diff options
Diffstat (limited to 'drivers/xen/xen-front-pgdir-shbuf.c')
-rw-r--r-- | drivers/xen/xen-front-pgdir-shbuf.c | 36 |
1 files changed, 17 insertions, 19 deletions
diff --git a/drivers/xen/xen-front-pgdir-shbuf.c b/drivers/xen/xen-front-pgdir-shbuf.c index 48a658dc7ccf..5c0b5cb5b419 100644 --- a/drivers/xen/xen-front-pgdir-shbuf.c +++ b/drivers/xen/xen-front-pgdir-shbuf.c @@ -21,15 +21,6 @@ #include <xen/xen-front-pgdir-shbuf.h> -#ifndef GRANT_INVALID_REF -/* - * FIXME: usage of grant reference 0 as invalid grant reference: - * grant reference 0 is valid, but never exposed to a PV driver, - * because of the fact it is already in use/reserved by the PV console. - */ -#define GRANT_INVALID_REF 0 -#endif - /** * This structure represents the structure of a shared page * that contains grant references to the pages of the shared @@ -38,6 +29,7 @@ */ struct xen_page_directory { grant_ref_t gref_dir_next_page; +#define XEN_GREF_LIST_END 0 grant_ref_t gref[1]; /* Variable length */ }; @@ -83,7 +75,7 @@ grant_ref_t xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf) { if (!buf->grefs) - return GRANT_INVALID_REF; + return INVALID_GRANT_REF; return buf->grefs[0]; } @@ -97,7 +89,7 @@ EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_get_dir_start); * shared by the frontend itself) or map the provided granted * references onto the backing storage (buf->pages). * - * \param buf shared buffer which grants to be maped. + * \param buf shared buffer which grants to be mapped. * \return zero on success or a negative number on failure. */ int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf) @@ -118,7 +110,7 @@ EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_map); * shared by the frontend itself) or unmap the provided granted * references. * - * \param buf shared buffer which grants to be unmaped. + * \param buf shared buffer which grants to be unmapped. * \return zero on success or a negative number on failure. */ int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf) @@ -142,9 +134,8 @@ void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_shbuf *buf) int i; for (i = 0; i < buf->num_grefs; i++) - if (buf->grefs[i] != GRANT_INVALID_REF) - gnttab_end_foreign_access(buf->grefs[i], - 0, 0UL); + if (buf->grefs[i] != INVALID_GRANT_REF) + gnttab_end_foreign_access(buf->grefs[i], NULL); } kfree(buf->grefs); kfree(buf->directory); @@ -305,11 +296,18 @@ static int backend_map(struct xen_front_pgdir_shbuf *buf) /* Save handles even if error, so we can unmap. */ for (cur_page = 0; cur_page < buf->num_pages; cur_page++) { - buf->backend_map_handles[cur_page] = map_ops[cur_page].handle; - if (unlikely(map_ops[cur_page].status != GNTST_okay)) + if (likely(map_ops[cur_page].status == GNTST_okay)) { + buf->backend_map_handles[cur_page] = + map_ops[cur_page].handle; + } else { + buf->backend_map_handles[cur_page] = + INVALID_GRANT_HANDLE; + if (!ret) + ret = -ENXIO; dev_err(&buf->xb_dev->dev, "Failed to map page %d: %d\n", cur_page, map_ops[cur_page].status); + } } if (ret) { @@ -349,7 +347,7 @@ static void backend_fill_page_dir(struct xen_front_pgdir_shbuf *buf) } /* Last page must say there is no more pages. */ page_dir = (struct xen_page_directory *)ptr; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; + page_dir->gref_dir_next_page = XEN_GREF_LIST_END; } /** @@ -378,7 +376,7 @@ static void guest_fill_page_dir(struct xen_front_pgdir_shbuf *buf) if (grefs_left <= XEN_NUM_GREFS_PER_PAGE) { to_copy = grefs_left; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; + page_dir->gref_dir_next_page = XEN_GREF_LIST_END; } else { to_copy = XEN_NUM_GREFS_PER_PAGE; page_dir->gref_dir_next_page = buf->grefs[i + 1]; |