diff options
Diffstat (limited to 'drivers/gpu/drm/drm_file.c')
| -rw-r--r-- | drivers/gpu/drm/drm_file.c | 231 |
1 files changed, 224 insertions, 7 deletions
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c index 92d16724f949..eb009d3ab48f 100644 --- a/drivers/gpu/drm/drm_file.c +++ b/drivers/gpu/drm/drm_file.c @@ -48,9 +48,45 @@ #include "drm_internal.h" #include "drm_legacy.h" +#if defined(CONFIG_MMU) && defined(CONFIG_TRANSPARENT_HUGEPAGE) +#include <uapi/asm/mman.h> +#include <drm/drm_vma_manager.h> +#endif + /* from BKL pushdown */ DEFINE_MUTEX(drm_global_mutex); +bool drm_dev_needs_global_mutex(struct drm_device *dev) +{ + /* + * Legacy drivers rely on all kinds of BKL locking semantics, don't + * bother. They also still need BKL locking for their ioctls, so better + * safe than sorry. + */ + if (drm_core_check_feature(dev, DRIVER_LEGACY)) + return true; + + /* + * The deprecated ->load callback must be called after the driver is + * already registered. This means such drivers rely on the BKL to make + * sure an open can't proceed until the driver is actually fully set up. + * Similar hilarity holds for the unload callback. + */ + if (dev->driver->load || dev->driver->unload) + return true; + + /* + * Drivers with the lastclose callback assume that it's synchronized + * against concurrent opens, which again needs the BKL. The proper fix + * is to use the drm_client infrastructure with proper locking for each + * client. + */ + if (dev->driver->lastclose) + return true; + + return false; +} + /** * DOC: file operations * @@ -220,7 +256,7 @@ void drm_file_free(struct drm_file *file) DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", task_pid_nr(current), (long)old_encode_dev(file->minor->kdev->devt), - dev->open_count); + atomic_read(&dev->open_count)); if (drm_core_check_feature(dev, DRIVER_LEGACY) && dev->driver->preclose) @@ -379,7 +415,10 @@ int drm_open(struct inode *inode, struct file *filp) return PTR_ERR(minor); dev = minor->dev; - if (!dev->open_count++) + if (drm_dev_needs_global_mutex(dev)) + mutex_lock(&drm_global_mutex); + + if (!atomic_fetch_inc(&dev->open_count)) need_setup = 1; /* share address_space across all char-devs of a single device */ @@ -395,10 +434,16 @@ int drm_open(struct inode *inode, struct file *filp) goto err_undo; } } + + if (drm_dev_needs_global_mutex(dev)) + mutex_unlock(&drm_global_mutex); + return 0; err_undo: - dev->open_count--; + atomic_dec(&dev->open_count); + if (drm_dev_needs_global_mutex(dev)) + mutex_unlock(&drm_global_mutex); drm_minor_release(minor); return retcode; } @@ -438,16 +483,18 @@ int drm_release(struct inode *inode, struct file *filp) struct drm_minor *minor = file_priv->minor; struct drm_device *dev = minor->dev; - mutex_lock(&drm_global_mutex); + if (drm_dev_needs_global_mutex(dev)) + mutex_lock(&drm_global_mutex); - DRM_DEBUG("open_count = %d\n", dev->open_count); + DRM_DEBUG("open_count = %d\n", atomic_read(&dev->open_count)); drm_close_helper(filp); - if (!--dev->open_count) + if (atomic_dec_and_test(&dev->open_count)) drm_lastclose(dev); - mutex_unlock(&drm_global_mutex); + if (drm_dev_needs_global_mutex(dev)) + mutex_unlock(&drm_global_mutex); drm_minor_release(minor); @@ -456,6 +503,40 @@ int drm_release(struct inode *inode, struct file *filp) EXPORT_SYMBOL(drm_release); /** + * drm_release_noglobal - release method for DRM file + * @inode: device inode + * @filp: file pointer. + * + * This function may be used by drivers as their &file_operations.release + * method. It frees any resources associated with the open file prior to taking + * the drm_global_mutex, which then calls the &drm_driver.postclose driver + * callback. If this is the last open file for the DRM device also proceeds to + * call the &drm_driver.lastclose driver callback. + * + * RETURNS: + * + * Always succeeds and returns 0. + */ +int drm_release_noglobal(struct inode *inode, struct file *filp) +{ + struct drm_file *file_priv = filp->private_data; + struct drm_minor *minor = file_priv->minor; + struct drm_device *dev = minor->dev; + + drm_close_helper(filp); + + if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) { + drm_lastclose(dev); + mutex_unlock(&drm_global_mutex); + } + + drm_minor_release(minor); + + return 0; +} +EXPORT_SYMBOL(drm_release_noglobal); + +/** * drm_read - read method for DRM file * @filp: file pointer * @buffer: userspace destination pointer for the read @@ -796,3 +877,139 @@ struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags) return file; } EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile); + +#ifdef CONFIG_MMU +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +/* + * drm_addr_inflate() attempts to construct an aligned area by inflating + * the area size and skipping the unaligned start of the area. + * adapted from shmem_get_unmapped_area() + */ +static unsigned long drm_addr_inflate(unsigned long addr, + unsigned long len, + unsigned long pgoff, + unsigned long flags, + unsigned long huge_size) +{ + unsigned long offset, inflated_len; + unsigned long inflated_addr; + unsigned long inflated_offset; + + offset = (pgoff << PAGE_SHIFT) & (huge_size - 1); + if (offset && offset + len < 2 * huge_size) + return addr; + if ((addr & (huge_size - 1)) == offset) + return addr; + + inflated_len = len + huge_size - PAGE_SIZE; + if (inflated_len > TASK_SIZE) + return addr; + if (inflated_len < len) + return addr; + + inflated_addr = current->mm->get_unmapped_area(NULL, 0, inflated_len, + 0, flags); + if (IS_ERR_VALUE(inflated_addr)) + return addr; + if (inflated_addr & ~PAGE_MASK) + return addr; + + inflated_offset = inflated_addr & (huge_size - 1); + inflated_addr += offset - inflated_offset; + if (inflated_offset > offset) + inflated_addr += huge_size; + + if (inflated_addr > TASK_SIZE - len) + return addr; + + return inflated_addr; +} + +/** + * drm_get_unmapped_area() - Get an unused user-space virtual memory area + * suitable for huge page table entries. + * @file: The struct file representing the address space being mmap()'d. + * @uaddr: Start address suggested by user-space. + * @len: Length of the area. + * @pgoff: The page offset into the address space. + * @flags: mmap flags + * @mgr: The address space manager used by the drm driver. This argument can + * probably be removed at some point when all drivers use the same + * address space manager. + * + * This function attempts to find an unused user-space virtual memory area + * that can accommodate the size we want to map, and that is properly + * aligned to facilitate huge page table entries matching actual + * huge pages or huge page aligned memory in buffer objects. Buffer objects + * are assumed to start at huge page boundary pfns (io memory) or be + * populated by huge pages aligned to the start of the buffer object + * (system- or coherent memory). Adapted from shmem_get_unmapped_area. + * + * Return: aligned user-space address. + */ +unsigned long drm_get_unmapped_area(struct file *file, + unsigned long uaddr, unsigned long len, + unsigned long pgoff, unsigned long flags, + struct drm_vma_offset_manager *mgr) +{ + unsigned long addr; + unsigned long inflated_addr; + struct drm_vma_offset_node *node; + + if (len > TASK_SIZE) + return -ENOMEM; + + /* + * @pgoff is the file page-offset the huge page boundaries of + * which typically aligns to physical address huge page boundaries. + * That's not true for DRM, however, where physical address huge + * page boundaries instead are aligned with the offset from + * buffer object start. So adjust @pgoff to be the offset from + * buffer object start. + */ + drm_vma_offset_lock_lookup(mgr); + node = drm_vma_offset_lookup_locked(mgr, pgoff, 1); + if (node) + pgoff -= node->vm_node.start; + drm_vma_offset_unlock_lookup(mgr); + + addr = current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags); + if (IS_ERR_VALUE(addr)) + return addr; + if (addr & ~PAGE_MASK) + return addr; + if (addr > TASK_SIZE - len) + return addr; + + if (len < HPAGE_PMD_SIZE) + return addr; + if (flags & MAP_FIXED) + return addr; + /* + * Our priority is to support MAP_SHARED mapped hugely; + * and support MAP_PRIVATE mapped hugely too, until it is COWed. + * But if caller specified an address hint, respect that as before. + */ + if (uaddr) + return addr; + + inflated_addr = drm_addr_inflate(addr, len, pgoff, flags, + HPAGE_PMD_SIZE); + + if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) && + len >= HPAGE_PUD_SIZE) + inflated_addr = drm_addr_inflate(inflated_addr, len, pgoff, + flags, HPAGE_PUD_SIZE); + return inflated_addr; +} +#else /* CONFIG_TRANSPARENT_HUGEPAGE */ +unsigned long drm_get_unmapped_area(struct file *file, + unsigned long uaddr, unsigned long len, + unsigned long pgoff, unsigned long flags, + struct drm_vma_offset_manager *mgr) +{ + return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags); +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +EXPORT_SYMBOL_GPL(drm_get_unmapped_area); +#endif /* CONFIG_MMU */ |