summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/msm/msm_gem.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/gpu/drm/msm/msm_gem.c
Initial import
Diffstat (limited to 'drivers/gpu/drm/msm/msm_gem.c')
-rw-r--r--drivers/gpu/drm/msm/msm_gem.c707
1 files changed, 707 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
new file mode 100644
index 000000000..52839769e
--- /dev/null
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -0,0 +1,707 @@
+/*
+ * Copyright (C) 2013 Red Hat
+ * Author: Rob Clark <robdclark@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/shmem_fs.h>
+#include <linux/dma-buf.h>
+
+#include "msm_drv.h"
+#include "msm_gem.h"
+#include "msm_gpu.h"
+#include "msm_mmu.h"
+
+static dma_addr_t physaddr(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ struct msm_drm_private *priv = obj->dev->dev_private;
+ return (((dma_addr_t)msm_obj->vram_node->start) << PAGE_SHIFT) +
+ priv->vram.paddr;
+}
+
+static bool use_pages(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ return !msm_obj->vram_node;
+}
+
+/* allocate pages from VRAM carveout, used when no IOMMU: */
+static struct page **get_pages_vram(struct drm_gem_object *obj,
+ int npages)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ struct msm_drm_private *priv = obj->dev->dev_private;
+ dma_addr_t paddr;
+ struct page **p;
+ int ret, i;
+
+ p = drm_malloc_ab(npages, sizeof(struct page *));
+ if (!p)
+ return ERR_PTR(-ENOMEM);
+
+ ret = drm_mm_insert_node(&priv->vram.mm, msm_obj->vram_node,
+ npages, 0, DRM_MM_SEARCH_DEFAULT);
+ if (ret) {
+ drm_free_large(p);
+ return ERR_PTR(ret);
+ }
+
+ paddr = physaddr(obj);
+ for (i = 0; i < npages; i++) {
+ p[i] = phys_to_page(paddr);
+ paddr += PAGE_SIZE;
+ }
+
+ return p;
+}
+
+/* called with dev->struct_mutex held */
+static struct page **get_pages(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ if (!msm_obj->pages) {
+ struct drm_device *dev = obj->dev;
+ struct page **p;
+ int npages = obj->size >> PAGE_SHIFT;
+
+ if (use_pages(obj))
+ p = drm_gem_get_pages(obj);
+ else
+ p = get_pages_vram(obj, npages);
+
+ if (IS_ERR(p)) {
+ dev_err(dev->dev, "could not get pages: %ld\n",
+ PTR_ERR(p));
+ return p;
+ }
+
+ msm_obj->sgt = drm_prime_pages_to_sg(p, npages);
+ if (IS_ERR(msm_obj->sgt)) {
+ dev_err(dev->dev, "failed to allocate sgt\n");
+ return ERR_CAST(msm_obj->sgt);
+ }
+
+ msm_obj->pages = p;
+
+ /* For non-cached buffers, ensure the new pages are clean
+ * because display controller, GPU, etc. are not coherent:
+ */
+ if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED))
+ dma_map_sg(dev->dev, msm_obj->sgt->sgl,
+ msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ }
+
+ return msm_obj->pages;
+}
+
+static void put_pages(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ if (msm_obj->pages) {
+ /* For non-cached buffers, ensure the new pages are clean
+ * because display controller, GPU, etc. are not coherent:
+ */
+ if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED))
+ dma_unmap_sg(obj->dev->dev, msm_obj->sgt->sgl,
+ msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ sg_free_table(msm_obj->sgt);
+ kfree(msm_obj->sgt);
+
+ if (use_pages(obj))
+ drm_gem_put_pages(obj, msm_obj->pages, true, false);
+ else {
+ drm_mm_remove_node(msm_obj->vram_node);
+ drm_free_large(msm_obj->pages);
+ }
+
+ msm_obj->pages = NULL;
+ }
+}
+
+struct page **msm_gem_get_pages(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj->dev;
+ struct page **p;
+ mutex_lock(&dev->struct_mutex);
+ p = get_pages(obj);
+ mutex_unlock(&dev->struct_mutex);
+ return p;
+}
+
+void msm_gem_put_pages(struct drm_gem_object *obj)
+{
+ /* when we start tracking the pin count, then do something here */
+}
+
+int msm_gem_mmap_obj(struct drm_gem_object *obj,
+ struct vm_area_struct *vma)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ vma->vm_flags &= ~VM_PFNMAP;
+ vma->vm_flags |= VM_MIXEDMAP;
+
+ if (msm_obj->flags & MSM_BO_WC) {
+ vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
+ } else if (msm_obj->flags & MSM_BO_UNCACHED) {
+ vma->vm_page_prot = pgprot_noncached(vm_get_page_prot(vma->vm_flags));
+ } else {
+ /*
+ * Shunt off cached objs to shmem file so they have their own
+ * address_space (so unmap_mapping_range does what we want,
+ * in particular in the case of mmap'd dmabufs)
+ */
+ fput(vma->vm_file);
+ get_file(obj->filp);
+ vma->vm_pgoff = 0;
+ vma->vm_file = obj->filp;
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ }
+
+ return 0;
+}
+
+int msm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ int ret;
+
+ ret = drm_gem_mmap(filp, vma);
+ if (ret) {
+ DBG("mmap failed: %d", ret);
+ return ret;
+ }
+
+ return msm_gem_mmap_obj(vma->vm_private_data, vma);
+}
+
+int msm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct drm_gem_object *obj = vma->vm_private_data;
+ struct drm_device *dev = obj->dev;
+ struct page **pages;
+ unsigned long pfn;
+ pgoff_t pgoff;
+ int ret;
+
+ /* Make sure we don't parallel update on a fault, nor move or remove
+ * something from beneath our feet
+ */
+ ret = mutex_lock_interruptible(&dev->struct_mutex);
+ if (ret)
+ goto out;
+
+ /* make sure we have pages attached now */
+ pages = get_pages(obj);
+ if (IS_ERR(pages)) {
+ ret = PTR_ERR(pages);
+ goto out_unlock;
+ }
+
+ /* We don't use vmf->pgoff since that has the fake offset: */
+ pgoff = ((unsigned long)vmf->virtual_address -
+ vma->vm_start) >> PAGE_SHIFT;
+
+ pfn = page_to_pfn(pages[pgoff]);
+
+ VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
+ pfn, pfn << PAGE_SHIFT);
+
+ ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
+
+out_unlock:
+ mutex_unlock(&dev->struct_mutex);
+out:
+ switch (ret) {
+ case -EAGAIN:
+ case 0:
+ case -ERESTARTSYS:
+ case -EINTR:
+ case -EBUSY:
+ /*
+ * EBUSY is ok: this just means that another thread
+ * already did the job.
+ */
+ return VM_FAULT_NOPAGE;
+ case -ENOMEM:
+ return VM_FAULT_OOM;
+ default:
+ return VM_FAULT_SIGBUS;
+ }
+}
+
+/** get mmap offset */
+static uint64_t mmap_offset(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj->dev;
+ int ret;
+
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+ /* Make it mmapable */
+ ret = drm_gem_create_mmap_offset(obj);
+
+ if (ret) {
+ dev_err(dev->dev, "could not allocate mmap offset\n");
+ return 0;
+ }
+
+ return drm_vma_node_offset_addr(&obj->vma_node);
+}
+
+uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj)
+{
+ uint64_t offset;
+ mutex_lock(&obj->dev->struct_mutex);
+ offset = mmap_offset(obj);
+ mutex_unlock(&obj->dev->struct_mutex);
+ return offset;
+}
+
+/* should be called under struct_mutex.. although it can be called
+ * from atomic context without struct_mutex to acquire an extra
+ * iova ref if you know one is already held.
+ *
+ * That means when I do eventually need to add support for unpinning
+ * the refcnt counter needs to be atomic_t.
+ */
+int msm_gem_get_iova_locked(struct drm_gem_object *obj, int id,
+ uint32_t *iova)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ int ret = 0;
+
+ if (!msm_obj->domain[id].iova) {
+ struct msm_drm_private *priv = obj->dev->dev_private;
+ struct page **pages = get_pages(obj);
+
+ if (IS_ERR(pages))
+ return PTR_ERR(pages);
+
+ if (iommu_present(&platform_bus_type)) {
+ struct msm_mmu *mmu = priv->mmus[id];
+ uint32_t offset;
+
+ if (WARN_ON(!mmu))
+ return -EINVAL;
+
+ offset = (uint32_t)mmap_offset(obj);
+ ret = mmu->funcs->map(mmu, offset, msm_obj->sgt,
+ obj->size, IOMMU_READ | IOMMU_WRITE);
+ msm_obj->domain[id].iova = offset;
+ } else {
+ msm_obj->domain[id].iova = physaddr(obj);
+ }
+ }
+
+ if (!ret)
+ *iova = msm_obj->domain[id].iova;
+
+ return ret;
+}
+
+/* get iova, taking a reference. Should have a matching put */
+int msm_gem_get_iova(struct drm_gem_object *obj, int id, uint32_t *iova)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ int ret;
+
+ /* this is safe right now because we don't unmap until the
+ * bo is deleted:
+ */
+ if (msm_obj->domain[id].iova) {
+ *iova = msm_obj->domain[id].iova;
+ return 0;
+ }
+
+ mutex_lock(&obj->dev->struct_mutex);
+ ret = msm_gem_get_iova_locked(obj, id, iova);
+ mutex_unlock(&obj->dev->struct_mutex);
+ return ret;
+}
+
+/* get iova without taking a reference, used in places where you have
+ * already done a 'msm_gem_get_iova()'.
+ */
+uint32_t msm_gem_iova(struct drm_gem_object *obj, int id)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ WARN_ON(!msm_obj->domain[id].iova);
+ return msm_obj->domain[id].iova;
+}
+
+void msm_gem_put_iova(struct drm_gem_object *obj, int id)
+{
+ // XXX TODO ..
+ // NOTE: probably don't need a _locked() version.. we wouldn't
+ // normally unmap here, but instead just mark that it could be
+ // unmapped (if the iova refcnt drops to zero), but then later
+ // if another _get_iova_locked() fails we can start unmapping
+ // things that are no longer needed..
+}
+
+int msm_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
+ struct drm_mode_create_dumb *args)
+{
+ args->pitch = align_pitch(args->width, args->bpp);
+ args->size = PAGE_ALIGN(args->pitch * args->height);
+ return msm_gem_new_handle(dev, file, args->size,
+ MSM_BO_SCANOUT | MSM_BO_WC, &args->handle);
+}
+
+int msm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
+ uint32_t handle, uint64_t *offset)
+{
+ struct drm_gem_object *obj;
+ int ret = 0;
+
+ /* GEM does all our handle to object mapping */
+ obj = drm_gem_object_lookup(dev, file, handle);
+ if (obj == NULL) {
+ ret = -ENOENT;
+ goto fail;
+ }
+
+ *offset = msm_gem_mmap_offset(obj);
+
+ drm_gem_object_unreference_unlocked(obj);
+
+fail:
+ return ret;
+}
+
+void *msm_gem_vaddr_locked(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ if (!msm_obj->vaddr) {
+ struct page **pages = get_pages(obj);
+ if (IS_ERR(pages))
+ return ERR_CAST(pages);
+ msm_obj->vaddr = vmap(pages, obj->size >> PAGE_SHIFT,
+ VM_MAP, pgprot_writecombine(PAGE_KERNEL));
+ }
+ return msm_obj->vaddr;
+}
+
+void *msm_gem_vaddr(struct drm_gem_object *obj)
+{
+ void *ret;
+ mutex_lock(&obj->dev->struct_mutex);
+ ret = msm_gem_vaddr_locked(obj);
+ mutex_unlock(&obj->dev->struct_mutex);
+ return ret;
+}
+
+/* setup callback for when bo is no longer busy..
+ * TODO probably want to differentiate read vs write..
+ */
+int msm_gem_queue_inactive_cb(struct drm_gem_object *obj,
+ struct msm_fence_cb *cb)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ uint32_t fence = msm_gem_fence(msm_obj,
+ MSM_PREP_READ | MSM_PREP_WRITE);
+ return msm_queue_fence_cb(obj->dev, cb, fence);
+}
+
+void msm_gem_move_to_active(struct drm_gem_object *obj,
+ struct msm_gpu *gpu, bool write, uint32_t fence)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ msm_obj->gpu = gpu;
+ if (write)
+ msm_obj->write_fence = fence;
+ else
+ msm_obj->read_fence = fence;
+ list_del_init(&msm_obj->mm_list);
+ list_add_tail(&msm_obj->mm_list, &gpu->active_list);
+}
+
+void msm_gem_move_to_inactive(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj->dev;
+ struct msm_drm_private *priv = dev->dev_private;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+ msm_obj->gpu = NULL;
+ msm_obj->read_fence = 0;
+ msm_obj->write_fence = 0;
+ list_del_init(&msm_obj->mm_list);
+ list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
+}
+
+int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op,
+ struct timespec *timeout)
+{
+ struct drm_device *dev = obj->dev;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ int ret = 0;
+
+ if (is_active(msm_obj)) {
+ uint32_t fence = msm_gem_fence(msm_obj, op);
+
+ if (op & MSM_PREP_NOSYNC)
+ timeout = NULL;
+
+ ret = msm_wait_fence_interruptable(dev, fence, timeout);
+ }
+
+ /* TODO cache maintenance */
+
+ return ret;
+}
+
+int msm_gem_cpu_fini(struct drm_gem_object *obj)
+{
+ /* TODO cache maintenance */
+ return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
+{
+ struct drm_device *dev = obj->dev;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ uint64_t off = drm_vma_node_start(&obj->vma_node);
+
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+ seq_printf(m, "%08x: %c(r=%u,w=%u) %2d (%2d) %08llx %p %zu\n",
+ msm_obj->flags, is_active(msm_obj) ? 'A' : 'I',
+ msm_obj->read_fence, msm_obj->write_fence,
+ obj->name, obj->refcount.refcount.counter,
+ off, msm_obj->vaddr, obj->size);
+}
+
+void msm_gem_describe_objects(struct list_head *list, struct seq_file *m)
+{
+ struct msm_gem_object *msm_obj;
+ int count = 0;
+ size_t size = 0;
+
+ list_for_each_entry(msm_obj, list, mm_list) {
+ struct drm_gem_object *obj = &msm_obj->base;
+ seq_printf(m, " ");
+ msm_gem_describe(obj, m);
+ count++;
+ size += obj->size;
+ }
+
+ seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
+}
+#endif
+
+void msm_gem_free_object(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj->dev;
+ struct msm_drm_private *priv = obj->dev->dev_private;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ int id;
+
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+ /* object should not be on active list: */
+ WARN_ON(is_active(msm_obj));
+
+ list_del(&msm_obj->mm_list);
+
+ for (id = 0; id < ARRAY_SIZE(msm_obj->domain); id++) {
+ struct msm_mmu *mmu = priv->mmus[id];
+ if (mmu && msm_obj->domain[id].iova) {
+ uint32_t offset = msm_obj->domain[id].iova;
+ mmu->funcs->unmap(mmu, offset, msm_obj->sgt, obj->size);
+ }
+ }
+
+ if (obj->import_attach) {
+ if (msm_obj->vaddr)
+ dma_buf_vunmap(obj->import_attach->dmabuf, msm_obj->vaddr);
+
+ /* Don't drop the pages for imported dmabuf, as they are not
+ * ours, just free the array we allocated:
+ */
+ if (msm_obj->pages)
+ drm_free_large(msm_obj->pages);
+
+ } else {
+ vunmap(msm_obj->vaddr);
+ put_pages(obj);
+ }
+
+ if (msm_obj->resv == &msm_obj->_resv)
+ reservation_object_fini(msm_obj->resv);
+
+ drm_gem_object_release(obj);
+
+ kfree(msm_obj);
+}
+
+/* convenience method to construct a GEM buffer object, and userspace handle */
+int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
+ uint32_t size, uint32_t flags, uint32_t *handle)
+{
+ struct drm_gem_object *obj;
+ int ret;
+
+ ret = mutex_lock_interruptible(&dev->struct_mutex);
+ if (ret)
+ return ret;
+
+ obj = msm_gem_new(dev, size, flags);
+
+ mutex_unlock(&dev->struct_mutex);
+
+ if (IS_ERR(obj))
+ return PTR_ERR(obj);
+
+ ret = drm_gem_handle_create(file, obj, handle);
+
+ /* drop reference from allocate - handle holds it now */
+ drm_gem_object_unreference_unlocked(obj);
+
+ return ret;
+}
+
+static int msm_gem_new_impl(struct drm_device *dev,
+ uint32_t size, uint32_t flags,
+ struct drm_gem_object **obj)
+{
+ struct msm_drm_private *priv = dev->dev_private;
+ struct msm_gem_object *msm_obj;
+ unsigned sz;
+ bool use_vram = false;
+
+ switch (flags & MSM_BO_CACHE_MASK) {
+ case MSM_BO_UNCACHED:
+ case MSM_BO_CACHED:
+ case MSM_BO_WC:
+ break;
+ default:
+ dev_err(dev->dev, "invalid cache flag: %x\n",
+ (flags & MSM_BO_CACHE_MASK));
+ return -EINVAL;
+ }
+
+ if (!iommu_present(&platform_bus_type))
+ use_vram = true;
+ else if ((flags & MSM_BO_STOLEN) && priv->vram.size)
+ use_vram = true;
+
+ if (WARN_ON(use_vram && !priv->vram.size))
+ return -EINVAL;
+
+ sz = sizeof(*msm_obj);
+ if (use_vram)
+ sz += sizeof(struct drm_mm_node);
+
+ msm_obj = kzalloc(sz, GFP_KERNEL);
+ if (!msm_obj)
+ return -ENOMEM;
+
+ if (use_vram)
+ msm_obj->vram_node = (void *)&msm_obj[1];
+
+ msm_obj->flags = flags;
+
+ msm_obj->resv = &msm_obj->_resv;
+ reservation_object_init(msm_obj->resv);
+
+ INIT_LIST_HEAD(&msm_obj->submit_entry);
+ list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
+
+ *obj = &msm_obj->base;
+
+ return 0;
+}
+
+struct drm_gem_object *msm_gem_new(struct drm_device *dev,
+ uint32_t size, uint32_t flags)
+{
+ struct drm_gem_object *obj = NULL;
+ int ret;
+
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+ size = PAGE_ALIGN(size);
+
+ ret = msm_gem_new_impl(dev, size, flags, &obj);
+ if (ret)
+ goto fail;
+
+ if (use_pages(obj)) {
+ ret = drm_gem_object_init(dev, obj, size);
+ if (ret)
+ goto fail;
+ } else {
+ drm_gem_private_object_init(dev, obj, size);
+ }
+
+ return obj;
+
+fail:
+ if (obj)
+ drm_gem_object_unreference(obj);
+
+ return ERR_PTR(ret);
+}
+
+struct drm_gem_object *msm_gem_import(struct drm_device *dev,
+ uint32_t size, struct sg_table *sgt)
+{
+ struct msm_gem_object *msm_obj;
+ struct drm_gem_object *obj;
+ int ret, npages;
+
+ /* if we don't have IOMMU, don't bother pretending we can import: */
+ if (!iommu_present(&platform_bus_type)) {
+ dev_err(dev->dev, "cannot import without IOMMU\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ size = PAGE_ALIGN(size);
+
+ ret = msm_gem_new_impl(dev, size, MSM_BO_WC, &obj);
+ if (ret)
+ goto fail;
+
+ drm_gem_private_object_init(dev, obj, size);
+
+ npages = size / PAGE_SIZE;
+
+ msm_obj = to_msm_bo(obj);
+ msm_obj->sgt = sgt;
+ msm_obj->pages = drm_malloc_ab(npages, sizeof(struct page *));
+ if (!msm_obj->pages) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ ret = drm_prime_sg_to_page_addr_arrays(sgt, msm_obj->pages, NULL, npages);
+ if (ret)
+ goto fail;
+
+ return obj;
+
+fail:
+ if (obj)
+ drm_gem_object_unreference_unlocked(obj);
+
+ return ERR_PTR(ret);
+}