summaryrefslogtreecommitdiff
path: root/drivers/s390/char
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2015-10-12 11:51:54 +0300
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2015-11-27 11:24:13 +0300
commit019d6bec6d2842729c477f433b2330e9f52c0f1a (patch)
treef45beeb6d67b680441ab3e5c575d7d4fe08340f8 /drivers/s390/char
parentdf9694c7975ff9976368eb381388c61f65352aef (diff)
downloadlinux-019d6bec6d2842729c477f433b2330e9f52c0f1a.tar.xz
s390/zcore: simplify memcpy_hsa
Replace the three part copy logic int memcpy_hsa with a single loop around sclp_sdias_copy with appropriate offset and size calculations, and inline memcpy_hsa into memcpy_hsa_user and memcpy_hsa_kernel. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/char')
-rw-r--r--drivers/s390/char/zcore.c101
1 files changed, 33 insertions, 68 deletions
diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c
index 4fa455787a77..7d94c696c38b 100644
--- a/drivers/s390/char/zcore.c
+++ b/drivers/s390/char/zcore.c
@@ -34,8 +34,6 @@
#define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x)
-#define TO_USER 1
-#define TO_KERNEL 0
#define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */
enum arch_id {
@@ -56,89 +54,39 @@ static struct dentry *zcore_reipl_file;
static struct dentry *zcore_hsa_file;
static struct ipl_parameter_block *ipl_block;
+static char hsa_buf[PAGE_SIZE] __aligned(PAGE_SIZE);
+
/*
- * Copy memory from HSA to kernel or user memory (not reentrant):
+ * Copy memory from HSA to user memory (not reentrant):
*
- * @dest: Kernel or user buffer where memory should be copied to
+ * @dest: User buffer where memory should be copied to
* @src: Start address within HSA where data should be copied
* @count: Size of buffer, which should be copied
- * @mode: Either TO_KERNEL or TO_USER
*/
-static int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode)
+int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count)
{
- int offs, blk_num;
- static char buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
+ unsigned long offset, bytes;
if (!hsa_available)
return -ENODATA;
- if (count == 0)
- return 0;
-
- /* copy first block */
- offs = 0;
- if ((src % PAGE_SIZE) != 0) {
- blk_num = src / PAGE_SIZE + 2;
- if (sclp_sdias_copy(buf, blk_num, 1)) {
- TRACE("sclp_sdias_copy() failed\n");
- return -EIO;
- }
- offs = min((PAGE_SIZE - (src % PAGE_SIZE)), count);
- if (mode == TO_USER) {
- if (copy_to_user((__force __user void*) dest,
- buf + (src % PAGE_SIZE), offs))
- return -EFAULT;
- } else
- memcpy(dest, buf + (src % PAGE_SIZE), offs);
- }
- if (offs == count)
- goto out;
- /* copy middle */
- for (; (offs + PAGE_SIZE) <= count; offs += PAGE_SIZE) {
- blk_num = (src + offs) / PAGE_SIZE + 2;
- if (sclp_sdias_copy(buf, blk_num, 1)) {
+ while (count) {
+ if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) {
TRACE("sclp_sdias_copy() failed\n");
return -EIO;
}
- if (mode == TO_USER) {
- if (copy_to_user((__force __user void*) dest + offs,
- buf, PAGE_SIZE))
- return -EFAULT;
- } else
- memcpy(dest + offs, buf, PAGE_SIZE);
- }
- if (offs == count)
- goto out;
-
- /* copy last block */
- blk_num = (src + offs) / PAGE_SIZE + 2;
- if (sclp_sdias_copy(buf, blk_num, 1)) {
- TRACE("sclp_sdias_copy() failed\n");
- return -EIO;
- }
- if (mode == TO_USER) {
- if (copy_to_user((__force __user void*) dest + offs, buf,
- count - offs))
+ offset = src % PAGE_SIZE;
+ bytes = min(PAGE_SIZE - offset, count);
+ if (copy_to_user(dest, hsa_buf + offset, bytes))
return -EFAULT;
- } else
- memcpy(dest + offs, buf, count - offs);
-out:
+ src += bytes;
+ dest += bytes;
+ count -= bytes;
+ }
return 0;
}
/*
- * Copy memory from HSA to user memory (not reentrant):
- *
- * @dest: Kernel or user buffer where memory should be copied to
- * @src: Start address within HSA where data should be copied
- * @count: Size of buffer, which should be copied
- */
-int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count)
-{
- return memcpy_hsa((void __force *) dest, src, count, TO_USER);
-}
-
-/*
* Copy memory from HSA to kernel memory (not reentrant):
*
* @dest: Kernel or user buffer where memory should be copied to
@@ -147,7 +95,24 @@ int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count)
*/
int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count)
{
- return memcpy_hsa(dest, src, count, TO_KERNEL);
+ unsigned long offset, bytes;
+
+ if (!hsa_available)
+ return -ENODATA;
+
+ while (count) {
+ if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) {
+ TRACE("sclp_sdias_copy() failed\n");
+ return -EIO;
+ }
+ offset = src % PAGE_SIZE;
+ bytes = min(PAGE_SIZE - offset, count);
+ memcpy(dest, hsa_buf + offset, bytes);
+ src += bytes;
+ dest += bytes;
+ count -= bytes;
+ }
+ return 0;
}
static int __init init_cpu_info(void)