From 17ef801d93fada1828f553e362b8029e19a6735d Mon Sep 17 00:00:00 2001 From: Nathan Lynch Date: Tue, 11 Feb 2014 22:28:42 +0000 Subject: [PATCH] arm64: vdso: clean up vdso_pagelist initialization Remove some unnecessary bits that were apparently carried over from another architecture's implementation: - No need to get_page() the vdso text/data - these are part of the kernel image. - No need for ClearPageReserved on the vdso text. - No need to vmap the first text page to check the ELF header - this can be done through &vdso_start. Also some minor cleanup: - Use kcalloc for vdso_pagelist array allocation. - Don't print on allocation failure, slab/slub will do that for us. Signed-off-by: Nathan Lynch Acked-by: Will Deacon Signed-off-by: Catalin Marinas (cherry picked from commit 16fb1a9bec6126162560f159df449e4781560807) Signed-off-by: Mark Brown --- arch/arm64/kernel/vdso.c | 42 ++++++++++++---------------------------- 1 file changed, 12 insertions(+), 30 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 0ea7a22bcdf2..10c27f5f6d23 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -103,49 +103,31 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) static int __init vdso_init(void) { - struct page *pg; - char *vbase; - int i, ret = 0; + int i; + + if (memcmp(&vdso_start, "\177ELF", 4)) { + pr_err("vDSO is not a valid ELF object!\n"); + return -EINVAL; + } vdso_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT; pr_info("vdso: %ld pages (%ld code, %ld data) at base %p\n", vdso_pages + 1, vdso_pages, 1L, &vdso_start); /* Allocate the vDSO pagelist, plus a page for the data. */ - vdso_pagelist = kzalloc(sizeof(struct page *) * (vdso_pages + 1), + vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *), GFP_KERNEL); - if (vdso_pagelist == NULL) { - pr_err("Failed to allocate vDSO pagelist!\n"); + if (vdso_pagelist == NULL) return -ENOMEM; - } /* Grab the vDSO code pages. */ - for (i = 0; i < vdso_pages; i++) { - pg = virt_to_page(&vdso_start + i*PAGE_SIZE); - ClearPageReserved(pg); - get_page(pg); - vdso_pagelist[i] = pg; - } - - /* Sanity check the shared object header. */ - vbase = vmap(vdso_pagelist, 1, 0, PAGE_KERNEL); - if (vbase == NULL) { - pr_err("Failed to map vDSO pagelist!\n"); - return -ENOMEM; - } else if (memcmp(vbase, "\177ELF", 4)) { - pr_err("vDSO is not a valid ELF object!\n"); - ret = -EINVAL; - goto unmap; - } + for (i = 0; i < vdso_pages; i++) + vdso_pagelist[i] = virt_to_page(&vdso_start + i * PAGE_SIZE); /* Grab the vDSO data page. */ - pg = virt_to_page(vdso_data); - get_page(pg); - vdso_pagelist[i] = pg; + vdso_pagelist[i] = virt_to_page(vdso_data); -unmap: - vunmap(vbase); - return ret; + return 0; } arch_initcall(vdso_init); -- 2.34.1