1 files changed, 98 insertions, 113 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 8bdbc818164c..f050dba920cb 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -77,6 +77,41 @@ static void cifs_set_ops(struct inode *inode, const bool is_dfs_referral)
         }
 }
 
+/* check inode attributes against fattr. If they don't match, tag the
+ * inode for cache invalidation
+ */
+static void
+cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
+{
+        struct cifsInodeInfo *cifs_i = CIFS_I(inode);
+
+        cFYI(1, ("%s: revalidating inode %llu", __func__, cifs_i->uniqueid));
+
+        if (inode->i_state & I_NEW) {
+                cFYI(1, ("%s: inode %llu is new", __func__, cifs_i->uniqueid));
+                return;
+        }
+
+        /* don't bother with revalidation if we have an oplock */
+        if (cifs_i->clientCanCacheRead) {
+                cFYI(1, ("%s: inode %llu is oplocked", __func__,
+                         cifs_i->uniqueid));
+                return;
+        }
+
+         /* revalidate if mtime or size have changed */
+        if (timespec_equal(&inode->i_mtime, &fattr->cf_mtime) &&
+            cifs_i->server_eof == fattr->cf_eof) {
+                cFYI(1, ("%s: inode %llu is unchanged", __func__,
+                         cifs_i->uniqueid));
+                return;
+        }
+
+        cFYI(1, ("%s: invalidating inode %llu mapping", __func__,
+                 cifs_i->uniqueid));
+        cifs_i->invalid_mapping = true;
+}
+
 /* populate an inode with info from a cifs_fattr struct */
 void
 cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
@@ -85,6 +120,8 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
         unsigned long oldtime = cifs_i->time;
 
+        cifs_revalidate_cache(inode, fattr);
+
         inode->i_atime = fattr->cf_atime;
         inode->i_mtime = fattr->cf_mtime;
         inode->i_ctime = fattr->cf_ctime;
@@ -1389,135 +1426,83 @@ cifs_rename_exit:
         return rc;
 }
 
-int cifs_revalidate(struct dentry *direntry)
+static bool
+cifs_inode_needs_reval(struct inode *inode)
 {
-        int xid;
-        int rc = 0, wbrc = 0;
-        char *full_path;
-        struct cifs_sb_info *cifs_sb;
-        struct cifsInodeInfo *cifsInode;
-        loff_t local_size;
-        struct timespec local_mtime;
-        bool invalidate_inode = false;
+        struct cifsInodeInfo *cifs_i = CIFS_I(inode);
 
-        if (direntry->d_inode == NULL)
-                return -ENOENT;
+        if (cifs_i->clientCanCacheRead)
+                return false;
 
-        cifsInode = CIFS_I(direntry->d_inode);
+        if (!lookupCacheEnabled)
+                return true;
 
-        if (cifsInode == NULL)
-                return -ENOENT;
+        if (cifs_i->time == 0)
+                return true;
 
-        /* no sense revalidating inode info on file that no one can write */
-        if (CIFS_I(direntry->d_inode)->clientCanCacheRead)
-                return rc;
+        /* FIXME: the actimeo should be tunable */
+        if (time_after_eq(jiffies, cifs_i->time + HZ))
+                return true;
+
+        return false;
+}
+
+/* check invalid_mapping flag and zap the cache if it's set */
+static void
+cifs_invalidate_mapping(struct inode *inode)
+{
+        int rc;
+        struct cifsInodeInfo *cifs_i = CIFS_I(inode);
+
+        cifs_i->invalid_mapping = false;
+
+        /* write back any cached data */
+        if (inode->i_mapping && inode->i_mapping->nrpages != 0) {
+                rc = filemap_write_and_wait(inode->i_mapping);
+                if (rc)
+                        cifs_i->write_behind_rc = rc;
+        }
+        invalidate_remote_inode(inode);
+}
+
+/* revalidate a dentry's inode attributes */
+int cifs_revalidate_dentry(struct dentry *dentry)
+{
+        int xid;
+        int rc = 0;
+        char *full_path = NULL;
+        struct inode *inode = dentry->d_inode;
+        struct super_block *sb = dentry->d_sb;
+
+        if (inode == NULL)
+                return -ENOENT;
 
         xid = GetXid();
 
-        cifs_sb = CIFS_SB(direntry->d_sb);
+        if (!cifs_inode_needs_reval(inode))
+                goto check_inval;
 
         /* can not safely grab the rename sem here if rename calls revalidate
            since that would deadlock */
-        full_path = build_path_from_dentry(direntry);
+        full_path = build_path_from_dentry(dentry);
         if (full_path == NULL) {
                 rc = -ENOMEM;
-                FreeXid(xid);
-                return rc;
+                goto check_inval;
         }
-        cFYI(1, ("Revalidate: %s inode 0x%p count %d dentry: 0x%p d_time %ld "
-                 "jiffies %ld", full_path, direntry->d_inode,
-                 direntry->d_inode->i_count.counter, direntry,
-                 direntry->d_time, jiffies));
-
-        if (cifsInode->time == 0) {
-                /* was set to zero previously to force revalidate */
-        } else if (time_before(jiffies, cifsInode->time + HZ) &&
-                   lookupCacheEnabled) {
-                if ((S_ISREG(direntry->d_inode->i_mode) == 0) ||
-                    (direntry->d_inode->i_nlink == 1)) {
-                        kfree(full_path);
-                        FreeXid(xid);
-                        return rc;
-                } else {
-                        cFYI(1, ("Have to revalidate file due to hardlinks"));
-                }
-        }
-
-        /* save mtime and size */
-        local_mtime = direntry->d_inode->i_mtime;
-        local_size = direntry->d_inode->i_size;
 
-        if (cifs_sb->tcon->unix_ext) {
-                rc = cifs_get_inode_info_unix(&direntry->d_inode, full_path,
-                                              direntry->d_sb, xid);
-                if (rc) {
-                        cFYI(1, ("error on getting revalidate info %d", rc));
-/*                      if (rc != -ENOENT)
-                                rc = 0; */      /* BB should we cache info on
-                                                   certain errors? */
-                }
-        } else {
-                rc = cifs_get_inode_info(&direntry->d_inode, full_path, NULL,
-                                         direntry->d_sb, xid, NULL);
-                if (rc) {
-                        cFYI(1, ("error on getting revalidate info %d", rc));
-/*                      if (rc != -ENOENT)
-                                rc = 0; */      /* BB should we cache info on
-                                                   certain errors? */
-                }
-        }
-        /* should we remap certain errors, access denied?, to zero */
-
-        /* if not oplocked, we invalidate inode pages if mtime or file size
-           had changed on server */
+        cFYI(1, ("Revalidate: %s inode 0x%p count %d dentry: 0x%p d_time %ld "
+                 "jiffies %ld", full_path, inode, inode->i_count.counter,
+                 dentry, dentry->d_time, jiffies));
 
-        if (timespec_equal(&local_mtime, &direntry->d_inode->i_mtime) &&
-            (local_size == direntry->d_inode->i_size)) {
-                cFYI(1, ("cifs_revalidate - inode unchanged"));
-        } else {
-                /* file may have changed on server */
-                if (cifsInode->clientCanCacheRead) {
-                        /* no need to invalidate inode pages since we were the
-                           only ones who could have modified the file and the
-                           server copy is staler than ours */
-                } else {
-                        invalidate_inode = true;
-                }
-        }
+        if (CIFS_SB(sb)->tcon->unix_ext)
+                rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);
+        else
+                rc = cifs_get_inode_info(&inode, full_path, NULL, sb,
+                                         xid, NULL);
 
-        /* can not grab this sem since kernel filesys locking documentation
-           indicates i_mutex may be taken by the kernel on lookup and rename
-           which could deadlock if we grab the i_mutex here as well */
-/*      mutex_lock(&direntry->d_inode->i_mutex);*/
-        /* need to write out dirty pages here  */
-        if (direntry->d_inode->i_mapping) {
-                /* do we need to lock inode until after invalidate completes
-                   below? */
-                wbrc = filemap_fdatawrite(direntry->d_inode->i_mapping);
-                if (wbrc)
-                        CIFS_I(direntry->d_inode)->write_behind_rc = wbrc;
-        }
-        if (invalidate_inode) {
-        /* shrink_dcache not necessary now that cifs dentry ops
-        are exported for negative dentries */
-/*              if (S_ISDIR(direntry->d_inode->i_mode))
-                        shrink_dcache_parent(direntry); */
-                if (S_ISREG(direntry->d_inode->i_mode)) {
-                        if (direntry->d_inode->i_mapping) {
-                                wbrc = filemap_fdatawait(direntry->d_inode->i_mapping);
-                                if (wbrc)
-                                        CIFS_I(direntry->d_inode)->write_behind_rc = wbrc;
-                        }
-                        /* may eventually have to do this for open files too */
-                        if (list_empty(&(cifsInode->openFileList))) {
-                                /* changed on server - flush read ahead pages */
-                                cFYI(1, ("Invalidating read ahead data on "
-                                         "closed file"));
-                                invalidate_remote_inode(direntry->d_inode);
-                        }
-                }
-        }
-/*      mutex_unlock(&direntry->d_inode->i_mutex); */
+check_inval:
+        if (CIFS_I(inode)->invalid_mapping)
+                cifs_invalidate_mapping(inode);
 
         kfree(full_path);
         FreeXid(xid);
@@ -1527,7 +1512,7 @@ int cifs_revalidate(struct dentry *direntry)
 int cifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
         struct kstat *stat)
 {
-        int err = cifs_revalidate(dentry);
+        int err = cifs_revalidate_dentry(dentry);
         if (!err) {
                 generic_fillattr(dentry->d_inode, stat);
                 stat->blksize = CIFS_MAX_MSGSIZE;