[RFC PATCH v4 24/28] x86: Access the setup data through debugfs decrypted
From: Tom Lendacky <hidden>
Date: 2017-02-16 15:47:42
Also in:
kvm, linux-arch, linux-iommu, linux-mm, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Use memremap() to map the setup data. This simplifies the code and will make the appropriate decision as to whether a RAM remapping can be done or if a fallback to ioremap_cache() is needed (which includes checking PageHighMem). Signed-off-by: Tom Lendacky <redacted> --- arch/x86/kernel/kdebugfs.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-)
diff --git a/arch/x86/kernel/kdebugfs.c b/arch/x86/kernel/kdebugfs.c
index bdb83e4..c3d354d 100644
--- a/arch/x86/kernel/kdebugfs.c
+++ b/arch/x86/kernel/kdebugfs.c@@ -48,17 +48,13 @@ static ssize_t setup_data_read(struct file *file, char __user *user_buf, pa = node->paddr + sizeof(struct setup_data) + pos; pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT); - if (PageHighMem(pg)) { - p = ioremap_cache(pa, count); - if (!p) - return -ENXIO; - } else - p = __va(pa); + p = memremap(pa, count, MEMREMAP_WB); + if (!p) + return -ENXIO; remain = copy_to_user(user_buf, p, count); - if (PageHighMem(pg)) - iounmap(p); + memunmap(p); if (remain) return -EFAULT;
@@ -127,15 +123,12 @@ static int __init create_setup_data_nodes(struct dentry *parent) } pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT); - if (PageHighMem(pg)) { - data = ioremap_cache(pa_data, sizeof(*data)); - if (!data) { - kfree(node); - error = -ENXIO; - goto err_dir; - } - } else - data = __va(pa_data); + data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); + if (!data) { + kfree(node); + error = -ENXIO; + goto err_dir; + } node->paddr = pa_data; node->type = data->type;
@@ -143,8 +136,7 @@ static int __init create_setup_data_nodes(struct dentry *parent) error = create_setup_data_node(d, no, node); pa_data = data->next; - if (PageHighMem(pg)) - iounmap(data); + memunmap(data); if (error) goto err_dir; no++;