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authorJohn Hubbard <jhubbard@nvidia.com>2020-01-30 22:13:35 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-01-31 10:30:38 -0800
commitf1f6a7dd9b53aafd81b696b9017036e7b08e57ea (patch)
tree6bede48988d6b4cae3c9b2dbb986c0725f526743
parentbdffe23eee672fcaa732198c3661f7c1302c6bfa (diff)
downloadlwn-f1f6a7dd9b53aafd81b696b9017036e7b08e57ea.tar.gz
lwn-f1f6a7dd9b53aafd81b696b9017036e7b08e57ea.zip
mm, tree-wide: rename put_user_page*() to unpin_user_page*()
In order to provide a clearer, more symmetric API for pinning and unpinning DMA pages. This way, pin_user_pages*() calls match up with unpin_user_pages*() calls, and the API is a lot closer to being self-explanatory. Link: http://lkml.kernel.org/r/20200107224558.2362728-23-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--Documentation/core-api/pin_user_pages.rst2
-rw-r--r--arch/powerpc/mm/book3s64/iommu_api.c4
-rw-r--r--drivers/gpu/drm/via/via_dmablit.c4
-rw-r--r--drivers/infiniband/core/umem.c2
-rw-r--r--drivers/infiniband/hw/hfi1/user_pages.c2
-rw-r--r--drivers/infiniband/hw/mthca/mthca_memfree.c6
-rw-r--r--drivers/infiniband/hw/qib/qib_user_pages.c2
-rw-r--r--drivers/infiniband/hw/qib/qib_user_sdma.c6
-rw-r--r--drivers/infiniband/hw/usnic/usnic_uiom.c2
-rw-r--r--drivers/infiniband/sw/siw/siw_mem.c2
-rw-r--r--drivers/media/v4l2-core/videobuf-dma-sg.c4
-rw-r--r--drivers/platform/goldfish/goldfish_pipe.c4
-rw-r--r--drivers/vfio/vfio_iommu_type1.c2
-rw-r--r--fs/io_uring.c4
-rw-r--r--include/linux/mm.h26
-rw-r--r--mm/gup.c32
-rw-r--r--mm/process_vm_access.c4
-rw-r--r--net/xdp/xdp_umem.c2
18 files changed, 55 insertions, 55 deletions
diff --git a/Documentation/core-api/pin_user_pages.rst b/Documentation/core-api/pin_user_pages.rst
index 71849830cd48..1d490155ecd7 100644
--- a/Documentation/core-api/pin_user_pages.rst
+++ b/Documentation/core-api/pin_user_pages.rst
@@ -219,7 +219,7 @@ since the system was booted, via two new /proc/vmstat entries: ::
/proc/vmstat/nr_foll_pin_requested
Those are both going to show zero, unless CONFIG_DEBUG_VM is set. This is
-because there is a noticeable performance drop in put_user_page(), when they
+because there is a noticeable performance drop in unpin_user_page(), when they
are activated.
References
diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c
index a86547822034..eba73ebd8ae5 100644
--- a/arch/powerpc/mm/book3s64/iommu_api.c
+++ b/arch/powerpc/mm/book3s64/iommu_api.c
@@ -168,7 +168,7 @@ good_exit:
free_exit:
/* free the references taken */
- put_user_pages(mem->hpages, pinned);
+ unpin_user_pages(mem->hpages, pinned);
vfree(mem->hpas);
kfree(mem);
@@ -214,7 +214,7 @@ static void mm_iommu_unpin(struct mm_iommu_table_group_mem_t *mem)
if (mem->hpas[i] & MM_IOMMU_TABLE_GROUP_PAGE_DIRTY)
SetPageDirty(page);
- put_user_page(page);
+ unpin_user_page(page);
mem->hpas[i] = 0;
}
diff --git a/drivers/gpu/drm/via/via_dmablit.c b/drivers/gpu/drm/via/via_dmablit.c
index 37c5e572993a..719d036c9384 100644
--- a/drivers/gpu/drm/via/via_dmablit.c
+++ b/drivers/gpu/drm/via/via_dmablit.c
@@ -188,8 +188,8 @@ via_free_sg_info(struct pci_dev *pdev, drm_via_sg_info_t *vsg)
kfree(vsg->desc_pages);
/* fall through */
case dr_via_pages_locked:
- put_user_pages_dirty_lock(vsg->pages, vsg->num_pages,
- (vsg->direction == DMA_FROM_DEVICE));
+ unpin_user_pages_dirty_lock(vsg->pages, vsg->num_pages,
+ (vsg->direction == DMA_FROM_DEVICE));
/* fall through */
case dr_via_pages_alloc:
vfree(vsg->pages);
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index aae5bfed7f3b..c3769a5f096d 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -54,7 +54,7 @@ static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int d
for_each_sg_page(umem->sg_head.sgl, &sg_iter, umem->sg_nents, 0) {
page = sg_page_iter_page(&sg_iter);
- put_user_pages_dirty_lock(&page, 1, umem->writable && dirty);
+ unpin_user_pages_dirty_lock(&page, 1, umem->writable && dirty);
}
sg_free_table(&umem->sg_head);
diff --git a/drivers/infiniband/hw/hfi1/user_pages.c b/drivers/infiniband/hw/hfi1/user_pages.c
index 9a94761765c0..3b505006c0a6 100644
--- a/drivers/infiniband/hw/hfi1/user_pages.c
+++ b/drivers/infiniband/hw/hfi1/user_pages.c
@@ -118,7 +118,7 @@ int hfi1_acquire_user_pages(struct mm_struct *mm, unsigned long vaddr, size_t np
void hfi1_release_user_pages(struct mm_struct *mm, struct page **p,
size_t npages, bool dirty)
{
- put_user_pages_dirty_lock(p, npages, dirty);
+ unpin_user_pages_dirty_lock(p, npages, dirty);
if (mm) { /* during close after signal, mm can be NULL */
atomic64_sub(npages, &mm->pinned_vm);
diff --git a/drivers/infiniband/hw/mthca/mthca_memfree.c b/drivers/infiniband/hw/mthca/mthca_memfree.c
index 8269ab040c21..78a48aea3faf 100644
--- a/drivers/infiniband/hw/mthca/mthca_memfree.c
+++ b/drivers/infiniband/hw/mthca/mthca_memfree.c
@@ -482,7 +482,7 @@ int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
if (ret < 0) {
- put_user_page(pages[0]);
+ unpin_user_page(pages[0]);
goto out;
}
@@ -490,7 +490,7 @@ int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
mthca_uarc_virt(dev, uar, i));
if (ret) {
pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
- put_user_page(sg_page(&db_tab->page[i].mem));
+ unpin_user_page(sg_page(&db_tab->page[i].mem));
goto out;
}
@@ -556,7 +556,7 @@ void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
if (db_tab->page[i].uvirt) {
mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, uar, i), 1);
pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
- put_user_page(sg_page(&db_tab->page[i].mem));
+ unpin_user_page(sg_page(&db_tab->page[i].mem));
}
}
diff --git a/drivers/infiniband/hw/qib/qib_user_pages.c b/drivers/infiniband/hw/qib/qib_user_pages.c
index 7fc4b5f81fcd..342e3172ca40 100644
--- a/drivers/infiniband/hw/qib/qib_user_pages.c
+++ b/drivers/infiniband/hw/qib/qib_user_pages.c
@@ -40,7 +40,7 @@
static void __qib_release_user_pages(struct page **p, size_t num_pages,
int dirty)
{
- put_user_pages_dirty_lock(p, num_pages, dirty);
+ unpin_user_pages_dirty_lock(p, num_pages, dirty);
}
/**
diff --git a/drivers/infiniband/hw/qib/qib_user_sdma.c b/drivers/infiniband/hw/qib/qib_user_sdma.c
index 1a3cc2957e3a..a67599b5a550 100644
--- a/drivers/infiniband/hw/qib/qib_user_sdma.c
+++ b/drivers/infiniband/hw/qib/qib_user_sdma.c
@@ -317,7 +317,7 @@ static int qib_user_sdma_page_to_frags(const struct qib_devdata *dd,
* the caller can ignore this page.
*/
if (put) {
- put_user_page(page);
+ unpin_user_page(page);
} else {
/* coalesce case */
kunmap(page);
@@ -631,7 +631,7 @@ static void qib_user_sdma_free_pkt_frag(struct device *dev,
kunmap(pkt->addr[i].page);
if (pkt->addr[i].put_page)
- put_user_page(pkt->addr[i].page);
+ unpin_user_page(pkt->addr[i].page);
else
__free_page(pkt->addr[i].page);
} else if (pkt->addr[i].kvaddr) {
@@ -706,7 +706,7 @@ static int qib_user_sdma_pin_pages(const struct qib_devdata *dd,
/* if error, return all pages not managed by pkt */
free_pages:
while (i < j)
- put_user_page(pages[i++]);
+ unpin_user_page(pages[i++]);
done:
return ret;
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c
index 600896727d34..bd9f944b68fc 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.c
@@ -75,7 +75,7 @@ static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty)
for_each_sg(chunk->page_list, sg, chunk->nents, i) {
page = sg_page(sg);
pa = sg_phys(sg);
- put_user_pages_dirty_lock(&page, 1, dirty);
+ unpin_user_pages_dirty_lock(&page, 1, dirty);
usnic_dbg("pa: %pa\n", &pa);
}
kfree(chunk);
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
index e53b07dcfed5..e2061dc0b043 100644
--- a/drivers/infiniband/sw/siw/siw_mem.c
+++ b/drivers/infiniband/sw/siw/siw_mem.c
@@ -63,7 +63,7 @@ struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index)
static void siw_free_plist(struct siw_page_chunk *chunk, int num_pages,
bool dirty)
{
- put_user_pages_dirty_lock(chunk->plist, num_pages, dirty);
+ unpin_user_pages_dirty_lock(chunk->plist, num_pages, dirty);
}
void siw_umem_release(struct siw_umem *umem, bool dirty)
diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2-core/videobuf-dma-sg.c
index 162a2633b1e3..13b65ed9e74c 100644
--- a/drivers/media/v4l2-core/videobuf-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
@@ -349,8 +349,8 @@ int videobuf_dma_free(struct videobuf_dmabuf *dma)
BUG_ON(dma->sglen);
if (dma->pages) {
- put_user_pages_dirty_lock(dma->pages, dma->nr_pages,
- dma->direction == DMA_FROM_DEVICE);
+ unpin_user_pages_dirty_lock(dma->pages, dma->nr_pages,
+ dma->direction == DMA_FROM_DEVICE);
kfree(dma->pages);
dma->pages = NULL;
}
diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c
index 2a5901efecde..1ab207ec9c94 100644
--- a/drivers/platform/goldfish/goldfish_pipe.c
+++ b/drivers/platform/goldfish/goldfish_pipe.c
@@ -360,8 +360,8 @@ static int transfer_max_buffers(struct goldfish_pipe *pipe,
*consumed_size = pipe->command_buffer->rw_params.consumed_size;
- put_user_pages_dirty_lock(pipe->pages, pages_count,
- !is_write && *consumed_size > 0);
+ unpin_user_pages_dirty_lock(pipe->pages, pages_count,
+ !is_write && *consumed_size > 0);
mutex_unlock(&pipe->lock);
return 0;
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 18bfc2fc8e6d..a177bf2c6683 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -310,7 +310,7 @@ static int put_pfn(unsigned long pfn, int prot)
if (!is_invalid_reserved_pfn(pfn)) {
struct page *page = pfn_to_page(pfn);
- put_user_pages_dirty_lock(&page, 1, prot & IOMMU_WRITE);
+ unpin_user_pages_dirty_lock(&page, 1, prot & IOMMU_WRITE);
return 1;
}
return 0;
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 54f664e8b9b8..1806afddfea5 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6005,7 +6005,7 @@ static int io_sqe_buffer_unregister(struct io_ring_ctx *ctx)
struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
for (j = 0; j < imu->nr_bvecs; j++)
- put_user_page(imu->bvec[j].bv_page);
+ unpin_user_page(imu->bvec[j].bv_page);
if (ctx->account_mem)
io_unaccount_mem(ctx->user, imu->nr_bvecs);
@@ -6150,7 +6150,7 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg,
* release any pages we did get
*/
if (pret > 0)
- put_user_pages(pages, pret);
+ unpin_user_pages(pages, pret);
if (ctx->account_mem)
io_unaccount_mem(ctx->user, nr_pages);
kvfree(imu->bvec);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 79ca557349c6..fc543eb45de1 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1039,27 +1039,27 @@ static inline void put_page(struct page *page)
}
/**
- * put_user_page() - release a gup-pinned page
+ * unpin_user_page() - release a gup-pinned page
* @page: pointer to page to be released
*
* Pages that were pinned via pin_user_pages*() must be released via either
- * put_user_page(), or one of the put_user_pages*() routines. This is so that
- * eventually such pages can be separately tracked and uniquely handled. In
+ * unpin_user_page(), or one of the unpin_user_pages*() routines. This is so
+ * that eventually such pages can be separately tracked and uniquely handled. In
* particular, interactions with RDMA and filesystems need special handling.
*
- * put_user_page() and put_page() are not interchangeable, despite this early
- * implementation that makes them look the same. put_user_page() calls must
+ * unpin_user_page() and put_page() are not interchangeable, despite this early
+ * implementation that makes them look the same. unpin_user_page() calls must
* be perfectly matched up with pin*() calls.
*/
-static inline void put_user_page(struct page *page)
+static inline void unpin_user_page(struct page *page)
{
put_page(page);
}
-void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
- bool make_dirty);
+void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
+ bool make_dirty);
-void put_user_pages(struct page **pages, unsigned long npages);
+void unpin_user_pages(struct page **pages, unsigned long npages);
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
#define SECTION_IN_PAGE_FLAGS
@@ -2590,7 +2590,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
#define FOLL_ANON 0x8000 /* don't do file mappings */
#define FOLL_LONGTERM 0x10000 /* mapping lifetime is indefinite: see below */
#define FOLL_SPLIT_PMD 0x20000 /* split huge pmd before returning */
-#define FOLL_PIN 0x40000 /* pages must be released via put_user_page() */
+#define FOLL_PIN 0x40000 /* pages must be released via unpin_user_page */
/*
* FOLL_PIN and FOLL_LONGTERM may be used in various combinations with each
@@ -2625,7 +2625,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
* Direct IO). This lets the filesystem know that some non-file-system entity is
* potentially changing the pages' data. In contrast to FOLL_GET (whose pages
* are released via put_page()), FOLL_PIN pages must be released, ultimately, by
- * a call to put_user_page().
+ * a call to unpin_user_page().
*
* FOLL_PIN is similar to FOLL_GET: both of these pin pages. They use different
* and separate refcounting mechanisms, however, and that means that each has
@@ -2633,7 +2633,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
*
* FOLL_GET: get_user_pages*() to acquire, and put_page() to release.
*
- * FOLL_PIN: pin_user_pages*() to acquire, and put_user_pages to release.
+ * FOLL_PIN: pin_user_pages*() to acquire, and unpin_user_pages to release.
*
* FOLL_PIN and FOLL_GET are mutually exclusive for a given function call.
* (The underlying pages may experience both FOLL_GET-based and FOLL_PIN-based
@@ -2643,7 +2643,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
* FOLL_PIN should be set internally by the pin_user_pages*() APIs, never
* directly by the caller. That's in order to help avoid mismatches when
* releasing pages: get_user_pages*() pages must be released via put_page(),
- * while pin_user_pages*() pages must be released via put_user_page().
+ * while pin_user_pages*() pages must be released via unpin_user_page().
*
* Please see Documentation/vm/pin_user_pages.rst for more information.
*/
diff --git a/mm/gup.c b/mm/gup.c
index cc7e78f4a960..e13f4d211475 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -45,7 +45,7 @@ static inline struct page *try_get_compound_head(struct page *page, int refs)
}
/**
- * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages
+ * unpin_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages
* @pages: array of pages to be maybe marked dirty, and definitely released.
* @npages: number of pages in the @pages array.
* @make_dirty: whether to mark the pages dirty
@@ -55,19 +55,19 @@ static inline struct page *try_get_compound_head(struct page *page, int refs)
*
* For each page in the @pages array, make that page (or its head page, if a
* compound page) dirty, if @make_dirty is true, and if the page was previously
- * listed as clean. In any case, releases all pages using put_user_page(),
- * possibly via put_user_pages(), for the non-dirty case.
+ * listed as clean. In any case, releases all pages using unpin_user_page(),
+ * possibly via unpin_user_pages(), for the non-dirty case.
*
- * Please see the put_user_page() documentation for details.
+ * Please see the unpin_user_page() documentation for details.
*
* set_page_dirty_lock() is used internally. If instead, set_page_dirty() is
* required, then the caller should a) verify that this is really correct,
* because _lock() is usually required, and b) hand code it:
- * set_page_dirty_lock(), put_user_page().
+ * set_page_dirty_lock(), unpin_user_page().
*
*/
-void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
- bool make_dirty)
+void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
+ bool make_dirty)
{
unsigned long index;
@@ -78,7 +78,7 @@ void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
*/
if (!make_dirty) {
- put_user_pages(pages, npages);
+ unpin_user_pages(pages, npages);
return;
}
@@ -106,21 +106,21 @@ void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
*/
if (!PageDirty(page))
set_page_dirty_lock(page);
- put_user_page(page);
+ unpin_user_page(page);
}
}
-EXPORT_SYMBOL(put_user_pages_dirty_lock);
+EXPORT_SYMBOL(unpin_user_pages_dirty_lock);
/**
- * put_user_pages() - release an array of gup-pinned pages.
+ * unpin_user_pages() - release an array of gup-pinned pages.
* @pages: array of pages to be marked dirty and released.
* @npages: number of pages in the @pages array.
*
- * For each page in the @pages array, release the page using put_user_page().
+ * For each page in the @pages array, release the page using unpin_user_page().
*
- * Please see the put_user_page() documentation for details.
+ * Please see the unpin_user_page() documentation for details.
*/
-void put_user_pages(struct page **pages, unsigned long npages)
+void unpin_user_pages(struct page **pages, unsigned long npages)
{
unsigned long index;
@@ -130,9 +130,9 @@ void put_user_pages(struct page **pages, unsigned long npages)
* single operation to the head page should suffice.
*/
for (index = 0; index < npages; index++)
- put_user_page(pages[index]);
+ unpin_user_page(pages[index]);
}
-EXPORT_SYMBOL(put_user_pages);
+EXPORT_SYMBOL(unpin_user_pages);
#ifdef CONFIG_MMU
static struct page *no_page_table(struct vm_area_struct *vma,
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index fd20ab675b85..de41e830cdac 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -126,8 +126,8 @@ static int process_vm_rw_single_vec(unsigned long addr,
pa += pinned_pages * PAGE_SIZE;
/* If vm_write is set, the pages need to be made dirty: */
- put_user_pages_dirty_lock(process_pages, pinned_pages,
- vm_write);
+ unpin_user_pages_dirty_lock(process_pages, pinned_pages,
+ vm_write);
}
return rc;
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index b17ce9a5534d..fa7bb5e060d0 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -212,7 +212,7 @@ static int xdp_umem_map_pages(struct xdp_umem *umem)
static void xdp_umem_unpin_pages(struct xdp_umem *umem)
{
- put_user_pages_dirty_lock(umem->pgs, umem->npgs, true);
+ unpin_user_pages_dirty_lock(umem->pgs, umem->npgs, true);
kfree(umem->pgs);
umem->pgs = NULL;