From: Marc Dionne <marc.c.dionne@gmail.com>
Date: Tue, 23 Nov 2010 22:50:25 +0000 (-0500)
Subject: Cache bypass: Remove AFS_KMAP_ATOMIC
X-Git-Tag: openafs-devel-1_7_1~1204
X-Git-Url: https://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=1de6d5bb0122d00c398202451bf88042ea08aa3e;hp=b9a0be5b07e750401d9659678d922a729a55ed48

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
--- 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