Use device file descriptors and regions to represent pagemaps on foreign or local devices.
The underlying files are type-checked at madvise time, and references are kept on the drm_pagemap as long as there is are madvises pointing to it. Extend the madvise preferred_location UAPI to support the region instance to identify the foreign placement. v2: - Improve UAPI documentation. (Matt Brost) - Sanitize preferred_mem_loc.region_instance madvise. (Matt Brost) - Clarify madvise drm_pagemap vs xe_pagemap refcounting. (Matt Brost) - Don't allow a foreign drm_pagemap madvise without a fast interconnect. Signed-off-by: Thomas Hellström <[email protected]> --- drivers/gpu/drm/xe/xe_device.c | 14 +++++ drivers/gpu/drm/xe/xe_device.h | 2 + drivers/gpu/drm/xe/xe_svm.c | 78 +++++++++++++++++++++++++++ drivers/gpu/drm/xe/xe_svm.h | 7 +++ drivers/gpu/drm/xe/xe_vm_madvise.c | 86 ++++++++++++++++++++++++++---- include/uapi/drm/xe_drm.h | 18 +++++-- 6 files changed, 191 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index ff598d0c68d7..2465c7a9a63e 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -373,6 +373,20 @@ static const struct file_operations xe_driver_fops = { .fop_flags = FOP_UNSIGNED_OFFSET, }; +/** + * xe_is_xe_file() - Is the file an xe device file? + * @file: The file. + * + * Checks whether the file is opened against + * an xe device. + * + * Return: %true if an xe file, %false if not. + */ +bool xe_is_xe_file(const struct file *file) +{ + return file->f_op == &xe_driver_fops; +} + static struct drm_driver driver = { /* Don't use MTRRs here; the Xserver or userspace app should * deal with them for Intel hardware. diff --git a/drivers/gpu/drm/xe/xe_device.h b/drivers/gpu/drm/xe/xe_device.h index 32cc6323b7f6..475e2245c955 100644 --- a/drivers/gpu/drm/xe/xe_device.h +++ b/drivers/gpu/drm/xe/xe_device.h @@ -195,6 +195,8 @@ void xe_file_put(struct xe_file *xef); int xe_is_injection_active(void); +bool xe_is_xe_file(const struct file *file); + /* * Occasionally it is seen that the G2H worker starts running after a delay of more than * a second even after being queued and activated by the Linux workqueue subsystem. This diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c index 006de141dfa7..c0b17b548a00 100644 --- a/drivers/gpu/drm/xe/xe_svm.c +++ b/drivers/gpu/drm/xe/xe_svm.c @@ -1788,6 +1788,78 @@ int xe_pagemap_cache_create(struct xe_tile *tile) return 0; } +static struct drm_pagemap *xe_devmem_open(struct xe_device *xe, u32 region_instance) +{ + u32 tile_id = region_instance - 1; + struct xe_pagemap *xpagemap; + struct drm_pagemap *dpagemap; + struct xe_vram_region *vr; + + if (tile_id >= xe->info.tile_count) + return ERR_PTR(-ENOENT); + + if (!((BIT(tile_id) << 1) & xe->info.mem_region_mask)) + return ERR_PTR(-ENOENT); + + vr = xe_tile_to_vr(&xe->tiles[tile_id]); + xpagemap = xe_pagemap_find_or_create(xe, vr->dpagemap_cache, vr); + if (IS_ERR(xpagemap)) + return ERR_CAST(xpagemap); + + /* Below is for clarity only. The reference counter is the same. */ + dpagemap = drm_pagemap_get(&xpagemap->dpagemap); + xe_pagemap_put(xpagemap); + + return dpagemap; +} + +/** + * xe_drm_pagemap_from_fd() - Return a drm_pagemap pointer from a + * (file_descriptor, region_instance) pair. + * @fd: An fd opened against an xe device. + * @region_instance: The region instance representing the device memory + * on the opened xe device. + * + * Opens a struct drm_pagemap pointer on the + * indicated device and region_instance. + * + * Return: A reference-counted struct drm_pagemap pointer on success, + * negative error pointer on failure. + */ +struct drm_pagemap *xe_drm_pagemap_from_fd(int fd, u32 region_instance) +{ + struct drm_pagemap *dpagemap; + struct file *file; + struct drm_file *fpriv; + struct drm_device *drm; + int idx; + + if (fd <= 0) + return ERR_PTR(-EINVAL); + + file = fget(fd); + if (!file) + return ERR_PTR(-ENOENT); + + if (!xe_is_xe_file(file)) { + dpagemap = ERR_PTR(-ENOENT); + goto out; + } + + fpriv = file->private_data; + drm = fpriv->minor->dev; + if (!drm_dev_enter(drm, &idx)) { + dpagemap = ERR_PTR(-ENODEV); + goto out; + } + + dpagemap = xe_devmem_open(to_xe_device(drm), region_instance); + drm_dev_exit(idx); +out: + fput(file); + return dpagemap; +} + #else int xe_pagemap_shrinker_create(struct xe_device *xe) @@ -1811,6 +1883,12 @@ struct drm_pagemap *xe_vma_resolve_pagemap(struct xe_vma *vma, struct xe_tile *t { return NULL; } + +struct drm_pagemap *xe_drm_pagemap_from_fd(int fd, u32 region_instance) +{ + return ERR_PTR(-ENOENT); +} + #endif /** diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h index a0ec173c6bf0..60eae01a4220 100644 --- a/drivers/gpu/drm/xe/xe_svm.h +++ b/drivers/gpu/drm/xe/xe_svm.h @@ -187,6 +187,8 @@ int xe_pagemap_shrinker_create(struct xe_device *xe); int xe_pagemap_cache_create(struct xe_tile *tile); +struct drm_pagemap *xe_drm_pagemap_from_fd(int fd, u32 region_instance); + #else #include <linux/interval_tree.h> #include "xe_vm.h" @@ -378,6 +380,11 @@ static inline int xe_pagemap_cache_create(struct xe_tile *tile) return 0; } +static inline struct drm_pagemap *xe_drm_pagemap_from_fd(int fd, u32 region_instance) +{ + return ERR_PTR(-ENOENT); +} + #define xe_svm_range_has_dma_mapping(...) false #endif /* CONFIG_DRM_XE_GPUSVM */ diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.c b/drivers/gpu/drm/xe/xe_vm_madvise.c index d6f47c8e146d..add9a6ca2390 100644 --- a/drivers/gpu/drm/xe/xe_vm_madvise.c +++ b/drivers/gpu/drm/xe/xe_vm_madvise.c @@ -22,6 +22,19 @@ struct xe_vmas_in_madvise_range { bool has_svm_userptr_vmas; }; +/** + * struct xe_madvise_details - Argument to madvise_funcs + * @dpagemap: Reference-counted pointer to a struct drm_pagemap. + * + * The madvise IOCTL handler may, in addition to the user-space + * args, have additional info to pass into the madvise_func that + * handles the madvise type. Use a struct_xe_madvise_details + * for that and extend the struct as necessary. + */ +struct xe_madvise_details { + struct drm_pagemap *dpagemap; +}; + static int get_vmas(struct xe_vm *vm, struct xe_vmas_in_madvise_range *madvise_range) { u64 addr = madvise_range->addr; @@ -74,7 +87,8 @@ static int get_vmas(struct xe_vm *vm, struct xe_vmas_in_madvise_range *madvise_r static void madvise_preferred_mem_loc(struct xe_device *xe, struct xe_vm *vm, struct xe_vma **vmas, int num_vmas, - struct drm_xe_madvise *op) + struct drm_xe_madvise *op, + struct xe_madvise_details *details) { int i; @@ -96,14 +110,18 @@ static void madvise_preferred_mem_loc(struct xe_device *xe, struct xe_vm *vm, * is of no use and can be ignored. */ loc->migration_policy = op->preferred_mem_loc.migration_policy; + drm_pagemap_put(loc->dpagemap); loc->dpagemap = NULL; + if (details->dpagemap) + loc->dpagemap = drm_pagemap_get(details->dpagemap); } } } static void madvise_atomic(struct xe_device *xe, struct xe_vm *vm, struct xe_vma **vmas, int num_vmas, - struct drm_xe_madvise *op) + struct drm_xe_madvise *op, + struct xe_madvise_details *details) { struct xe_bo *bo; int i; @@ -144,7 +162,8 @@ static void madvise_atomic(struct xe_device *xe, struct xe_vm *vm, static void madvise_pat_index(struct xe_device *xe, struct xe_vm *vm, struct xe_vma **vmas, int num_vmas, - struct drm_xe_madvise *op) + struct drm_xe_madvise *op, + struct xe_madvise_details *details) { int i; @@ -162,7 +181,8 @@ static void madvise_pat_index(struct xe_device *xe, struct xe_vm *vm, typedef void (*madvise_func)(struct xe_device *xe, struct xe_vm *vm, struct xe_vma **vmas, int num_vmas, - struct drm_xe_madvise *op); + struct drm_xe_madvise *op, + struct xe_madvise_details *details); static const madvise_func madvise_funcs[] = { [DRM_XE_MEM_RANGE_ATTR_PREFERRED_LOC] = madvise_preferred_mem_loc, @@ -246,11 +266,12 @@ static bool madvise_args_are_sane(struct xe_device *xe, const struct drm_xe_madv if (XE_IOCTL_DBG(xe, fd < DRM_XE_PREFERRED_LOC_DEFAULT_SYSTEM)) return false; - if (XE_IOCTL_DBG(xe, args->preferred_mem_loc.migration_policy > - DRM_XE_MIGRATE_ONLY_SYSTEM_PAGES)) + if (XE_IOCTL_DBG(xe, fd <= DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE && + args->preferred_mem_loc.region_instance != 0)) return false; - if (XE_IOCTL_DBG(xe, args->preferred_mem_loc.pad)) + if (XE_IOCTL_DBG(xe, args->preferred_mem_loc.migration_policy > + DRM_XE_MIGRATE_ONLY_SYSTEM_PAGES)) return false; if (XE_IOCTL_DBG(xe, args->preferred_mem_loc.reserved)) @@ -296,6 +317,41 @@ static bool madvise_args_are_sane(struct xe_device *xe, const struct drm_xe_madv return true; } +static int xe_madvise_details_init(struct xe_vm *vm, const struct drm_xe_madvise *args, + struct xe_madvise_details *details) +{ + struct xe_device *xe = vm->xe; + + memset(details, 0, sizeof(*details)); + + if (args->type == DRM_XE_MEM_RANGE_ATTR_PREFERRED_LOC) { + int fd = args->preferred_mem_loc.devmem_fd; + struct drm_pagemap *dpagemap; + + if (fd <= 0) + return 0; + + dpagemap = xe_drm_pagemap_from_fd(args->preferred_mem_loc.devmem_fd, + args->preferred_mem_loc.region_instance); + if (XE_IOCTL_DBG(xe, IS_ERR(dpagemap))) + return PTR_ERR(dpagemap); + + /* Don't allow a foreign placement without a fast interconnect! */ + if (XE_IOCTL_DBG(xe, dpagemap->pagemap->owner != vm->svm.peer.owner)) { + drm_pagemap_put(dpagemap); + return -ENOLINK; + } + details->dpagemap = dpagemap; + } + + return 0; +} + +static void xe_madvise_details_fini(struct xe_madvise_details *details) +{ + drm_pagemap_put(details->dpagemap); +} + static bool check_bo_args_are_sane(struct xe_vm *vm, struct xe_vma **vmas, int num_vmas, u32 atomic_val) { @@ -349,6 +405,7 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil struct drm_xe_madvise *args = data; struct xe_vmas_in_madvise_range madvise_range = {.addr = args->start, .range = args->range, }; + struct xe_madvise_details details; struct xe_vm *vm; struct drm_exec exec; int err, attr_type; @@ -373,13 +430,17 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil goto unlock_vm; } - err = xe_vm_alloc_madvise_vma(vm, args->start, args->range); + err = xe_madvise_details_init(vm, args, &details); if (err) goto unlock_vm; + err = xe_vm_alloc_madvise_vma(vm, args->start, args->range); + if (err) + goto madv_fini; + err = get_vmas(vm, &madvise_range); if (err || !madvise_range.num_vmas) - goto unlock_vm; + goto madv_fini; if (madvise_range.has_bo_vmas) { if (args->type == DRM_XE_MEM_RANGE_ATTR_ATOMIC) { @@ -387,7 +448,7 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil madvise_range.num_vmas, args->atomic.val)) { err = -EINVAL; - goto unlock_vm; + goto madv_fini; } } @@ -413,7 +474,8 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil } attr_type = array_index_nospec(args->type, ARRAY_SIZE(madvise_funcs)); - madvise_funcs[attr_type](xe, vm, madvise_range.vmas, madvise_range.num_vmas, args); + madvise_funcs[attr_type](xe, vm, madvise_range.vmas, madvise_range.num_vmas, args, + &details); err = xe_vm_invalidate_madvise_range(vm, args->start, args->start + args->range); @@ -425,6 +487,8 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil drm_exec_fini(&exec); kfree(madvise_range.vmas); madvise_range.vmas = NULL; +madv_fini: + xe_madvise_details_fini(&details); unlock_vm: up_write(&vm->lock); put_vm: diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h index 47853659a705..34c69bcea203 100644 --- a/include/uapi/drm/xe_drm.h +++ b/include/uapi/drm/xe_drm.h @@ -2071,7 +2071,13 @@ struct drm_xe_madvise { struct { #define DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE 0 #define DRM_XE_PREFERRED_LOC_DEFAULT_SYSTEM -1 - /** @preferred_mem_loc.devmem_fd: fd for preferred loc */ + /** + * @preferred_mem_loc.devmem_fd: + * Device file-descriptor of the device where the + * preferred memory is located, or one of the + * above special values. Please also see + * @preferred_mem_loc.region_instance below. + */ __u32 devmem_fd; #define DRM_XE_MIGRATE_ALL_PAGES 0 @@ -2079,8 +2085,14 @@ struct drm_xe_madvise { /** @preferred_mem_loc.migration_policy: Page migration policy */ __u16 migration_policy; - /** @preferred_mem_loc.pad : MBZ */ - __u16 pad; + /** + * @preferred_mem_loc.region_instance : Region instance. + * MBZ if @devmem_fd <= &DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE. + * Otherwise should point to the desired device + * VRAM instance of the device indicated by + * @preferred_mem_loc.devmem_fd. + */ + __u16 region_instance; /** @preferred_mem_loc.reserved : Reserved */ __u64 reserved; -- 2.51.1
