Coda: replace BKL with mutex

Replace the BKL with a mutex to protect the venus_comm structure which
binds the mountpoint with the character device and holds the upcall
queues.

Signed-off-by: Yoshihisa Abe <yoshiabe@cs.cmu.edu>
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 40 insertions, 31 deletions

diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c
index 4c258cb5266d..c3563cab9758 100644
--- a/fs/coda/upcall.c
+++ b/fs/coda/upcall.c
@@ -27,7 +27,7 @@
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include <asm/uaccess.h>
 #include <linux/vmalloc.h>
 #include <linux/vfs.h>
@@ -607,7 +607,8 @@ static void coda_unblock_signals(sigset_t *old)
                                  (r)->uc_opcode != CODA_RELEASE) || \
                                 (r)->uc_flags & CODA_REQ_READ))
 
-static inline void coda_waitfor_upcall(struct upc_req *req)
+static inline void coda_waitfor_upcall(struct venus_comm *vcp,
+                                       struct upc_req *req)
 {
         DECLARE_WAITQUEUE(wait, current);
         unsigned long timeout = jiffies + coda_timeout * HZ;
@@ -640,10 +641,12 @@ static inline void coda_waitfor_upcall(struct upc_req *req)
                         break;
                 }
 
+                mutex_unlock(&vcp->vc_mutex);
                 if (blocked)
                         schedule_timeout(HZ);
                 else
                         schedule();
+                mutex_lock(&vcp->vc_mutex);
         }
         if (blocked)
                 coda_unblock_signals(&old);
@@ -671,7 +674,7 @@ static int coda_upcall(struct venus_comm *vcp,
         struct upc_req *req = NULL, *sig_req;
         int error;
 
-        lock_kernel();
+        mutex_lock(&vcp->vc_mutex);
 
         if (!vcp->vc_inuse) {
                 printk(KERN_NOTICE "coda: Venus dead, not sending upcall\n");
@@ -711,7 +714,7 @@ static int coda_upcall(struct venus_comm *vcp,
          * ENODEV.  */
 
         /* Go to sleep.  Wake up on signals only after the timeout. */
-        coda_waitfor_upcall(req);
+        coda_waitfor_upcall(vcp, req);
 
         /* Op went through, interrupt or not... */
         if (req->uc_flags & CODA_REQ_WRITE) {
@@ -765,7 +768,7 @@ static int coda_upcall(struct venus_comm *vcp,
 
 exit:
         kfree(req);
-        unlock_kernel();
+        mutex_unlock(&vcp->vc_mutex);
         return error;
 }
 
@@ -806,11 +809,11 @@ exit:
 int coda_downcall(struct venus_comm *vcp, int opcode, union outputArgs *out)
 {
         struct inode *inode = NULL;
-        struct CodaFid *fid, *newfid;
+        struct CodaFid *fid = NULL, *newfid;
         struct super_block *sb;
 
         /* Handle invalidation requests. */
-        lock_kernel();
+        mutex_lock(&vcp->vc_mutex);
         sb = vcp->vc_sb;
         if (!sb || !sb->s_root)
                 goto unlock_out;
@@ -829,47 +832,53 @@ int coda_downcall(struct venus_comm *vcp, int opcode, union outputArgs *out)
 
         case CODA_ZAPDIR:
                 fid = &out->coda_zapdir.CodaFid;
-                inode = coda_fid_to_inode(fid, sb);
-                if (inode) {
-                        coda_flag_inode_children(inode, C_PURGE);
-                        coda_flag_inode(inode, C_VATTR);
-                }
                 break;
 
         case CODA_ZAPFILE:
                 fid = &out->coda_zapfile.CodaFid;
-                inode = coda_fid_to_inode(fid, sb);
-                if (inode)
-                        coda_flag_inode(inode, C_VATTR);
                 break;
 
         case CODA_PURGEFID:
                 fid = &out->coda_purgefid.CodaFid;
-                inode = coda_fid_to_inode(fid, sb);
-                if (inode) {
-                        coda_flag_inode_children(inode, C_PURGE);
-
-                        /* catch the dentries later if some are still busy */
-                        coda_flag_inode(inode, C_PURGE);
-                        d_prune_aliases(inode);
-
-                }
                 break;
 
         case CODA_REPLACE:
                 fid = &out->coda_replace.OldFid;
-                newfid = &out->coda_replace.NewFid;
-                inode = coda_fid_to_inode(fid, sb);
-                if (inode)
-                        coda_replace_fid(inode, fid, newfid);
                 break;
         }
+        if (fid)
+                inode = coda_fid_to_inode(fid, sb);
 
 unlock_out:
-        unlock_kernel();
+        mutex_unlock(&vcp->vc_mutex);
+
+        if (!inode)
+                return 0;
+
+        switch (opcode) {
+        case CODA_ZAPDIR:
+                coda_flag_inode_children(inode, C_PURGE);
+                coda_flag_inode(inode, C_VATTR);
+                break;
+
+        case CODA_ZAPFILE:
+                coda_flag_inode(inode, C_VATTR);
+                break;
+
+        case CODA_PURGEFID:
+                coda_flag_inode_children(inode, C_PURGE);
 
-        if (inode)
-                iput(inode);
+                /* catch the dentries later if some are still busy */
+                coda_flag_inode(inode, C_PURGE);
+                d_prune_aliases(inode);
+                break;
+
+        case CODA_REPLACE:
+                newfid = &out->coda_replace.NewFid;
+                coda_replace_fid(inode, fid, newfid);
+                break;
+        }
+        iput(inode);
         return 0;
 }