[PATCH] Coda updates [5/5]

Introduce a new kernel-userspace interface that uses 128-bit file
identifiers instead of the previously used 96-bit fileids. We also
replacing the coda_creds structure with only the fsuid.

This new API has been used by for a couple of months now, people had to
patch their kernels whenever they want to run a current Coda release.
A new Kconfig option is added to fall back on the old API for older Coda
clients and other userspace filesystems that might use our protocol.

fs/Kconfig

@@ -1562,6 +1562,20 @@ config CODA_FS
 	  whenever you want), say M here and read
 	  <file:Documentation/modules.txt>.  The module will be called coda.
 
+config CODA_FS_OLD_API
+	bool "Use 96-bit Coda file identifiers"
+	depends on CODA_FS
+	help
+	  A new kernel-userspace API had to be introduced for Coda v6.0
+	  to support larger 128-bit file identifiers as needed by the
+	  new realms implementation.
+
+	  However this new API is not backward compatible with older
+	  clients. If you really need to run the old Coda userspace
+	  cache manager then say Y.
+	  
+	  For most cases you probably want to say N.
+
 config INTERMEZZO_FS
 	tristate "InterMezzo file system support (replicating fs) (EXPERIMENTAL)"
 	depends on INET && EXPERIMENTAL

fs/coda/coda_linux.c

@@ -28,7 +28,11 @@ int coda_fake_statfs;
 char * coda_f2s(struct CodaFid *f)
 {
 	static char s[60];
+#ifdef CODA_FS_OLD_API
  	sprintf(s, "(%08x.%08x.%08x)", f->opaque[0], f->opaque[1], f->opaque[2]);
+#else
+ 	sprintf(s, "(%08x.%08x.%08x.%08x)", f->opaque[0], f->opaque[1], f->opaque[2], f->opaque[3]);
+#endif
 	return s;
 }
 

fs/coda/psdev.c

@@ -384,7 +384,13 @@ static int __init init_coda(void)
 {
 	int status;
 	int i;
-	printk(KERN_INFO "Coda Kernel/Venus communications, v5.3.15, coda@cs.cmu.edu\n");
+	printk(KERN_INFO "Coda Kernel/Venus communications, "
+#ifdef CODA_FS_OLD_API
+	       "v5.3.20"
+#else
+	       "v6.0.0"
+#endif
+	       ", coda@cs.cmu.edu\n");
 
 	status = coda_init_inodecache();
 	if (status)

fs/coda/upcall.c

@@ -55,9 +55,12 @@ static void *alloc_upcall(int opcode, int size)
         inp->ih.opcode = opcode;
 	inp->ih.pid = current->pid;
 	inp->ih.pgid = current->pgrp;
+#ifdef CODA_FS_OLD_API
 	memset(&inp->ih.cred, 0, sizeof(struct coda_cred));
 	inp->ih.cred.cr_fsuid = current->fsuid;
-
+#else
+	inp->ih.uid = current->fsuid;
+#endif
 	return (void*)inp;
 }
 
@@ -169,13 +172,19 @@ int venus_store(struct super_block *sb, struct CodaFid *fid, int flags,
         union inputArgs *inp;
         union outputArgs *outp;
         int insize, outsize, error;
+#ifdef CODA_FS_OLD_API
 	struct coda_cred cred = { 0, };
 	cred.cr_fsuid = uid;
+#endif
 	
 	insize = SIZE(store);
 	UPARG(CODA_STORE);
 	
+#ifdef CODA_FS_OLD_API
 	memcpy(&(inp->ih.cred), &cred, sizeof(cred));
+#else
+	inp->ih.uid = uid;
+#endif
 	
         inp->coda_store.VFid = *fid;
         inp->coda_store.flags = flags;
@@ -210,13 +219,19 @@ int venus_close(struct super_block *sb, struct CodaFid *fid, int flags,
 	union inputArgs *inp;
 	union outputArgs *outp;
 	int insize, outsize, error;
+#ifdef CODA_FS_OLD_API
 	struct coda_cred cred = { 0, };
 	cred.cr_fsuid = uid;
+#endif
 	
 	insize = SIZE(release);
 	UPARG(CODA_CLOSE);
 	
+#ifdef CODA_FS_OLD_API
 	memcpy(&(inp->ih.cred), &cred, sizeof(cred));
+#else
+	inp->ih.uid = uid;
+#endif
 	
         inp->coda_close.VFid = *fid;
         inp->coda_close.flags = flags;

include/linux/coda.h

@@ -59,7 +59,7 @@ Mellon the rights to redistribute these changes without encumbrance.
 #ifndef _CODA_HEADER_
 #define _CODA_HEADER_
 
-
+#include <linux/config.h>
 
 /* Catch new _KERNEL defn for NetBSD and DJGPP/__CYGWIN32__ */
 #if defined(__NetBSD__) || \
@@ -194,11 +194,17 @@ struct venus_dirent {
 
 #endif
 
+#ifndef _VUID_T_
+#define _VUID_T_
+typedef u_int32_t vuid_t;
+typedef u_int32_t vgid_t;
+#endif /*_VUID_T_ */
+
+#ifdef CODA_FS_OLD_API
 struct CodaFid {
 	u_int32_t opaque[3];
 };
 
-#ifdef __linux__
 static __inline__ ino_t  coda_f2i(struct CodaFid *fid)
 {
 	if ( ! fid ) 
@@ -208,26 +214,22 @@ static __inline__ ino_t  coda_f2i(struct CodaFid *fid)
 	else
 		return (fid->opaque[2] + (fid->opaque[1]<<10) + (fid->opaque[0]<<20));
 }
-	
-#else
-#define coda_f2i(fid)\
-	((fid) ? ((fid)->opaque[2] + ((fid)->opaque[1]<<10) + ((fid)->opaque[0]<<20)) : 0)
-#endif
-
-
-#ifndef _VUID_T_
-#define _VUID_T_
-typedef u_int32_t vuid_t;
-typedef u_int32_t vgid_t;
-#endif /*_VUID_T_ */
 
-#ifndef _CODACRED_T_
-#define _CODACRED_T_
 struct coda_cred {
     vuid_t cr_uid, cr_euid, cr_suid, cr_fsuid; /* Real, efftve, set, fs uid*/
     vgid_t cr_groupid, cr_egid, cr_sgid, cr_fsgid; /* same for groups */
 };
-#endif 
+
+#else /* not defined(CODA_FS_OLD_API) */
+
+struct CodaFid {
+	u_int32_t opaque[4];
+};
+
+#define coda_f2i(fid)\
+	(fid ? (fid->opaque[3] ^ (fid->opaque[2]<<10) ^ (fid->opaque[1]<<20) ^ fid->opaque[0]) : 0)
+
+#endif
 
 #ifndef _VENUS_VATTR_T_
 #define _VENUS_VATTR_T_
@@ -316,7 +318,11 @@ struct coda_statfs {
 #define CODA_KERNEL_VERSION 0 /* don't care about kernel version number */
 #define CODA_KERNEL_VERSION 1 /* The old venus 4.6 compatible interface */
 #endif
-#define CODA_KERNEL_VERSION 2 /* venus_lookup gets an extra parameter */
+#ifdef CODA_FS_OLD_API
+#define CODA_KERNEL_VERSION 2 /* venus_lookup got an extra parameter */
+#else
+#define CODA_KERNEL_VERSION 3 /* 128-bit file identifiers */
+#endif
 
 /*
  *        Venus <-> Coda  RPC arguments
@@ -324,10 +330,16 @@ struct coda_statfs {
 struct coda_in_hdr {
     u_int32_t opcode;
     u_int32_t unique;	    /* Keep multiple outstanding msgs distinct */
+#ifdef CODA_FS_OLD_API
     u_int16_t pid;	    /* Common to all */
     u_int16_t pgid;	    /* Common to all */
     u_int16_t sid;          /* Common to all */
     struct coda_cred cred;  /* Common to all */
+#else
+    pid_t pid;
+    pid_t pgid;
+    vuid_t uid;
+#endif
 };
 
 /* Really important that opcode and unique are 1st two fields! */
@@ -602,7 +614,11 @@ struct coda_vget_out {
 /* CODA_PURGEUSER is a venus->kernel call */
 struct coda_purgeuser_out {
     struct coda_out_hdr oh;
+#ifdef CODA_FS_OLD_API
     struct coda_cred cred;
+#else
+    vuid_t uid;
+#endif
 };
 
 /* coda_zapfile: */