From: Mateusz Polrola mateuszx.potrola@intel.com
It is needed to freeing already-mapped pages if it gets error before finishing mapping all pages.
Signed-off-by: Dongwon Kim dongwon.kim@intel.com --- .../xen/hyper_dmabuf/xen/hyper_dmabuf_xen_shm.c | 43 +++++++++++++++++++--- 1 file changed, 38 insertions(+), 5 deletions(-)
diff --git a/drivers/xen/hyper_dmabuf/xen/hyper_dmabuf_xen_shm.c b/drivers/xen/hyper_dmabuf/xen/hyper_dmabuf_xen_shm.c index c03e5a0..524f75c 100644 --- a/drivers/xen/hyper_dmabuf/xen/hyper_dmabuf_xen_shm.c +++ b/drivers/xen/hyper_dmabuf/xen/hyper_dmabuf_xen_shm.c @@ -255,7 +255,7 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n if (lvl3_map_ops.status) { dev_err(hyper_dmabuf_private.device, "HYPERVISOR map grant ref failed status = %d", lvl3_map_ops.status); - return NULL; + goto error_cleanup_lvl3; } else { lvl3_unmap_ops.handle = lvl3_map_ops.handle; } @@ -263,7 +263,7 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n /* Map all second level pages */ if (gnttab_alloc_pages(n_lvl2_grefs, lvl2_table_pages)) { dev_err(hyper_dmabuf_private.device, "Cannot allocate pages\n"); - return NULL; + goto error_cleanup_lvl3; }
for (i = 0; i < n_lvl2_grefs; i++) { @@ -277,6 +277,9 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n if (gnttab_unmap_refs(&lvl3_unmap_ops, NULL, &lvl3_table_page, 1)) { dev_err(hyper_dmabuf_private.device, "xen: cannot unmap top level page\n"); return NULL; + } else { + /* Mark that page was unmapped */ + lvl3_unmap_ops.handle = -1; }
if (gnttab_map_refs(lvl2_map_ops, NULL, lvl2_table_pages, n_lvl2_grefs)) { @@ -290,7 +293,7 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n dev_err(hyper_dmabuf_private.device, "HYPERVISOR map grant ref failed status = %d", lvl2_map_ops[i].status); - return NULL; + goto error_cleanup_lvl2; } else { lvl2_unmap_ops[i].handle = lvl2_map_ops[i].handle; } @@ -298,7 +301,7 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n
if (gnttab_alloc_pages(nents, data_pages)) { dev_err(hyper_dmabuf_private.device, "Cannot allocate pages\n"); - return NULL; + goto error_cleanup_lvl2; }
k = 0; @@ -343,6 +346,11 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n n_lvl2_grefs)) { dev_err(hyper_dmabuf_private.device, "Cannot unmap 2nd level refs\n"); return NULL; + } else { + /* Mark that pages were unmapped */ + for (i = 0; i < n_lvl2_grefs; i++) { + lvl2_unmap_ops[i].handle = -1; + } }
for (i = 0; i < nents; i++) { @@ -350,7 +358,7 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n dev_err(hyper_dmabuf_private.device, "HYPERVISOR map grant ref failed status = %d\n", data_map_ops[i].status); - return NULL; + goto error_cleanup_data; } else { data_unmap_ops[i].handle = data_map_ops[i].handle; } @@ -369,6 +377,31 @@ struct page ** hyper_dmabuf_xen_map_shared_pages(int lvl3_gref, int domid, int n
dev_dbg(hyper_dmabuf_private.device, "%s exit\n", __func__); return data_pages; + +error_cleanup_data: + gnttab_unmap_refs(data_unmap_ops, NULL, data_pages, + nents); + + gnttab_free_pages(nents, data_pages); + +error_cleanup_lvl2: + if (lvl2_unmap_ops[0].handle != -1) + gnttab_unmap_refs(lvl2_unmap_ops, NULL, lvl2_table_pages, + n_lvl2_grefs); + gnttab_free_pages(n_lvl2_grefs, lvl2_table_pages); + +error_cleanup_lvl3: + if (lvl3_unmap_ops.handle != -1) + gnttab_unmap_refs(&lvl3_unmap_ops, NULL, &lvl3_table_page, 1); + gnttab_free_pages(1, &lvl3_table_page); + + kfree(lvl2_table_pages); + kfree(lvl2_map_ops); + kfree(lvl2_unmap_ops); + kfree(data_map_ops); + + + return NULL; }
int hyper_dmabuf_xen_unmap_shared_pages(void **refs_info, int nents) {