NFS: directory trace messages

Reuse NFSDBG_DIRCACHE and NFSDBG_LOOKUPCACHE to provide additional
diagnostic messages that trace the operation of the NFS client's
directory behavior.  A few new messages are now generated when NFSDBG_VFS
is active, as well, to trace normal VFS activity.  This compromise
provides better trace debugging for those who use pre-built kernels,
without adding a lot of extra noise to the standard debug settings.

Test-plan:
Enable NFS trace debugging with flags 1, 2, or 4.  You should be able to
see different types of trace messages with each flag setting.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 66 insertions, 30 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 151b8dd0ac3b..609185a15c99 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -130,6 +130,9 @@ nfs_opendir(struct inode *inode, struct file *filp)
 {
         int res = 0;
 
+        dfprintk(VFS, "NFS: opendir(%s/%ld)\n",
+                        inode->i_sb->s_id, inode->i_ino);
+
         lock_kernel();
         /* Call generic open code in order to cache credentials */
         if (!res)
@@ -173,7 +176,9 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page)
         unsigned long   timestamp;
         int             error;
 
-        dfprintk(VFS, "NFS: nfs_readdir_filler() reading cookie %Lu into page %lu.\n", (long long)desc->entry->cookie, page->index);
+        dfprintk(DIRCACHE, "NFS: %s: reading cookie %Lu into page %lu\n",
+                        __FUNCTION__, (long long)desc->entry->cookie,
+                        page->index);
 
  again:
         timestamp = jiffies;
@@ -245,7 +250,8 @@ int find_dirent(nfs_readdir_descriptor_t *desc)
                         status;
 
         while((status = dir_decode(desc)) == 0) {
-                dfprintk(VFS, "NFS: found cookie %Lu\n", (unsigned long long)entry->cookie);
+                dfprintk(DIRCACHE, "NFS: %s: examining cookie %Lu\n",
+                                __FUNCTION__, (unsigned long long)entry->cookie);
                 if (entry->prev_cookie == *desc->dir_cookie)
                         break;
                 if (loop_count++ > 200) {
@@ -253,7 +259,6 @@ int find_dirent(nfs_readdir_descriptor_t *desc)
                         schedule();
                 }
         }
-        dfprintk(VFS, "NFS: find_dirent() returns %d\n", status);
         return status;
 }
 
@@ -277,7 +282,8 @@ int find_dirent_index(nfs_readdir_descriptor_t *desc)
                 if (status)
                         break;
 
-                dfprintk(VFS, "NFS: found cookie %Lu at index %Ld\n", (unsigned long long)entry->cookie, desc->current_index);
+                dfprintk(DIRCACHE, "NFS: found cookie %Lu at index %Ld\n",
+                                (unsigned long long)entry->cookie, desc->current_index);
 
                 if (desc->file->f_pos == desc->current_index) {
                         *desc->dir_cookie = entry->cookie;
@@ -289,7 +295,6 @@ int find_dirent_index(nfs_readdir_descriptor_t *desc)
                         schedule();
                 }
         }
-        dfprintk(VFS, "NFS: find_dirent_index() returns %d\n", status);
         return status;
 }
 
@@ -304,7 +309,9 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
         struct page     *page;
         int             status;
 
-        dfprintk(VFS, "NFS: find_dirent_page() searching directory page %ld\n", desc->page_index);
+        dfprintk(DIRCACHE, "NFS: %s: searching page %ld for target %Lu\n",
+                        __FUNCTION__, desc->page_index,
+                        (long long) *desc->dir_cookie);
 
         page = read_cache_page(inode->i_mapping, desc->page_index,
                                (filler_t *)nfs_readdir_filler, desc);
@@ -325,7 +332,7 @@ int find_dirent_page(nfs_readdir_descriptor_t *desc)
         if (status < 0)
                 dir_page_release(desc);
  out:
-        dfprintk(VFS, "NFS: find_dirent_page() returns %d\n", status);
+        dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status);
         return status;
  read_error:
         page_cache_release(page);
@@ -347,13 +354,15 @@ int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
 
         /* Always search-by-index from the beginning of the cache */
         if (*desc->dir_cookie == 0) {
-                dfprintk(VFS, "NFS: readdir_search_pagecache() searching for offset %Ld\n", (long long)desc->file->f_pos);
+                dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for offset %Ld\n",
+                                (long long)desc->file->f_pos);
                 desc->page_index = 0;
                 desc->entry->cookie = desc->entry->prev_cookie = 0;
                 desc->entry->eof = 0;
                 desc->current_index = 0;
         } else
-                dfprintk(VFS, "NFS: readdir_search_pagecache() searching for cookie %Lu\n", (unsigned long long)*desc->dir_cookie);
+                dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for cookie %Lu\n",
+                                (unsigned long long)*desc->dir_cookie);
 
         for (;;) {
                 res = find_dirent_page(desc);
@@ -366,7 +375,8 @@ int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
                         schedule();
                 }
         }
-        dfprintk(VFS, "NFS: readdir_search_pagecache() returned %d\n", res);
+
+        dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, res);
         return res;
 }
 
@@ -391,7 +401,8 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
         int             loop_count = 0,
                         res;
 
-        dfprintk(VFS, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n", (long long)entry->cookie);
+        dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n",
+                        (unsigned long long)entry->cookie);
 
         for(;;) {
                 unsigned d_type = DT_UNKNOWN;
@@ -428,7 +439,8 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
         dir_page_release(desc);
         if (dentry != NULL)
                 dput(dentry);
-        dfprintk(VFS, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n", (unsigned long long)*desc->dir_cookie, res);
+        dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
+                        (unsigned long long)*desc->dir_cookie, res);
         return res;
 }
 
@@ -454,7 +466,8 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
         struct page     *page = NULL;
         int             status;
 
-        dfprintk(VFS, "NFS: uncached_readdir() searching for cookie %Lu\n", (unsigned long long)*desc->dir_cookie);
+        dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
+                        (unsigned long long)*desc->dir_cookie);
 
         page = alloc_page(GFP_HIGHUSER);
         if (!page) {
@@ -486,7 +499,8 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
         desc->entry->cookie = desc->entry->prev_cookie = 0;
         desc->entry->eof = 0;
  out:
-        dfprintk(VFS, "NFS: uncached_readdir() returns %d\n", status);
+        dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
+                        __FUNCTION__, status);
         return status;
  out_release:
         dir_page_release(desc);
@@ -508,6 +522,9 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         struct nfs_fattr fattr;
         long            res;
 
+        dfprintk(VFS, "NFS: readdir(%s/%s) starting at cookie %Lu\n",
+                        dentry->d_parent->d_name.name, dentry->d_name.name,
+                        (long long)filp->f_pos);
         nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
 
         lock_kernel();
@@ -569,9 +586,12 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                 }
         }
         unlock_kernel();
-        if (res < 0)
-                return res;
-        return 0;
+        if (res > 0)
+                res = 0;
+        dfprintk(VFS, "NFS: readdir(%s/%s) returns %ld\n",
+                        dentry->d_parent->d_name.name, dentry->d_name.name,
+                        res);
+        return res;
 }
 
 loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
@@ -602,6 +622,10 @@ out:
  */
 int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync)
 {
+        dfprintk(VFS, "NFS: fsync_dir(%s/%s) datasync %d\n",
+                        dentry->d_parent->d_name.name, dentry->d_name.name,
+                        datasync);
+
         return 0;
 }
 
@@ -726,8 +750,9 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
         }
 
         if (is_bad_inode(inode)) {
-                dfprintk(VFS, "nfs_lookup_validate: %s/%s has dud inode\n",
-                        dentry->d_parent->d_name.name, dentry->d_name.name);
+                dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
+                                __FUNCTION__, dentry->d_parent->d_name.name,
+                                dentry->d_name.name);
                 goto out_bad;
         }
 
@@ -759,6 +784,9 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
  out_valid:
         unlock_kernel();
         dput(parent);
+        dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
+                        __FUNCTION__, dentry->d_parent->d_name.name,
+                        dentry->d_name.name);
         return 1;
 out_zap_parent:
         nfs_zap_caches(dir);
@@ -775,6 +803,9 @@ out_zap_parent:
         d_drop(dentry);
         unlock_kernel();
         dput(parent);
+        dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
+                        __FUNCTION__, dentry->d_parent->d_name.name,
+                        dentry->d_name.name);
         return 0;
 }
 
@@ -917,6 +948,9 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
         struct dentry *res = NULL;
         int error;
 
+        dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
+                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
+
         /* Check that we are indeed trying to open this file */
         if (!is_atomic_open(dir, nd))
                 goto no_open;
@@ -1124,8 +1158,8 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
         int error;
         int open_flags = 0;
 
-        dfprintk(VFS, "NFS: create(%s/%ld, %s\n", dir->i_sb->s_id, 
-                dir->i_ino, dentry->d_name.name);
+        dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
+                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
 
         attr.ia_mode = mode;
         attr.ia_valid = ATTR_MODE;
@@ -1158,8 +1192,8 @@ nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
         struct iattr attr;
         int status;
 
-        dfprintk(VFS, "NFS: mknod(%s/%ld, %s\n", dir->i_sb->s_id,
-                dir->i_ino, dentry->d_name.name);
+        dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
+                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
 
         if (!new_valid_dev(rdev))
                 return -EINVAL;
@@ -1191,8 +1225,8 @@ static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
         struct iattr attr;
         int error;
 
-        dfprintk(VFS, "NFS: mkdir(%s/%ld, %s\n", dir->i_sb->s_id,
-                dir->i_ino, dentry->d_name.name);
+        dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
+                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
 
         attr.ia_valid = ATTR_MODE;
         attr.ia_mode = mode | S_IFDIR;
@@ -1217,8 +1251,8 @@ static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
 {
         int error;
 
-        dfprintk(VFS, "NFS: rmdir(%s/%ld, %s\n", dir->i_sb->s_id,
-                dir->i_ino, dentry->d_name.name);
+        dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
+                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
 
         lock_kernel();
         nfs_begin_data_update(dir);
@@ -1274,8 +1308,8 @@ dentry->d_parent->d_name.name, dentry->d_name.name);
                 sillycounter++;
                 sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
 
-                dfprintk(VFS, "trying to rename %s to %s\n",
-                         dentry->d_name.name, silly);
+                dfprintk(VFS, "NFS: trying to rename %s to %s\n",
+                                dentry->d_name.name, silly);
                 
                 sdentry = lookup_one_len(silly, dentry->d_parent, slen);
                 /*
@@ -1687,13 +1721,15 @@ force_lookup:
                 res = PTR_ERR(cred);
         unlock_kernel();
 out:
+        dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
+                inode->i_sb->s_id, inode->i_ino, mask, res);
         return res;
 out_notsup:
         res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
         if (res == 0)
                 res = generic_permission(inode, mask, NULL);
         unlock_kernel();
-        return res;
+        goto out;
 }
 
 /*