It is not possible to register buffers allocated with vmalloc. Use iov_iter and associated helper functions to manage the page registration for all type of memories.
Suggested-by: Christoph Hellwig hch@infradead.org Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com ---
Update from V2 to V3: - break lines longer than 80 columns.
Update from V1 to V2: - replace ITER_SOURCE by ITER_DEST flag in tee_shm_register_user_buf(), - replace IS_ERR_OR NULL(shm) by IS_ERR(shm) in tee_shm_register_user_buf().
V1: The support of buffer registration allocated with vmalloc is no more available since c83900393aa1 ("tee: Remove vmalloc page support").
This patch is an alternative to a revert and resulted from a discussion with Christopher Hellwig [1].
This patch has been tested using xtest tool in optee qemu environment [2] and using the series related to the remoteproc tee that should be proposed soon [3].
References: [1] https://lore.kernel.org/linux-arm-kernel/18a8528d-7d9d-6ed0-0045-5ee47dd39fb... [2] https://optee.readthedocs.io/en/latest/building/devices/qemu.html#build-inst... [3] https://lore.kernel.org/linux-arm-kernel/18a8528d-7d9d-6ed0-0045-5ee47dd39fb... --- drivers/tee/tee_shm.c | 77 ++++++++++++++++++++++++------------------- 1 file changed, 43 insertions(+), 34 deletions(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 673cf0359494..fe0a205be7ef 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -22,23 +22,16 @@ static void shm_put_kernel_pages(struct page **pages, size_t page_count) put_page(pages[n]); }
-static int shm_get_kernel_pages(unsigned long start, size_t page_count, - struct page **pages) +static void shm_get_kernel_pages(struct page **pages, size_t page_count) { - struct page *page; size_t n;
- if (WARN_ON_ONCE(is_vmalloc_addr((void *)start) || - is_kmap_addr((void *)start))) - return -EINVAL; - - page = virt_to_page((void *)start); - for (n = 0; n < page_count; n++) { - pages[n] = page + n; + /* + * iov_iter_extract_kvec_pages does not get reference on the pages, + * get a pin on them. + */ + for (n = 0; n < page_count; n++) get_page(pages[n]); - } - - return page_count; }
static void release_registered_pages(struct tee_shm *shm) @@ -214,13 +207,13 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size) EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
static struct tee_shm * -register_shm_helper(struct tee_context *ctx, unsigned long addr, - size_t length, u32 flags, int id) +register_shm_helper(struct tee_context *ctx, struct iov_iter *iter, u32 flags, + int id) { struct tee_device *teedev = ctx->teedev; struct tee_shm *shm; - unsigned long start; - size_t num_pages; + unsigned long start, addr; + size_t num_pages, length, len, off; void *ret; int rc;
@@ -245,31 +238,32 @@ register_shm_helper(struct tee_context *ctx, unsigned long addr, shm->flags = flags; shm->ctx = ctx; shm->id = id; - addr = untagged_addr(addr); + addr = (unsigned long)iter_iov_addr(iter); + length = iter_iov_len(iter); start = rounddown(addr, PAGE_SIZE); - shm->offset = addr - start; - shm->size = length; - num_pages = (roundup(addr + length, PAGE_SIZE) - start) / PAGE_SIZE; + num_pages = iov_iter_npages(iter, INT_MAX); + if (!num_pages) { + ret = ERR_PTR(-ENOMEM); + goto err_ctx_put; + } + shm->pages = kcalloc(num_pages, sizeof(*shm->pages), GFP_KERNEL); if (!shm->pages) { ret = ERR_PTR(-ENOMEM); goto err_free_shm; }
- if (flags & TEE_SHM_USER_MAPPED) - rc = pin_user_pages_fast(start, num_pages, FOLL_WRITE, - shm->pages); - else - rc = shm_get_kernel_pages(start, num_pages, shm->pages); - if (rc > 0) - shm->num_pages = rc; - if (rc != num_pages) { - if (rc >= 0) - rc = -ENOMEM; - ret = ERR_PTR(rc); + len = iov_iter_extract_pages(iter, &shm->pages, LONG_MAX, num_pages, 0, + &off); + if (len != length) { + ret = len ? ERR_PTR(len) : ERR_PTR(-ENOMEM); goto err_put_shm_pages; }
+ shm->offset = off; + shm->size = len; + shm->num_pages = num_pages; + rc = teedev->desc->ops->shm_register(ctx, shm, shm->pages, shm->num_pages, start); if (rc) { @@ -307,6 +301,8 @@ struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx, u32 flags = TEE_SHM_USER_MAPPED | TEE_SHM_DYNAMIC; struct tee_device *teedev = ctx->teedev; struct tee_shm *shm; + struct iovec iov; + struct iov_iter iter; void *ret; int id;
@@ -319,7 +315,10 @@ struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx, if (id < 0) return ERR_PTR(id);
- shm = register_shm_helper(ctx, addr, length, flags, id); + iov.iov_base = (void __user *)addr; + iov.iov_len = length; + iov_iter_init(&iter, ITER_DEST, &iov, 1, length); + shm = register_shm_helper(ctx, &iter, flags, id); if (IS_ERR(shm)) { mutex_lock(&teedev->mutex); idr_remove(&teedev->idr, id); @@ -351,9 +350,19 @@ struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx, struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx, void *addr, size_t length) { + struct tee_shm *shm; u32 flags = TEE_SHM_DYNAMIC; + struct kvec kvec; + struct iov_iter iter;
- return register_shm_helper(ctx, (unsigned long)addr, length, flags, -1); + kvec.iov_base = addr; + kvec.iov_len = length; + iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, length); + shm = register_shm_helper(ctx, &iter, flags, -1); + if (!IS_ERR(shm)) + shm_get_kernel_pages(shm->pages, shm->num_pages); + + return shm; } EXPORT_SYMBOL_GPL(tee_shm_register_kernel_buf);