diff options
Diffstat (limited to 'drivers/dma-buf')
| -rw-r--r-- | drivers/dma-buf/dma-buf-sysfs-stats.c | 2 | ||||
| -rw-r--r-- | drivers/dma-buf/dma-buf.c | 225 | ||||
| -rw-r--r-- | drivers/dma-buf/dma-heap.c | 2 | ||||
| -rw-r--r-- | drivers/dma-buf/dma-resv.c | 9 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/cma_heap.c | 3 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/system_heap.c | 3 | ||||
| -rw-r--r-- | drivers/dma-buf/st-dma-fence-chain.c | 6 | ||||
| -rw-r--r-- | drivers/dma-buf/udmabuf.c | 3 |
8 files changed, 213 insertions, 40 deletions
diff --git a/drivers/dma-buf/dma-buf-sysfs-stats.c b/drivers/dma-buf/dma-buf-sysfs-stats.c index 4b680e10c15a..fbf725fae7c1 100644 --- a/drivers/dma-buf/dma-buf-sysfs-stats.c +++ b/drivers/dma-buf/dma-buf-sysfs-stats.c @@ -132,7 +132,7 @@ void dma_buf_stats_teardown(struct dma_buf *dmabuf) /* Statistics files do not need to send uevents. */ -static int dmabuf_sysfs_uevent_filter(struct kobject *kobj) +static int dmabuf_sysfs_uevent_filter(const struct kobject *kobj) { return 0; } diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index eb6b59363c4f..e6528767efc7 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -131,6 +131,7 @@ static struct file_system_type dma_buf_fs_type = { static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma) { struct dma_buf *dmabuf; + int ret; if (!is_dma_buf_file(file)) return -EINVAL; @@ -146,7 +147,11 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma) dmabuf->size >> PAGE_SHIFT) return -EINVAL; - return dmabuf->ops->mmap(dmabuf, vma); + dma_resv_lock(dmabuf->resv, NULL); + ret = dmabuf->ops->mmap(dmabuf, vma); + dma_resv_unlock(dmabuf->resv); + + return ret; } static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence) @@ -655,7 +660,6 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) init_waitqueue_head(&dmabuf->poll); dmabuf->cb_in.poll = dmabuf->cb_out.poll = &dmabuf->poll; dmabuf->cb_in.active = dmabuf->cb_out.active = 0; - mutex_init(&dmabuf->lock); INIT_LIST_HEAD(&dmabuf->attachments); if (!resv) { @@ -801,6 +805,70 @@ static struct sg_table * __map_dma_buf(struct dma_buf_attachment *attach, } /** + * DOC: locking convention + * + * In order to avoid deadlock situations between dma-buf exports and importers, + * all dma-buf API users must follow the common dma-buf locking convention. + * + * Convention for importers + * + * 1. Importers must hold the dma-buf reservation lock when calling these + * functions: + * + * - dma_buf_pin() + * - dma_buf_unpin() + * - dma_buf_map_attachment() + * - dma_buf_unmap_attachment() + * - dma_buf_vmap() + * - dma_buf_vunmap() + * + * 2. Importers must not hold the dma-buf reservation lock when calling these + * functions: + * + * - dma_buf_attach() + * - dma_buf_dynamic_attach() + * - dma_buf_detach() + * - dma_buf_export( + * - dma_buf_fd() + * - dma_buf_get() + * - dma_buf_put() + * - dma_buf_mmap() + * - dma_buf_begin_cpu_access() + * - dma_buf_end_cpu_access() + * - dma_buf_map_attachment_unlocked() + * - dma_buf_unmap_attachment_unlocked() + * - dma_buf_vmap_unlocked() + * - dma_buf_vunmap_unlocked() + * + * Convention for exporters + * + * 1. These &dma_buf_ops callbacks are invoked with unlocked dma-buf + * reservation and exporter can take the lock: + * + * - &dma_buf_ops.attach() + * - &dma_buf_ops.detach() + * - &dma_buf_ops.release() + * - &dma_buf_ops.begin_cpu_access() + * - &dma_buf_ops.end_cpu_access() + * + * 2. These &dma_buf_ops callbacks are invoked with locked dma-buf + * reservation and exporter can't take the lock: + * + * - &dma_buf_ops.pin() + * - &dma_buf_ops.unpin() + * - &dma_buf_ops.map_dma_buf() + * - &dma_buf_ops.unmap_dma_buf() + * - &dma_buf_ops.mmap() + * - &dma_buf_ops.vmap() + * - &dma_buf_ops.vunmap() + * + * 3. Exporters must hold the dma-buf reservation lock when calling these + * functions: + * + * - dma_buf_move_notify() + */ + +/** * dma_buf_dynamic_attach - Add the device to dma_buf's attachments list * @dmabuf: [in] buffer to attach device to. * @dev: [in] device to be attached. @@ -864,8 +932,8 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, dma_buf_is_dynamic(dmabuf)) { struct sg_table *sgt; + dma_resv_lock(attach->dmabuf->resv, NULL); if (dma_buf_is_dynamic(attach->dmabuf)) { - dma_resv_lock(attach->dmabuf->resv, NULL); ret = dmabuf->ops->pin(attach); if (ret) goto err_unlock; @@ -878,8 +946,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, ret = PTR_ERR(sgt); goto err_unpin; } - if (dma_buf_is_dynamic(attach->dmabuf)) - dma_resv_unlock(attach->dmabuf->resv); + dma_resv_unlock(attach->dmabuf->resv); attach->sgt = sgt; attach->dir = DMA_BIDIRECTIONAL; } @@ -895,8 +962,7 @@ err_unpin: dmabuf->ops->unpin(attach); err_unlock: - if (dma_buf_is_dynamic(attach->dmabuf)) - dma_resv_unlock(attach->dmabuf->resv); + dma_resv_unlock(attach->dmabuf->resv); dma_buf_detach(dmabuf, attach); return ERR_PTR(ret); @@ -939,24 +1005,22 @@ static void __unmap_dma_buf(struct dma_buf_attachment *attach, */ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) { - if (WARN_ON(!dmabuf || !attach)) + if (WARN_ON(!dmabuf || !attach || dmabuf != attach->dmabuf)) return; + dma_resv_lock(dmabuf->resv, NULL); + if (attach->sgt) { - if (dma_buf_is_dynamic(attach->dmabuf)) - dma_resv_lock(attach->dmabuf->resv, NULL); __unmap_dma_buf(attach, attach->sgt, attach->dir); - if (dma_buf_is_dynamic(attach->dmabuf)) { + if (dma_buf_is_dynamic(attach->dmabuf)) dmabuf->ops->unpin(attach); - dma_resv_unlock(attach->dmabuf->resv); - } } - - dma_resv_lock(dmabuf->resv, NULL); list_del(&attach->node); + dma_resv_unlock(dmabuf->resv); + if (dmabuf->ops->detach) dmabuf->ops->detach(dmabuf, attach); @@ -1047,8 +1111,7 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, if (WARN_ON(!attach || !attach->dmabuf)) return ERR_PTR(-EINVAL); - if (dma_buf_attachment_is_dynamic(attach)) - dma_resv_assert_held(attach->dmabuf->resv); + dma_resv_assert_held(attach->dmabuf->resv); if (attach->sgt) { /* @@ -1063,7 +1126,6 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, } if (dma_buf_is_dynamic(attach->dmabuf)) { - dma_resv_assert_held(attach->dmabuf->resv); if (!IS_ENABLED(CONFIG_DMABUF_MOVE_NOTIFY)) { r = attach->dmabuf->ops->pin(attach); if (r) @@ -1106,6 +1168,34 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment, DMA_BUF); /** + * dma_buf_map_attachment_unlocked - Returns the scatterlist table of the attachment; + * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the + * dma_buf_ops. + * @attach: [in] attachment whose scatterlist is to be returned + * @direction: [in] direction of DMA transfer + * + * Unlocked variant of dma_buf_map_attachment(). + */ +struct sg_table * +dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach, + enum dma_data_direction direction) +{ + struct sg_table *sg_table; + + might_sleep(); + + if (WARN_ON(!attach || !attach->dmabuf)) + return ERR_PTR(-EINVAL); + + dma_resv_lock(attach->dmabuf->resv, NULL); + sg_table = dma_buf_map_attachment(attach, direction); + dma_resv_unlock(attach->dmabuf->resv); + + return sg_table; +} +EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment_unlocked, DMA_BUF); + +/** * dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of * dma_buf_ops. @@ -1124,15 +1214,11 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, if (WARN_ON(!attach || !attach->dmabuf || !sg_table)) return; - if (dma_buf_attachment_is_dynamic(attach)) - dma_resv_assert_held(attach->dmabuf->resv); + dma_resv_assert_held(attach->dmabuf->resv); if (attach->sgt == sg_table) return; - if (dma_buf_is_dynamic(attach->dmabuf)) - dma_resv_assert_held(attach->dmabuf->resv); - __unmap_dma_buf(attach, sg_table, direction); if (dma_buf_is_dynamic(attach->dmabuf) && @@ -1142,6 +1228,31 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment, DMA_BUF); /** + * dma_buf_unmap_attachment_unlocked - unmaps and decreases usecount of the buffer;might + * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of + * dma_buf_ops. + * @attach: [in] attachment to unmap buffer from + * @sg_table: [in] scatterlist info of the buffer to unmap + * @direction: [in] direction of DMA transfer + * + * Unlocked variant of dma_buf_unmap_attachment(). + */ +void dma_buf_unmap_attachment_unlocked(struct dma_buf_attachment *attach, + struct sg_table *sg_table, + enum dma_data_direction direction) +{ + might_sleep(); + + if (WARN_ON(!attach || !attach->dmabuf || !sg_table)) + return; + + dma_resv_lock(attach->dmabuf->resv, NULL); + dma_buf_unmap_attachment(attach, sg_table, direction); + dma_resv_unlock(attach->dmabuf->resv); +} +EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment_unlocked, DMA_BUF); + +/** * dma_buf_move_notify - notify attachments that DMA-buf is moving * * @dmabuf: [in] buffer which is moving @@ -1352,6 +1463,8 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_end_cpu_access, DMA_BUF); int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, unsigned long pgoff) { + int ret; + if (WARN_ON(!dmabuf || !vma)) return -EINVAL; @@ -1372,7 +1485,11 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, vma_set_file(vma, dmabuf->file); vma->vm_pgoff = pgoff; - return dmabuf->ops->mmap(dmabuf, vma); + dma_resv_lock(dmabuf->resv, NULL); + ret = dmabuf->ops->mmap(dmabuf, vma); + dma_resv_unlock(dmabuf->resv); + + return ret; } EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF); @@ -1395,42 +1512,68 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF); int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map) { struct iosys_map ptr; - int ret = 0; + int ret; iosys_map_clear(map); if (WARN_ON(!dmabuf)) return -EINVAL; + dma_resv_assert_held(dmabuf->resv); + if (!dmabuf->ops->vmap) return -EINVAL; - mutex_lock(&dmabuf->lock); if (dmabuf->vmapping_counter) { dmabuf->vmapping_counter++; BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr)); *map = dmabuf->vmap_ptr; - goto out_unlock; + return 0; } BUG_ON(iosys_map_is_set(&dmabuf->vmap_ptr)); ret = dmabuf->ops->vmap(dmabuf, &ptr); if (WARN_ON_ONCE(ret)) - goto out_unlock; + return ret; dmabuf->vmap_ptr = ptr; dmabuf->vmapping_counter = 1; *map = dmabuf->vmap_ptr; -out_unlock: - mutex_unlock(&dmabuf->lock); - return ret; + return 0; } EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF); /** + * dma_buf_vmap_unlocked - Create virtual mapping for the buffer object into kernel + * address space. Same restrictions as for vmap and friends apply. + * @dmabuf: [in] buffer to vmap + * @map: [out] returns the vmap pointer + * + * Unlocked version of dma_buf_vmap() + * + * Returns 0 on success, or a negative errno code otherwise. + */ +int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map) +{ + int ret; + + iosys_map_clear(map); + + if (WARN_ON(!dmabuf)) + return -EINVAL; + + dma_resv_lock(dmabuf->resv, NULL); + ret = dma_buf_vmap(dmabuf, map); + dma_resv_unlock(dmabuf->resv); + + return ret; +} +EXPORT_SYMBOL_NS_GPL(dma_buf_vmap_unlocked, DMA_BUF); + +/** * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap. * @dmabuf: [in] buffer to vunmap * @map: [in] vmap pointer to vunmap @@ -1440,20 +1583,36 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) if (WARN_ON(!dmabuf)) return; + dma_resv_assert_held(dmabuf->resv); + BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr)); BUG_ON(dmabuf->vmapping_counter == 0); BUG_ON(!iosys_map_is_equal(&dmabuf->vmap_ptr, map)); - mutex_lock(&dmabuf->lock); if (--dmabuf->vmapping_counter == 0) { if (dmabuf->ops->vunmap) dmabuf->ops->vunmap(dmabuf, map); iosys_map_clear(&dmabuf->vmap_ptr); } - mutex_unlock(&dmabuf->lock); } EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF); +/** + * dma_buf_vunmap_unlocked - Unmap a vmap obtained by dma_buf_vmap. + * @dmabuf: [in] buffer to vunmap + * @map: [in] vmap pointer to vunmap + */ +void dma_buf_vunmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map) +{ + if (WARN_ON(!dmabuf)) + return; + + dma_resv_lock(dmabuf->resv, NULL); + dma_buf_vunmap(dmabuf, map); + dma_resv_unlock(dmabuf->resv); +} +EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap_unlocked, DMA_BUF); + #ifdef CONFIG_DEBUG_FS static int dma_buf_debug_show(struct seq_file *s, void *unused) { diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c index 59d158873f4c..c9e41e8a9e27 100644 --- a/drivers/dma-buf/dma-heap.c +++ b/drivers/dma-buf/dma-heap.c @@ -301,7 +301,7 @@ err0: return err_ret; } -static char *dma_heap_devnode(struct device *dev, umode_t *mode) +static char *dma_heap_devnode(const struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "dma_heap/%s", dev_name(dev)); } diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index e3885c90a3ac..1c76aed8e262 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -98,12 +98,17 @@ static void dma_resv_list_set(struct dma_resv_list *list, static struct dma_resv_list *dma_resv_list_alloc(unsigned int max_fences) { struct dma_resv_list *list; + size_t size; - list = kmalloc(struct_size(list, table, max_fences), GFP_KERNEL); + /* Round up to the next kmalloc bucket size. */ + size = kmalloc_size_roundup(struct_size(list, table, max_fences)); + + list = kmalloc(size, GFP_KERNEL); if (!list) return NULL; - list->max_fences = (ksize(list) - offsetof(typeof(*list), table)) / + /* Given the resulting bucket size, recalculated max_fences. */ + list->max_fences = (size - offsetof(typeof(*list), table)) / sizeof(*list->table); return list; diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c index 28fb04eccdd0..1131fb943992 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -13,6 +13,7 @@ #include <linux/dma-buf.h> #include <linux/dma-heap.h> #include <linux/dma-map-ops.h> +#include <linux/dma-resv.h> #include <linux/err.h> #include <linux/highmem.h> #include <linux/io.h> @@ -182,6 +183,8 @@ static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) { struct cma_heap_buffer *buffer = dmabuf->priv; + dma_resv_assert_held(dmabuf->resv); + if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0) return -EINVAL; diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index fcf836ba9c1f..e8bd10e60998 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -13,6 +13,7 @@ #include <linux/dma-buf.h> #include <linux/dma-mapping.h> #include <linux/dma-heap.h> +#include <linux/dma-resv.h> #include <linux/err.h> #include <linux/highmem.h> #include <linux/mm.h> @@ -201,6 +202,8 @@ static int system_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) struct sg_page_iter piter; int ret; + dma_resv_assert_held(dmabuf->resv); + for_each_sgtable_page(table, &piter, vma->vm_pgoff) { struct page *page = sg_page_iter_page(&piter); diff --git a/drivers/dma-buf/st-dma-fence-chain.c b/drivers/dma-buf/st-dma-fence-chain.c index 0a9b099d0518..c0979c8049b5 100644 --- a/drivers/dma-buf/st-dma-fence-chain.c +++ b/drivers/dma-buf/st-dma-fence-chain.c @@ -400,7 +400,7 @@ static int __find_race(void *arg) struct dma_fence *fence = dma_fence_get(data->fc.tail); int seqno; - seqno = prandom_u32_max(data->fc.chain_length) + 1; + seqno = get_random_u32_inclusive(1, data->fc.chain_length); err = dma_fence_chain_find_seqno(&fence, seqno); if (err) { @@ -429,7 +429,7 @@ static int __find_race(void *arg) dma_fence_put(fence); signal: - seqno = prandom_u32_max(data->fc.chain_length - 1); + seqno = get_random_u32_below(data->fc.chain_length - 1); dma_fence_signal(data->fc.fences[seqno]); cond_resched(); } @@ -637,7 +637,7 @@ static void randomise_fences(struct fence_chains *fc) while (--count) { unsigned int swp; - swp = prandom_u32_max(count + 1); + swp = get_random_u32_below(count + 1); if (swp == count) continue; diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 2bcdb935a3ac..283816fbd72f 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -2,6 +2,7 @@ #include <linux/cred.h> #include <linux/device.h> #include <linux/dma-buf.h> +#include <linux/dma-resv.h> #include <linux/highmem.h> #include <linux/init.h> #include <linux/kernel.h> @@ -49,6 +50,8 @@ static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma) { struct udmabuf *ubuf = buf->priv; + dma_resv_assert_held(buf->resv); + if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0) return -EINVAL; |