qda_memory_manager *mem_mgr, return ret; } +static struct qda_iommu_device *find_device_for_pid(struct qda_memory_manager *mem_mgr, + pid_t pid) +{ + unsigned long index; + void *entry; + struct qda_iommu_device *found_dev = NULL; + unsigned long flags; + + xa_lock(&mem_mgr->device_xa); + xa_for_each(&mem_mgr->device_xa, index, entry) { + struct qda_iommu_device *iommu_dev = entry; + + spin_lock_irqsave(&iommu_dev->lock, flags); + if (iommu_dev->assigned_pid == pid) { + found_dev = iommu_dev; + refcount_inc(&found_dev->refcount); + qda_dbg(NULL, "Reusing device id=%u for PID=%d (refcount=%u)\n", + found_dev->id, pid, refcount_read(&found_dev->refcount)); + spin_unlock_irqrestore(&iommu_dev->lock, flags); + break; + } + spin_unlock_irqrestore(&iommu_dev->lock, flags); + } + xa_unlock(&mem_mgr->device_xa); + + return found_dev; +} + +static struct qda_iommu_device *assign_available_device_to_pid(struct qda_memory_manager *mem_mgr, + pid_t pid, + struct drm_file *file_priv) +{ + unsigned long index; + void *entry; + struct qda_iommu_device *selected_dev = NULL; + unsigned long flags; + + xa_lock(&mem_mgr->device_xa); + xa_for_each(&mem_mgr->device_xa, index, entry) { + struct qda_iommu_device *iommu_dev = entry; + + spin_lock_irqsave(&iommu_dev->lock, flags); + if (iommu_dev->assigned_pid == 0) { + iommu_dev->assigned_pid = pid; + iommu_dev->assigned_file_priv = file_priv; + selected_dev = iommu_dev; + refcount_set(&selected_dev->refcount, 1); + qda_dbg(NULL, "Assigned device id=%u to PID=%d\n", + selected_dev->id, pid); + spin_unlock_irqrestore(&iommu_dev->lock, flags); + break; + } + spin_unlock_irqrestore(&iommu_dev->lock, flags); + } + xa_unlock(&mem_mgr->device_xa); + + return selected_dev; +} + +static struct qda_iommu_device *get_process_iommu_device(struct qda_memory_manager *mem_mgr, + struct drm_file *file_priv) +{ + struct qda_file_priv *qda_priv; + + if (!file_priv || !file_priv->driver_priv) + return NULL; + + qda_priv = (struct qda_file_priv *)file_priv->driver_priv; + return qda_priv->assigned_iommu_dev; +} + +static int qda_memory_manager_assign_device(struct qda_memory_manager *mem_mgr, + struct drm_file *file_priv) +{ + struct qda_file_priv *qda_priv; + struct qda_iommu_device *selected_dev = NULL; + int ret = 0; + pid_t current_pid; + + if (!file_priv || !file_priv->driver_priv) { + qda_err(NULL, "Invalid file_priv or driver_priv\n"); + return -EINVAL; + } + + qda_priv = (struct qda_file_priv *)file_priv->driver_priv; + current_pid = qda_priv->pid; + + mutex_lock(&mem_mgr->process_assignment_lock); + + if (qda_priv->assigned_iommu_dev) { + qda_dbg(NULL, "PID=%d already has device id=%u assigned\n", + current_pid, qda_priv->assigned_iommu_dev->id); + ret = 0; + goto unlock_and_return; + } + + selected_dev = find_device_for_pid(mem_mgr, current_pid); + + if (selected_dev) { + qda_priv->assigned_iommu_dev = selected_dev; + goto unlock_and_return; + } + + selected_dev = assign_available_device_to_pid(mem_mgr, current_pid, file_priv); + + if (!selected_dev) { + qda_err(NULL, "No available device for PID=%d\n", current_pid); + ret = -ENOMEM; + goto unlock_and_return; + } + + qda_priv->assigned_iommu_dev = selected_dev; + +unlock_and_return: + mutex_unlock(&mem_mgr->process_assignment_lock); + return ret; +} + +static struct qda_iommu_device *get_or_assign_iommu_device(struct qda_memory_manager *mem_mgr, + struct drm_file *file_priv, + size_t size) +{ + struct qda_iommu_device *iommu_dev; + int ret; + + iommu_dev = get_process_iommu_device(mem_mgr, file_priv); + if (iommu_dev) + return iommu_dev; + + ret = qda_memory_manager_assign_device(mem_mgr, file_priv); + if (ret) + return NULL; + + iommu_dev = get_process_iommu_device(mem_mgr, file_priv); + if (iommu_dev) + return iommu_dev; + + return NULL; +} + +int qda_memory_manager_alloc(struct qda_memory_manager *mem_mgr, struct qda_gem_obj *gem_obj, + struct drm_file *file_priv) +{ + struct qda_iommu_device *selected_dev; + size_t size; + int ret; + + if (!mem_mgr || !gem_obj || !file_priv) { + qda_err(NULL, "Invalid parameters for memory allocation\n"); + return -EINVAL; + } + + size = gem_obj->size; + if (size == 0) { + qda_err(NULL, "Invalid allocation size: 0\n"); + return -EINVAL; + } + + selected_dev = get_or_assign_iommu_device(mem_mgr, file_priv, size); + + if (!selected_dev) { + qda_err(NULL, "Failed to get/assign device for allocation (size=%zu)\n", size); + return -ENOMEM; + } + + ret = qda_dma_alloc(selected_dev, gem_obj, size); + + if (ret) { + qda_err(NULL, "Allocation failed: size=%zu, device_id=%u, ret=%d\n", + size, selected_dev->id, ret); + return ret; + } + + qda_dbg(NULL, "Successfully allocated: size=%zu, device_id=%u, dma_addr=0x%llx\n", + size, selected_dev->id, gem_obj->dma_addr); + return 0; +} + +void qda_memory_manager_free(struct qda_memory_manager *mem_mgr, struct qda_gem_obj *gem_obj) +{ + if (!gem_obj || !gem_obj->iommu_dev) { + qda_dbg(NULL, "Invalid gem_obj or iommu_dev for free\n"); + return; + } + + qda_dma_free(gem_obj); +} + int qda_memory_manager_register_device(struct qda_memory_manager *mem_mgr, struct qda_iommu_device *iommu_dev) { @@ -134,6 +327,7 @@ int qda_memory_manager_init(struct qda_memory_manager *mem_mgr) xa_init_flags(&mem_mgr->device_xa, XA_FLAGS_ALLOC); atomic_set(&mem_mgr->next_id, 0); + mutex_init(&mem_mgr->process_assignment_lock); mem_mgr->wq = create_workqueue("memory_manager_wq"); if (!mem_mgr->wq) { qda_err(NULL, "Failed to create memory manager workqueue\n"); diff --git a/drivers/accel/qda/qda_memory_manager.h b/drivers/accel/qda/qda_memory_manager.h index 3bf4cd529909..bac44284ef98 100644 --- a/drivers/accel/qda/qda_memory_manager.h +++ b/drivers/accel/qda/qda_memory_manager.h @@ -11,6 +11,8 @@ #include <linux/spinlock.h> #include <linux/workqueue.h> #include <linux/xarray.h> +#include <drm/drm_file.h> +#include "qda_gem.h" /** * struct qda_iommu_device - IOMMU device instance for memory management @@ -35,6 +37,10 @@ struct qda_iommu_device { u32 sid; /* Pointer to parent memory manager */ struct qda_memory_manager *manager; + /* Process ID of the process assigned to this device */ + pid_t assigned_pid; + /* DRM file private data for the assigned process */ + struct drm_file *assigned_file_priv; }; /** @@ -51,6 +57,8 @@ struct qda_memory_manager { atomic_t next_id; /* Workqueue for asynchronous device operations */ struct workqueue_struct *wq; + /* Mutex protecting process-to-device assignments */ + struct mutex process_assignment_lock; }; /** @@ -98,4 +106,29 @@ int qda_memory_manager_register_device(struct qda_memory_manager *mem_mgr, void qda_memory_manager_unregister_device(struct qda_memory_manager *mem_mgr, struct qda_iommu_device *iommu_dev); +/** + * qda_memory_manager_alloc() - Allocate memory for a GEM object + * @mem_mgr: Pointer to memory manager + * @gem_obj: Pointer to GEM object to allocate memory for + * @file_priv: DRM file private data for process association + * + * Allocates memory for the specified GEM object using an appropriate IOMMU + * device. The allocation is associated with the calling process via + * file_priv. + * + * Return: 0 on success, negative error code on failure + */ +int qda_memory_manager_alloc(struct qda_memory_manager *mem_mgr, struct qda_gem_obj *gem_obj, + struct drm_file *file_priv); + +/** + * qda_memory_manager_free() - Free memory for a GEM object + * @mem_mgr: Pointer to memory manager + * @gem_obj: Pointer to GEM object to free memory for + * + * Releases memory previously allocated for the specified GEM object and + * removes any associated IOMMU mappings. + */ +void qda_memory_manager_free(struct qda_memory_manager *mem_mgr, struct qda_gem_obj *gem_obj); + #endif /* _QDA_MEMORY_MANAGER_H */ -- 2.34.1
