Cache bypass: Remove AFS_KMAP_ATOMIC

Since AFS_KMAP_ATOMIC is defined unconditionally, remove the ifdefs
and the code for the !AFS_KMAP_ATOMIC case.  We probably don't want
to support this feature on a kernel old enough not to have kmap_atomic.
This should exist on all 2.6 and even 2.4 linux kernels.

This simplifies the code for maintenance and later changes.

Change-Id: I5d111d65066990123db917ac105a5a14db3b305f
Reviewed-on: http://gerrit.openafs.org/3372
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>

diff --git a/src/afs/afs_bypasscache.c b/src/afs/afs_bypasscache.c
index a6e1c18..8d7e601 100644 (file)
--- a/src/afs/afs_bypasscache.c
+++ b/src/afs/afs_bypasscache.c
@@ -79,7 +79,6 @@
 #define LockPage(pp) lock_page(pp)
 #define UnlockPage(pp) unlock_page(pp)
 #endif
-#define AFS_KMAP_ATOMIC
 
 #ifndef afs_min
 #define afs_min(A,B) ((A)<(B)) ? (A) : (B)
@@ -322,11 +321,7 @@ afs_NoCacheFetchProc(struct rx_call *acall,
     struct iovec *ciov;
     struct page *pp;
     char *address;
-#ifdef AFS_KMAP_ATOMIC
     char *page_buffer = osi_Alloc(PAGE_SIZE);
-#else
-    char *page_buffer = NULL;
-#endif
 
     ciov = auio->uio_iov;
     pp = (struct page*) ciov->iov_base;
@@ -383,21 +378,7 @@ afs_NoCacheFetchProc(struct rx_call *acall,
            clen = ciov->iov_len - iovoff;
            tlen = afs_min(length, clen);
 #ifdef AFS_LINUX24_ENV
-#ifndef AFS_KMAP_ATOMIC
-           if(pp)
-               address = kmap(pp);
-           else {
-               /* rx doesn't provide an interface to simply advance
-                  or consume n bytes.  for now, allocate a PAGE_SIZE
-                  region of memory to receive bytes in the case that
-                  there were holes in readpages */
-               if(page_buffer == NULL)
-                   page_buffer = osi_Alloc(PAGE_SIZE);
-                   address = page_buffer;
-               }
-#else
            address = page_buffer;
-#endif
 #else
 #ifndef UKERNEL
 #error AFS_CACHE_BYPASS not implemented on this platform
@@ -426,13 +407,11 @@ afs_NoCacheFetchProc(struct rx_call *acall,
                address += code;
            } else {
 #ifdef AFS_LINUX24_ENV
-#ifdef AFS_KMAP_ATOMIC
                if(pp) {
                    address = kmap_atomic(pp, KM_USER0);
                    memcpy(address, page_buffer, PAGE_SIZE);
                    kunmap_atomic(address, KM_USER0);
                }
-#endif
 #else
 #ifndef UKERNEL
 #error AFS_CACHE_BYPASS not implemented on this platform
@@ -449,9 +428,6 @@ afs_NoCacheFetchProc(struct rx_call *acall,
                     else
                         afs_warn("afs_NoCacheFetchProc: page not locked at iovno %d!\n", iovno);
                     put_page(pp); /* decrement refcount */
-#ifndef AFS_KMAP_ATOMIC
-                    kunmap(pp);
-#endif
 #else
 #ifndef UKERNEL
 #error AFS_CACHE_BYPASS not implemented on this platform