/* * Created: Fri Jan 8 09:01:26 1999 by faith@valinux.com * * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. * All Rights Reserved. * * Author Rickard E. (Rik) Faith * Author Gareth Hughes * * 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 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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. */ #include #include #include #include #include #include #include #include #include #include #include "drm_crtc_internal.h" #include "drm_internal.h" #include "drm_legacy.h" /** * DOC: getunique and setversion story * * BEWARE THE DRAGONS! MIND THE TRAPDOORS! * * In an attempt to warn anyone else who's trying to figure out what's going * on here, I'll try to summarize the story. First things first, let's clear up * the names, because the kernel internals, libdrm and the ioctls are all named * differently: * * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm * through the drmGetBusid function. * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All * that code is nerved in the kernel with drm_invalid_op(). * - The internal set_busid kernel functions and driver callbacks are * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is * nerved) allowed userspace to set the busid through the above ioctl. * - Other ioctls and functions involved are named consistently. * * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly * handling pci domains in the busid on ppc. Doing this correctly was only * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's * special with drm 1.2 and 1.3. * * Now the actual horror story of how device lookup in drm works. At large, * there's 2 different ways, either by busid, or by device driver name. * * Opening by busid is fairly simple: * * 1. First call SET_VERSION to make sure pci domains are handled properly. As a * side-effect this fills out the unique name in the master structure. * 2. Call GET_UNIQUE to read out the unique name from the master structure, * which matches the busid thanks to step 1. If it doesn't, proceed to try * the next device node. * * Opening by name is slightly different: * * 1. Directly call VERSION to get the version and to match against the driver * name returned by that ioctl. Note that SET_VERSION is not called, which * means the the unique name for the master node just opening is _not_ filled * out. This despite that with current drm device nodes are always bound to * one device, and can't be runtime assigned like with drm 1.0. * 2. Match driver name. If it mismatches, proceed to the next device node. * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by * checking that the first byte in the string is 0). If that's not the case * libdrm skips and proceeds to the next device node. Probably this is just * copypasta from drm 1.0 times where a set unique name meant that the driver * was in use already, but that's just conjecture. * * Long story short: To keep the open by name logic working, GET_UNIQUE must * _not_ return a unique string when SET_VERSION hasn't been called yet, * otherwise libdrm breaks. Even when that unique string can't ever change, and * is totally irrelevant for actually opening the device because runtime * assignable device instances were only support in drm 1.0, which is long dead. * But the libdrm code in drmOpenByName somehow survived, hence this can't be * broken. */ /* * Get the bus id. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_unique structure. * \return zero on success or a negative number on failure. * * Copies the bus id from drm_device::unique into user space. */ int drm_getunique(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_unique *u = data; struct drm_master *master; mutex_lock(&dev->master_mutex); master = file_priv->master; if (u->unique_len >= master->unique_len) { if (copy_to_user(u->unique, master->unique, master->unique_len)) { mutex_unlock(&dev->master_mutex); return -EFAULT; } } u->unique_len = master->unique_len; mutex_unlock(&dev->master_mutex); return 0; } static void drm_unset_busid(struct drm_device *dev, struct drm_master *master) { kfree(master->unique); master->unique = NULL; master->unique_len = 0; } static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) { struct drm_master *master = file_priv->master; int ret; if (master->unique != NULL) drm_unset_busid(dev, master); if (dev->dev && dev_is_pci(dev->dev)) { ret = drm_pci_set_busid(dev, master); if (ret) { drm_unset_busid(dev, master); return ret; } } else { WARN_ON(!dev->unique); master->unique = kstrdup(dev->unique, GFP_KERNEL); if (master->unique) master->unique_len = strlen(dev->unique); } return 0; } /* * Get client information. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_client structure. * * \return zero on success or a negative number on failure. * * Searches for the client with the specified index and copies its information * into userspace */ int drm_getclient(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_client *client = data; /* * Hollowed-out getclient ioctl to keep some dead old drm tests/tools * not breaking completely. Userspace tools stop enumerating one they * get -EINVAL, hence this is the return value we need to hand back for * no clients tracked. * * Unfortunately some clients (*cough* libva *cough*) use this in a fun * attempt to figure out whether they're authenticated or not. Since * that's the only thing they care about, give it to the directly * instead of walking one giant list. */ if (client->idx == 0) { client->auth = file_priv->authenticated; client->pid = task_pid_vnr(current); client->uid = overflowuid; client->magic = 0; client->iocs = 0; return 0; } else { return -EINVAL; } } /* * Get statistics information. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_stats structure. * * \return zero on success or a negative number on failure. */ static int drm_getstats(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_stats *stats = data; /* Clear stats to prevent userspace from eating its stack garbage. */ memset(stats, 0, sizeof(*stats)); return 0; } /* * Get device/driver capabilities */ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_get_cap *req = data; struct drm_crtc *crtc; req->value = 0; /* Only some caps make sense with UMS/render-only drivers. */ switch (req->capability) { case DRM_CAP_TIMESTAMP_MONOTONIC: req->value = 1; return 0; case DRM_CAP_PRIME: req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; return 0; case DRM_CAP_SYNCOBJ: req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ); return 0; case DRM_CAP_SYNCOBJ_TIMELINE: req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE); return 0; } /* Other caps only work with KMS drivers */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EOPNOTSUPP; switch (req->capability) { case DRM_CAP_DUMB_BUFFER: if (dev->driver->dumb_create) req->value = 1; break; case DRM_CAP_VBLANK_HIGH_CRTC: req->value = 1; break; case DRM_CAP_DUMB_PREFERRED_DEPTH: req->value = dev->mode_config.preferred_depth; break; case DRM_CAP_DUMB_PREFER_SHADOW: req->value = dev->mode_config.prefer_shadow; break; case DRM_CAP_ASYNC_PAGE_FLIP: req->value = dev->mode_config.async_page_flip; break; case DRM_CAP_PAGE_FLIP_TARGET: req->value = 1; drm_for_each_crtc(crtc, dev) { if (!crtc->funcs->page_flip_target) req->value = 0; } break; case DRM_CAP_CURSOR_WIDTH: if (dev->mode_config.cursor_width) req->value = dev->mode_config.cursor_width; else req->value = 64; break; case DRM_CAP_CURSOR_HEIGHT: if (dev->mode_config.cursor_height) req->value = dev->mode_config.cursor_height; else req->value = 64; break; case DRM_CAP_ADDFB2_MODIFIERS: req->value = dev->mode_config.allow_fb_modifiers; break; case DRM_CAP_CRTC_IN_VBLANK_EVENT: req->value = 1; break; default: return -EINVAL; } return 0; } /* * Set device/driver capabilities */ static int drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_set_client_cap *req = data; /* No render-only settable capabilities for now */ /* Below caps that only works with KMS drivers */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EOPNOTSUPP; switch (req->capability) { case DRM_CLIENT_CAP_STEREO_3D: if (req->value > 1) return -EINVAL; file_priv->stereo_allowed = req->value; break; case DRM_CLIENT_CAP_UNIVERSAL_PLANES: if (req->value > 1) return -EINVAL; file_priv->universal_planes = req->value; break; case DRM_CLIENT_CAP_ATOMIC: if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) return -EOPNOTSUPP; /* The modesetting DDX has a totally broken idea of atomic. */ if (current->comm[0] == 'X' && req->value == 1) { pr_info("broken atomic modeset userspace detected, disabling atomic\n"); return -EOPNOTSUPP; } if (req->value > 2) return -EINVAL; file_priv->atomic = req->value; file_priv->universal_planes = req->value; /* * No atomic user-space blows up on aspect ratio mode bits. */ file_priv->aspect_ratio_allowed = req->value; break; case DRM_CLIENT_CAP_ASPECT_RATIO: if (req->value > 1) return -EINVAL; file_priv->aspect_ratio_allowed = req->value; break; case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS: if (!file_priv->atomic) return -EINVAL; if (req->value > 1) return -EINVAL; file_priv->writeback_connectors = req->value; break; default: return -EINVAL; } return 0; } /* * Setversion ioctl. * * \param inode device inode. * \param file_priv DRM file private. * \param cmd command. * \param arg user argument, pointing to a drm_lock structure. * \return zero on success or negative number on failure. * * Sets the requested interface version */ static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_set_version *sv = data; int if_version, retcode = 0; mutex_lock(&dev->master_mutex); if (sv->drm_di_major != -1) { if (sv->drm_di_major != DRM_IF_MAJOR || sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { retcode = -EINVAL; goto done; } if_version = DRM_IF_VERSION(sv->drm_di_major, sv->drm_di_minor); dev->if_version = max(if_version, dev->if_version); if (sv->drm_di_minor >= 1) { /* * Version 1.1 includes tying of DRM to specific device * Version 1.4 has proper PCI domain support */ retcode = drm_set_busid(dev, file_priv); if (retcode) goto done; } } if (sv->drm_dd_major != -1) { if (sv->drm_dd_major != dev->driver->major || sv->drm_dd_minor < 0 || sv->drm_dd_minor > dev->driver->minor) { retcode = -EINVAL; goto done; } } done: sv->drm_di_major = DRM_IF_MAJOR; sv->drm_di_minor = DRM_IF_MINOR; sv->drm_dd_major = dev->driver->major; sv->drm_dd_minor = dev->driver->minor; mutex_unlock(&dev->master_mutex); return retcode; } /** * drm_noop - DRM no-op ioctl implementation * @dev: DRM device for the ioctl * @data: data pointer for the ioctl * @file_priv: DRM file for the ioctl call * * This no-op implementation for drm ioctls is useful for deprecated * functionality where we can't return a failure code because existing userspace * checks the result of the ioctl, but doesn't care about the action. * * Always returns successfully with 0. */ int drm_noop(struct drm_device *dev, void *data, struct drm_file *file_priv) { DRM_DEBUG("\n"); return 0; } EXPORT_SYMBOL(drm_noop); /** * drm_invalid_op - DRM invalid ioctl implementation * @dev: DRM device for the ioctl * @data: data pointer for the ioctl * @file_priv: DRM file for the ioctl call * * This no-op implementation for drm ioctls is useful for deprecated * functionality where we really don't want to allow userspace to call the ioctl * any more. This is the case for old ums interfaces for drivers that * transitioned to kms gradually and so kept the old legacy tables around. This * only applies to radeon and i915 kms drivers, other drivers shouldn't need to * use this function. * * Always fails with a return value of -EINVAL. */ int drm_invalid_op(struct drm_device *dev, void *data, struct drm_file *file_priv) { return -EINVAL; } EXPORT_SYMBOL(drm_invalid_op); /* * Copy and IOCTL return string to user space */ static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) { size_t len; /* don't attempt to copy a NULL pointer */ if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) { *buf_len = 0; return 0; } /* don't overflow userbuf */ len = strlen(value); if (len > *buf_len) len = *buf_len; /* let userspace know exact length of driver value (which could be * larger than the userspace-supplied buffer) */ *buf_len = strlen(value); /* finally, try filling in the userbuf */ if (len && buf) if (copy_to_user(buf, value, len)) return -EFAULT; return 0; } /* * Get version information * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument, pointing to a drm_version structure. * \return zero on success or negative number on failure. * * Fills in the version information in \p arg. */ int drm_version(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_version *version = data; int err; version->version_major = dev->driver->major; version->version_minor = dev->driver->minor; version->version_patchlevel = dev->driver->patchlevel; err = drm_copy_field(version->name, &version->name_len, dev->driver->name); if (!err) err = drm_copy_field(version->date, &version->date_len, dev->driver->date); if (!err) err = drm_copy_field(version->desc, &version->desc_len, dev->driver->desc); return err; } /** * drm_ioctl_permit - Check ioctl permissions against caller * * @flags: ioctl permission flags. * @file_priv: Pointer to struct drm_file identifying the caller. * * Checks whether the caller is allowed to run an ioctl with the * indicated permissions. * * Returns: * Zero if allowed, -EACCES otherwise. */ int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) { /* ROOT_ONLY is only for CAP_SYS_ADMIN */ if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) return -EACCES; /* AUTH is only for authenticated or render client */ if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && !file_priv->authenticated)) return -EACCES; /* MASTER is only for master or control clients */ if (unlikely((flags & DRM_MASTER) && !drm_is_current_master(file_priv))) return -EACCES; /* Render clients must be explicitly allowed */ if (unlikely(!(flags & DRM_RENDER_ALLOW) && drm_is_render_client(file_priv))) return -EACCES; return 0; } EXPORT_SYMBOL(drm_ioctl_permit); #define DRM_IOCTL_DEF(ioctl, _func, _flags) \ [DRM_IOCTL_NR(ioctl)] = { \ .cmd = ioctl, \ .func = _func, \ .flags = _flags, \ .name = #ioctl \ } #if IS_ENABLED(CONFIG_DRM_LEGACY) #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, _func, _flags) #else #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags) #endif /* Ioctl table */ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_legacy_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0), DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0), DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0), DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), #if IS_ENABLED(CONFIG_AGP) DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_legacy_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_legacy_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_legacy_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_legacy_agp_info_ioctl, DRM_AUTH), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_legacy_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_legacy_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_legacy_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_legacy_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), #endif DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH), DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0), DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER), }; #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) /** * DOC: driver specific ioctls * * First things first, driver private IOCTLs should only be needed for drivers * supporting rendering. Kernel modesetting is all standardized, and extended * through properties. There are a few exceptions in some existing drivers, * which define IOCTL for use by the display DRM master, but they all predate * properties. * * Now if you do have a render driver you always have to support it through * driver private properties. There's a few steps needed to wire all the things * up. * * First you need to define the structure for your IOCTL in your driver private * UAPI header in ``include/uapi/drm/my_driver_drm.h``:: * * struct my_driver_operation { * u32 some_thing; * u32 another_thing; * }; * * Please make sure that you follow all the best practices from * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl() * automatically zero-extends structures, hence make sure you can add more stuff * at the end, i.e. don't put a variable sized array there. * * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(), * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix:: * * ##define DRM_IOCTL_MY_DRIVER_OPERATION \ * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation) * * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire * up the handlers and set the access rights:: * * static const struct drm_ioctl_desc my_driver_ioctls[] = { * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation, * DRM_AUTH|DRM_RENDER_ALLOW), * }; * * And then assign this to the &drm_driver.ioctls field in your driver * structure. * * See the separate chapter on :ref:`file operations` for how * the driver-specific IOCTLs are wired up. */ long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata, u32 flags) { struct drm_file *file_priv = file->private_data; struct drm_device *dev = file_priv->minor->dev; int retcode; if (drm_dev_is_unplugged(dev)) return -ENODEV; retcode = drm_ioctl_permit(flags, file_priv); if (unlikely(retcode)) return retcode; /* Enforce sane locking for modern driver ioctls. */ if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) || (flags & DRM_UNLOCKED)) retcode = func(dev, kdata, file_priv); else { mutex_lock(&drm_global_mutex); retcode = func(dev, kdata, file_priv); mutex_unlock(&drm_global_mutex); } return retcode; } EXPORT_SYMBOL(drm_ioctl_kernel); /** * drm_ioctl - ioctl callback implementation for DRM drivers * @filp: file this ioctl is called on * @cmd: ioctl cmd number * @arg: user argument * * Looks up the ioctl function in the DRM core and the driver dispatch table, * stored in &drm_driver.ioctls. It checks for necessary permission by calling * drm_ioctl_permit(), and dispatches to the respective function. * * Returns: * Zero on success, negative error code on failure. */ long drm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct drm_file *file_priv = filp->private_data; struct drm_device *dev; const struct drm_ioctl_desc *ioctl = NULL; drm_ioctl_t *func; unsigned int nr = DRM_IOCTL_NR(cmd); int retcode = -EINVAL; char stack_kdata[128]; char *kdata = NULL; unsigned int in_size, out_size, drv_size, ksize; bool is_driver_ioctl; dev = file_priv->minor->dev; if (drm_dev_is_unplugged(dev)) return -ENODEV; if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE) return -ENOTTY; is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; if (is_driver_ioctl) { /* driver ioctl */ unsigned int index = nr - DRM_COMMAND_BASE; if (index >= dev->driver->num_ioctls) goto err_i1; index = array_index_nospec(index, dev->driver->num_ioctls); ioctl = &dev->driver->ioctls[index]; } else { /* core ioctl */ if (nr >= DRM_CORE_IOCTL_COUNT) goto err_i1; nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); ioctl = &drm_ioctls[nr]; } drv_size = _IOC_SIZE(ioctl->cmd); out_size = in_size = _IOC_SIZE(cmd); if ((cmd & ioctl->cmd & IOC_IN) == 0) in_size = 0; if ((cmd & ioctl->cmd & IOC_OUT) == 0) out_size = 0; ksize = max(max(in_size, out_size), drv_size); DRM_DEBUG("comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n", current->comm, task_pid_nr(current), (long)old_encode_dev(file_priv->minor->kdev->devt), file_priv->authenticated, ioctl->name); /* Do not trust userspace, use our own definition */ func = ioctl->func; if (unlikely(!func)) { DRM_DEBUG("no function\n"); retcode = -EINVAL; goto err_i1; } if (ksize <= sizeof(stack_kdata)) { kdata = stack_kdata; } else { kdata = kmalloc(ksize, GFP_KERNEL); if (!kdata) { retcode = -ENOMEM; goto err_i1; } } if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { retcode = -EFAULT; goto err_i1; } if (ksize > in_size) memset(kdata + in_size, 0, ksize - in_size); retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags); if (copy_to_user((void __user *)arg, kdata, out_size) != 0) retcode = -EFAULT; err_i1: if (!ioctl) DRM_DEBUG("invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", current->comm, task_pid_nr(current), (long)old_encode_dev(file_priv->minor->kdev->devt), file_priv->authenticated, cmd, nr); if (kdata != stack_kdata) kfree(kdata); if (retcode) DRM_DEBUG("comm=\"%s\", pid=%d, ret=%d\n", current->comm, task_pid_nr(current), retcode); return retcode; } EXPORT_SYMBOL(drm_ioctl); /** * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags * @nr: ioctl number * @flags: where to return the ioctl permission flags * * This ioctl is only used by the vmwgfx driver to augment the access checks * done by the drm core and insofar a pretty decent layering violation. This * shouldn't be used by any drivers. * * Returns: * True if the @nr corresponds to a DRM core ioctl number, false otherwise. */ bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) { if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) return false; if (nr >= DRM_CORE_IOCTL_COUNT) return false; nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); *flags = drm_ioctls[nr].flags; return true; } EXPORT_SYMBOL(drm_ioctl_flags);