[RFC PATCH v4 25/28] x86: Access the setup data through sysfs decrypted

Tom Lendacky
2017-02-16T15:47:38Z

Use memremap() to map the setup data. This will make the appropriate
decision as to whether a RAM remapping can be done or if a fallback to
ioremap_cache() is needed (similar to the setup data debugfs support).

Signed-off-by: Tom Lendacky <thomas.lendacky-5C7GfCeVMHo@public.gmane.org>
---
arch/x86/kernel/ksysfs.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/ksysfs.c b/arch/x86/kernel/ksysfs.c
index 4afc67f..d653b3e 100644
--- a/arch/x86/kernel/ksysfs.c
+++ b/arch/x86/kernel/ksysfs.c
@@ -16,6 +16,7 @@
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/mm.h>
+#include <linux/io.h>

#include <asm/io.h>
#include <asm/setup.h>
@@ -79,12 +80,12 @@ static int get_setup_data_paddr(int nr, u64 *paddr)
*paddr = pa_data;
return 0;
}
- data = ioremap_cache(pa_data, sizeof(*data));
+ data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
if (!data)
return -ENOMEM;

pa_data = data->next;
- iounmap(data);
+ memunmap(data);
i++;
}
return -EINVAL;
@@ -97,17 +98,17 @@ static int __init get_setup_data_size(int nr, size_t *size)
u64 pa_data = boot_params.hdr.setup_data;

while (pa_data) {
- data = ioremap_cache(pa_data, sizeof(*data));
+ data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
if (!data)
return -ENOMEM;
if (nr == i) {
*size = data->len;
- iounmap(data);
+ memunmap(data);
return 0;
}

pa_data = data->next;
- iounmap(data);
+ memunmap(data);
i++;
}
return -EINVAL;
@@ -127,12 +128,12 @@ static ssize_t type_show(struct kobject *kobj,
ret = get_setup_data_paddr(nr, &paddr);
if (ret)
return ret;
- data = ioremap_cache(paddr, sizeof(*data));
+ data = memremap(paddr, sizeof(*data), MEMREMAP_WB);
if (!data)
return -ENOMEM;

ret = sprintf(buf, "0x%x\n", data->type);
- iounmap(data);
+ memunmap(data);
return ret;
}

@@ -154,7 +155,7 @@ static ssize_t setup_data_data_read(struct file *fp,
ret = get_setup_data_paddr(nr, &paddr);
if (ret)
return ret;
- data = ioremap_cache(paddr, sizeof(*data));
+ data = memremap(paddr, sizeof(*data), MEMREMAP_WB);
if (!data)
return -ENOMEM;

@@ -170,15 +171,15 @@ static ssize_t setup_data_data_read(struct file *fp,
goto out;

ret = count;
- p = ioremap_cache(paddr + sizeof(*data), data->len);
+ p = memremap(paddr + sizeof(*data), data->len, MEMREMAP_WB);
if (!p) {
ret = -ENOMEM;
goto out;
}
memcpy(buf, p + off, count);
- iounmap(p);
+ memunmap(p);
out:
- iounmap(data);
+ memunmap(data);
return ret;
}

@@ -250,13 +251,13 @@ static int __init get_setup_data_total_num(u64 pa_data, int *nr)
*nr = 0;
while (pa_data) {
*nr += 1;
- data = ioremap_cache(pa_data, sizeof(*data));
+ data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
if (!data) {
ret = -ENOMEM;
goto out;
}
pa_data = data->next;
- iounmap(data);
+ memunmap(data);
}