/* * Copyright © 2008 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (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 (including the next * paragraph) 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. * * Authors: * Eric Anholt <eric@anholt.net> * */ #include <linux/dma-buf.h>#include <linux/export.h>#include <linux/file.h>#include <linux/fs.h>#ifdef CONFIG_TRANSPARENT_HUGEPAGE#include <linux/fs_context.h>#endif#include <linux/iosys-map.h>#include <linux/mem_encrypt.h>#include <linux/mm.h>#include <linux/mman.h>#include <linux/module.h>#include <linux/pagemap.h>#include <linux/folio_batch.h>#include <linux/sched/mm.h>#include <linux/shmem_fs.h>#include <linux/slab.h>#include <linux/string_helpers.h>#include <linux/types.h>#include <linux/uaccess.h> #include <drm/drm.h>#include <drm/drm_device.h>#include <drm/drm_drv.h>#include <drm/drm_file.h>#include <drm/drm_gem.h>#include <drm/drm_managed.h>#include <drm/drm_print.h>#include <drm/drm_vma_manager.h> #include "drm_internal.h" /** @file drm_gem.c * * This file provides some of the base ioctls and library routines for * the graphics memory manager implemented by each device driver. * * Because various devices have different requirements in terms of * synchronization and migration strategies, implementing that is left up to * the driver, and all that the general API provides should be generic -- * allocating objects, reading/writing data with the cpu, freeing objects. * Even there, platform-dependent optimizations for reading/writing data with * the CPU mean we'll likely hook those out to driver-specific calls. However, * the DRI2 implementation wants to have at least allocate/mmap be generic. * * The goal was to have swap-backed object allocation managed through * struct file. However, file descriptors as handles to a struct file have * two major failings: * - Process limits prevent more than 1024 or so being used at a time by * default. * - Inability to allocate high fds will aggravate the X Server's select() * handling, and likely that of many GL client applications as well. * * This led to a plan of using our own integer IDs (called handles, following * DRM terminology) to mimic fds, and implement the fd syscalls we need as * ioctls. The objects themselves will still include the struct file so * that we can transition to fds if the required kernel infrastructure shows * up at a later date, and as our interface with shmfs for memory allocation. */ #ifdef CONFIG_TRANSPARENT_HUGEPAGEstatic void drm_gem_huge_mnt_free(struct drm_device *dev, void *data){ kern_unmount(dev->huge_mnt);} /** * drm_gem_huge_mnt_create - Create, mount and use a huge tmpfs mountpoint * @dev: DRM device that will use the huge tmpfs mountpoint * @value: huge tmpfs mount option value * * This function creates and mounts a dedicated huge tmpfs mountpoint for the * lifetime of the DRM device @dev which is used at GEM object initialization * with drm_gem_object_init(). * * The most common option for @value is "within_size" which only allocates huge * pages if the page will be fully within the GEM object size. "always", * "advise" and "never" are supported too but the latter would just create a * mountpoint similar to the default one (`shm_mnt`). See shmemfs and * Transparent Hugepage for more information. * * Returns: * 0 on success or a negative error code on failure. */int drm_gem_huge_mnt_create(struct drm_device *dev, const char *value){ struct file_system_type *type; struct fs_context *fc; int ret; if (unlikely(drm_gem_get_huge_mnt(dev))) return 0; type = get_fs_type("tmpfs"); if (unlikely(!type)) return -EOPNOTSUPP; fc = fs_context_for_mount(type, SB_KERNMOUNT); if (IS_ERR(fc)) return PTR_ERR(fc); ret = vfs_parse_fs_string(fc, "source", "tmpfs"); if (unlikely(ret)) return -ENOPARAM; ret = vfs_parse_fs_string(fc, "huge", value); if (unlikely(ret)) return -ENOPARAM; dev->huge_mnt = fc_mount_longterm(fc); put_fs_context(fc); return drmm_add_action_or_reset(dev, drm_gem_huge_mnt_free, NULL);}EXPORT_SYMBOL_GPL(drm_gem_huge_mnt_create);#endif static voiddrm_gem_init_release(struct drm_device *dev, void *ptr){ drm_vma_offset_manager_destroy(dev->vma_offset_manager);} /** * drm_gem_init - Initialize the GEM device fields * @dev: drm_devic structure to initialize */intdrm_gem_init(struct drm_device *dev){ struct drm_vma_offset_manager *vma_offset_manager; mutex_init(&dev->object_name_lock); idr_init_base(&dev->object_name_idr, 1); vma_offset_manager = drmm_kzalloc(dev, sizeof(*vma_offset_manager), GFP_KERNEL); if (!vma_offset_manager) return -ENOMEM; dev->vma_offset_manager = vma_offset_manager; drm_vma_offset_manager_init(vma_offset_manager, DRM_FILE_PAGE_OFFSET_START, DRM_FILE_PAGE_OFFSET_SIZE); return drmm_add_action(dev, drm_gem_init_release, NULL);} /** * drm_gem_object_init - initialize an allocated shmem-backed GEM object * * @dev: drm_device the object should be initialized for * @obj: drm_gem_object to initialize * @size: object size * * Initialize an already allocated GEM object of the specified size with * shmfs backing store. A huge mountpoint can be used by calling * drm_gem_huge_mnt_create() beforehand. */int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size){ struct vfsmount *huge_mnt; struct file *filp; const vma_flags_t flags = mk_vma_flags(VMA_NORESERVE_BIT); drm_gem_private_object_init(dev, obj, size); huge_mnt = drm_gem_get_huge_mnt(dev); if (huge_mnt) filp = shmem_file_setup_with_mnt(huge_mnt, "drm mm object", size, flags); else filp = shmem_file_setup("drm mm object", size, flags); if (IS_ERR(filp)) return PTR_ERR(filp); obj->filp = filp; return 0;}EXPORT_SYMBOL(drm_gem_object_init); /** * drm_gem_private_object_init - initialize an allocated private GEM object * @dev: drm_device the object should be initialized for * @obj: drm_gem_object to initialize * @size: object size * * Initialize an already allocated GEM object of the specified size with * no GEM provided backing store. Instead the caller is responsible for * backing the object and handling it. */void drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size){ BUG_ON((size & (PAGE_SIZE - 1)) != 0); obj->dev = dev; obj->filp = NULL; kref_init(&obj->refcount); obj->handle_count = 0; obj->size = size; mutex_init(&obj->gpuva.lock); dma_resv_init(&obj->_resv); if (!obj->resv) obj->resv = &obj->_resv; drm_gem_gpuva_init(obj); drm_vma_node_reset(&obj->vma_node); INIT_LIST_HEAD(&obj->lru_node);}EXPORT_SYMBOL(drm_gem_private_object_init); /** * drm_gem_private_object_fini - Finalize a failed drm_gem_object * @obj: drm_gem_object * * Uninitialize an already allocated GEM object when it initialized failed */void drm_gem_private_object_fini(struct drm_gem_object *obj){ WARN_ON(obj->dma_buf); dma_resv_fini(&obj->_resv); mutex_destroy(&obj->gpuva.lock);}EXPORT_SYMBOL(drm_gem_private_object_fini); static void drm_gem_object_handle_get(struct drm_gem_object *obj){ struct drm_device *dev = obj->dev; drm_WARN_ON(dev, !mutex_is_locked(&dev->object_name_lock)); if (obj->handle_count++ == 0) drm_gem_object_get(obj);} /** * drm_gem_object_handle_get_if_exists_unlocked - acquire reference on user-space handle, if any * @obj: GEM object * * Acquires a reference on the GEM buffer object's handle. Required to keep * the GEM object alive. Call drm_gem_object_handle_put_if_exists_unlocked() * to release the reference. Does nothing if the buffer object has no handle. * * Returns: * True if a handle exists, or false otherwise */bool drm_gem_object_handle_get_if_exists_unlocked(struct drm_gem_object *obj){ struct drm_device *dev = obj->dev; guard(mutex)(&dev->object_name_lock); /* * First ref taken during GEM object creation, if any. Some * drivers set up internal framebuffers with GEM objects that * do not have a GEM handle. Hence, this counter can be zero. */ if (!obj->handle_count) return false; drm_gem_object_handle_get(obj); return true;} /** * drm_gem_object_handle_free - release resources bound to userspace handles * @obj: GEM object to clean up. * * Called after the last handle to the object has been closed * * Removes any name for the object. Note that this must be * called before drm_gem_object_free or we'll be touching * freed memory */static void drm_gem_object_handle_free(struct drm_gem_object *obj){ struct drm_device *dev = obj->dev; /* Remove any name for this object */ if (obj->name) { idr_remove(&dev->object_name_idr, obj->name); obj->name = 0; }} static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj){ /* Unbreak the reference cycle if we have an exported dma_buf. */ if (obj->dma_buf) { dma_buf_put(obj->dma_buf); obj->dma_buf = NULL; }} /** * drm_gem_object_handle_put_unlocked - releases reference on user-space handle * @obj: GEM object * * Releases a reference on the GEM buffer object's handle. Possibly releases * the GEM buffer object and associated dma-buf objects. */void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj){ struct drm_device *dev = obj->dev; bool final = false; if (drm_WARN_ON(dev, READ_ONCE(obj->handle_count) == 0)) return; /* * Must bump handle count first as this may be the last * ref, in which case the object would disappear before * we checked for a name. */ mutex_lock(&dev->object_name_lock); if (--obj->handle_count == 0) { drm_gem_object_handle_free(obj); drm_gem_object_exported_dma_buf_free(obj); final = true; } mutex_unlock(&dev->object_name_lock); if (final) drm_gem_object_put(obj);} /* * Called at device or object close to release the file's * handle references on objects. */static intdrm_gem_object_release_handle(int id, void *ptr, void *data){ struct drm_file *file_priv = data; struct drm_gem_object *obj = ptr; if (drm_WARN_ON(obj->dev, !data)) return 0; if (obj->funcs->close) obj->funcs->close(obj, file_priv); mutex_lock(&file_priv->prime.lock); drm_prime_remove_buf_handle(&file_priv->prime, id); mutex_unlock(&file_priv->prime.lock); drm_vma_node_revoke(&obj->vma_node, file_priv); drm_gem_object_handle_put_unlocked(obj); return 0;} /** * drm_gem_handle_delete - deletes the given file-private handle * @filp: drm file-private structure to use for the handle look up * @handle: userspace handle to delete * * Removes the GEM handle from the @filp lookup table which has been added with * drm_gem_handle_create(). If this is the last handle also cleans up linked * resources like GEM names. */intdrm_gem_handle_delete(struct drm_file *filp, u32 handle){ struct drm_gem_object *obj; spin_lock(&filp->table_lock); /* Check if we currently have a reference on the object */ obj = idr_replace(&filp->object_idr, NULL, handle); spin_unlock(&filp->table_lock); if (IS_ERR_OR_NULL(obj)) return -EINVAL; /* Release driver's reference and decrement refcount. */ drm_gem_object_release_handle(handle, obj, filp); /* And finally make the handle available for future allocations. */ spin_lock(&filp->table_lock); idr_remove(&filp->object_idr, handle); spin_unlock(&filp->table_lock); return 0;}EXPORT_SYMBOL(drm_gem_handle_delete); /** * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object * @file: drm file-private structure containing the gem object * @dev: corresponding drm_device * @handle: gem object handle * @offset: return location for the fake mmap offset * * This implements the &drm_driver.dumb_map_offset kms driver callback for * drivers which use gem to manage their backing storage. * * Returns: * 0 on success or a negative error code on failure. */int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, u32 handle, u64 *offset){ struct drm_gem_object *obj; int ret; obj = drm_gem_object_lookup(file, handle); if (!obj) return -ENOENT; /* Don't allow imported objects to be mapped */ if (drm_gem_is_imported(obj)) { ret = -EINVAL; goto out; } ret = drm_gem_create_mmap_offset(obj); if (ret) goto out; *offset = drm_vma_node_offset_addr(&obj->vma_node);out: drm_gem_object_put(obj); return ret;}EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset); /** * drm_gem_handle_create_tail - internal functions to create a handle * @file_priv: drm file-private structure to register the handle for * @obj: object to register * @handlep: pointer to return the created handle to the caller * * This expects the &drm_device.object_name_lock to be held already and will * drop it before returning. Used to avoid races in establishing new handles * when importing an object from either an flink name or a dma-buf. * * Handles must be release again through drm_gem_handle_delete(). This is done * when userspace closes @file_priv for all attached handles, or through the * GEM_CLOSE ioctl for individual handles. */intdrm_gem_handle_create_tail(struct drm_file *file_priv, struct drm_gem_object *obj, u32 *handlep){ struct drm_device *dev = obj->dev; u32 handle; int ret; WARN_ON(!mutex_is_locked(&dev->object_name_lock)); drm_gem_object_handle_get(obj); /* * Get the user-visible handle using idr. Preload and perform * allocation under our spinlock. */ idr_preload(GFP_KERNEL); spin_lock(&file_priv->table_lock); ret = idr_alloc(&file_priv->object_idr, NULL, 1, 0, GFP_NOWAIT); spin_unlock(&file_priv->table_lock);Lines 1–500 of 1768. Load more
/* * Copyright © 2008 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (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 (including the next * paragraph) 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. * * Authors: * Eric Anholt <eric@anholt.net> * */ #include <linux/dma-buf.h> #include <linux/export.h> #include <linux/file.h> #include <linux/fs.h> #ifdef CONFIG_TRANSPARENT_HUGEPAGE #include <linux/fs_context.h> #endif #include <linux/iosys-map.h> #include <linux/mem_encrypt.h> #include <linux/mm.h> #include <linux/mman.h> #include <linux/module.h> #include <linux/pagemap.h> #include <linux/folio_batch.h> #include <linux/sched/mm.h> #include <linux/shmem_fs.h> #include <linux/slab.h> #include <linux/string_helpers.h> #include <linux/types.h> #include <linux/uaccess.h> #include <drm/drm.h> #include <drm/drm_device.h> #include <drm/drm_drv.h> #include <drm/drm_file.h> #include <drm/drm_gem.h> #include <drm/drm_managed.h> #include <drm/drm_print.h> #include <drm/drm_vma_manager.h> #include "drm_internal.h" /** @file drm_gem.c * * This file provides some of the base ioctls and library routines for * the graphics memory manager implemented by each device driver. * * Because various devices have different requirements in terms of * synchronization and migration strategies, implementing that is left up to * the driver, and all that the general API provides should be generic -- * allocating objects, reading/writing data with the cpu, freeing objects. * Even there, platform-dependent optimizations for reading/writing data with * the CPU mean we'll likely hook those out to driver-specific calls. However, * the DRI2 implementation wants to have at least allocate/mmap be generic. * * The goal was to have swap-backed object allocation managed through * struct file. However, file descriptors as handles to a struct file have * two major failings: * - Process limits prevent more than 1024 or so being used at a time by * default. * - Inability to allocate high fds will aggravate the X Server's select() * handling, and likely that of many GL client applications as well. * * This led to a plan of using our own integer IDs (called handles, following * DRM terminology) to mimic fds, and implement the fd syscalls we need as * ioctls. The objects themselves will still include the struct file so * that we can transition to fds if the required kernel infrastructure shows * up at a later date, and as our interface with shmfs for memory allocation. */ #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void drm_gem_huge_mnt_free(struct drm_device *dev, void *data) { kern_unmount(dev->huge_mnt); } /** * drm_gem_huge_mnt_create - Create, mount and use a huge tmpfs mountpoint * @dev: DRM device that will use the huge tmpfs mountpoint * @value: huge tmpfs mount option value * * This function creates and mounts a dedicated huge tmpfs mountpoint for the * lifetime of the DRM device @dev which is used at GEM object initialization * with drm_gem_object_init(). * * The most common option for @value is "within_size" which only allocates huge * pages if the page will be fully within the GEM object size. "always", * "advise" and "never" are supported too but the latter would just create a * mountpoint similar to the default one (`shm_mnt`). See shmemfs and * Transparent Hugepage for more information. * * Returns: * 0 on success or a negative error code on failure. */ int drm_gem_huge_mnt_create(struct drm_device *dev, const char *value) { struct file_system_type *type; struct fs_context *fc; int ret; if (unlikely(drm_gem_get_huge_mnt(dev))) return 0; type = get_fs_type("tmpfs"); if (unlikely(!type)) return -EOPNOTSUPP; fc = fs_context_for_mount(type, SB_KERNMOUNT); if (IS_ERR(fc)) return PTR_ERR(fc); ret = vfs_parse_fs_string(fc, "source", "tmpfs"); if (unlikely(ret)) return -ENOPARAM; ret = vfs_parse_fs_string(fc, "huge", value); if (unlikely(ret)) return -ENOPARAM; dev->huge_mnt = fc_mount_longterm(fc); put_fs_context(fc); return drmm_add_action_or_reset(dev, drm_gem_huge_mnt_free, NULL); } EXPORT_SYMBOL_GPL(drm_gem_huge_mnt_create); #endif static void drm_gem_init_release(struct drm_device *dev, void *ptr) { drm_vma_offset_manager_destroy(dev->vma_offset_manager); } /** * drm_gem_init - Initialize the GEM device fields * @dev: drm_devic structure to initialize */ int drm_gem_init(struct drm_device *dev) { struct drm_vma_offset_manager *vma_offset_manager; mutex_init(&dev->object_name_lock); idr_init_base(&dev->object_name_idr, 1); vma_offset_manager = drmm_kzalloc(dev, sizeof(*vma_offset_manager), GFP_KERNEL); if (!vma_offset_manager) return -ENOMEM; dev->vma_offset_manager = vma_offset_manager; drm_vma_offset_manager_init(vma_offset_manager, DRM_FILE_PAGE_OFFSET_START, DRM_FILE_PAGE_OFFSET_SIZE); return drmm_add_action(dev, drm_gem_init_release, NULL); } /** * drm_gem_object_init - initialize an allocated shmem-backed GEM object * * @dev: drm_device the object should be initialized for * @obj: drm_gem_object to initialize * @size: object size * * Initialize an already allocated GEM object of the specified size with * shmfs backing store. A huge mountpoint can be used by calling * drm_gem_huge_mnt_create() beforehand. */ int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size) { struct vfsmount *huge_mnt; struct file *filp; const vma_flags_t flags = mk_vma_flags(VMA_NORESERVE_BIT); drm_gem_private_object_init(dev, obj, size); huge_mnt = drm_gem_get_huge_mnt(dev); if (huge_mnt) filp = shmem_file_setup_with_mnt(huge_mnt, "drm mm object", size, flags); else filp = shmem_file_setup("drm mm object", size, flags); if (IS_ERR(filp)) return PTR_ERR(filp); obj->filp = filp; return 0; } EXPORT_SYMBOL(drm_gem_object_init); /** * drm_gem_private_object_init - initialize an allocated private GEM object * @dev: drm_device the object should be initialized for * @obj: drm_gem_object to initialize * @size: object size * * Initialize an already allocated GEM object of the specified size with * no GEM provided backing store. Instead the caller is responsible for * backing the object and handling it. */ void drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size) { BUG_ON((size & (PAGE_SIZE - 1)) != 0); obj->dev = dev; obj->filp = NULL; kref_init(&obj->refcount); obj->handle_count = 0; obj->size = size; mutex_init(&obj->gpuva.lock); dma_resv_init(&obj->_resv); if (!obj->resv) obj->resv = &obj->_resv; drm_gem_gpuva_init(obj); drm_vma_node_reset(&obj->vma_node); INIT_LIST_HEAD(&obj->lru_node); } EXPORT_SYMBOL(drm_gem_private_object_init); /** * drm_gem_private_object_fini - Finalize a failed drm_gem_object * @obj: drm_gem_object * * Uninitialize an already allocated GEM object when it initialized failed */ void drm_gem_private_object_fini(struct drm_gem_object *obj) { WARN_ON(obj->dma_buf); dma_resv_fini(&obj->_resv); mutex_destroy(&obj->gpuva.lock); } EXPORT_SYMBOL(drm_gem_private_object_fini); static void drm_gem_object_handle_get(struct drm_gem_object *obj) { struct drm_device *dev = obj->dev; drm_WARN_ON(dev, !mutex_is_locked(&dev->object_name_lock)); if (obj->handle_count++ == 0) drm_gem_object_get(obj); } /** * drm_gem_object_handle_get_if_exists_unlocked - acquire reference on user-space handle, if any * @obj: GEM object * * Acquires a reference on the GEM buffer object's handle. Required to keep * the GEM object alive. Call drm_gem_object_handle_put_if_exists_unlocked() * to release the reference. Does nothing if the buffer object has no handle. * * Returns: * True if a handle exists, or false otherwise */ bool drm_gem_object_handle_get_if_exists_unlocked(struct drm_gem_object *obj) { struct drm_device *dev = obj->dev; guard(mutex)(&dev->object_name_lock); /* * First ref taken during GEM object creation, if any. Some * drivers set up internal framebuffers with GEM objects that * do not have a GEM handle. Hence, this counter can be zero. */ if (!obj->handle_count) return false; drm_gem_object_handle_get(obj); return true; } /** * drm_gem_object_handle_free - release resources bound to userspace handles * @obj: GEM object to clean up. * * Called after the last handle to the object has been closed * * Removes any name for the object. Note that this must be * called before drm_gem_object_free or we'll be touching * freed memory */ static void drm_gem_object_handle_free(struct drm_gem_object *obj) { struct drm_device *dev = obj->dev; /* Remove any name for this object */ if (obj->name) { idr_remove(&dev->object_name_idr, obj->name); obj->name = 0; } } static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) { /* Unbreak the reference cycle if we have an exported dma_buf. */ if (obj->dma_buf) { dma_buf_put(obj->dma_buf); obj->dma_buf = NULL; } } /** * drm_gem_object_handle_put_unlocked - releases reference on user-space handle * @obj: GEM object * * Releases a reference on the GEM buffer object's handle. Possibly releases * the GEM buffer object and associated dma-buf objects. */ void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj) { struct drm_device *dev = obj->dev; bool final = false; if (drm_WARN_ON(dev, READ_ONCE(obj->handle_count) == 0)) return; /* * Must bump handle count first as this may be the last * ref, in which case the object would disappear before * we checked for a name. */ mutex_lock(&dev->object_name_lock); if (--obj->handle_count == 0) { drm_gem_object_handle_free(obj); drm_gem_object_exported_dma_buf_free(obj); final = true; } mutex_unlock(&dev->object_name_lock); if (final) drm_gem_object_put(obj); } /* * Called at device or object close to release the file's * handle references on objects. */ static int drm_gem_object_release_handle(int id, void *ptr, void *data) { struct drm_file *file_priv = data; struct drm_gem_object *obj = ptr; if (drm_WARN_ON(obj->dev, !data)) return 0; if (obj->funcs->close) obj->funcs->close(obj, file_priv); mutex_lock(&file_priv->prime.lock); drm_prime_remove_buf_handle(&file_priv->prime, id); mutex_unlock(&file_priv->prime.lock); drm_vma_node_revoke(&obj->vma_node, file_priv); drm_gem_object_handle_put_unlocked(obj); return 0; } /** * drm_gem_handle_delete - deletes the given file-private handle * @filp: drm file-private structure to use for the handle look up * @handle: userspace handle to delete * * Removes the GEM handle from the @filp lookup table which has been added with * drm_gem_handle_create(). If this is the last handle also cleans up linked * resources like GEM names. */ int drm_gem_handle_delete(struct drm_file *filp, u32 handle) { struct drm_gem_object *obj; spin_lock(&filp->table_lock); /* Check if we currently have a reference on the object */ obj = idr_replace(&filp->object_idr, NULL, handle); spin_unlock(&filp->table_lock); if (IS_ERR_OR_NULL(obj)) return -EINVAL; /* Release driver's reference and decrement refcount. */ drm_gem_object_release_handle(handle, obj, filp); /* And finally make the handle available for future allocations. */ spin_lock(&filp->table_lock); idr_remove(&filp->object_idr, handle); spin_unlock(&filp->table_lock); return 0; } EXPORT_SYMBOL(drm_gem_handle_delete); /** * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object * @file: drm file-private structure containing the gem object * @dev: corresponding drm_device * @handle: gem object handle * @offset: return location for the fake mmap offset * * This implements the &drm_driver.dumb_map_offset kms driver callback for * drivers which use gem to manage their backing storage. * * Returns: * 0 on success or a negative error code on failure. */ int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, u32 handle, u64 *offset) { struct drm_gem_object *obj; int ret; obj = drm_gem_object_lookup(file, handle); if (!obj) return -ENOENT; /* Don't allow imported objects to be mapped */ if (drm_gem_is_imported(obj)) { ret = -EINVAL; goto out; } ret = drm_gem_create_mmap_offset(obj); if (ret) goto out; *offset = drm_vma_node_offset_addr(&obj->vma_node); out: drm_gem_object_put(obj); return ret; } EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset); /** * drm_gem_handle_create_tail - internal functions to create a handle * @file_priv: drm file-private structure to register the handle for * @obj: object to register * @handlep: pointer to return the created handle to the caller * * This expects the &drm_device.object_name_lock to be held already and will * drop it before returning. Used to avoid races in establishing new handles * when importing an object from either an flink name or a dma-buf. * * Handles must be release again through drm_gem_handle_delete(). This is done * when userspace closes @file_priv for all attached handles, or through the * GEM_CLOSE ioctl for individual handles. */ int drm_gem_handle_create_tail(struct drm_file *file_priv, struct drm_gem_object *obj, u32 *handlep) { struct drm_device *dev = obj->dev; u32 handle; int ret; WARN_ON(!mutex_is_locked(&dev->object_name_lock)); drm_gem_object_handle_get(obj); /* * Get the user-visible handle using idr. Preload and perform * allocation under our spinlock. */ idr_preload(GFP_KERNEL); spin_lock(&file_priv->table_lock); ret = idr_alloc(&file_priv->object_idr, NULL, 1, 0, GFP_NOWAIT); spin_unlock(&file_priv->table_lock);