]> git.proxmox.com Git - mirror_ubuntu-focal-kernel.git/blobdiff - fs/nfs/dir.c
NFS: Don't hash the negative dentry when optimising for an O_EXCL open
[mirror_ubuntu-focal-kernel.git] / fs / nfs / dir.c
index ea97408e423e916bf77ef5b303541a23551d2cb3..166a833be6611910d69ac5b4add99bb9f76a69fe 100644 (file)
@@ -200,9 +200,6 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page)
        desc->timestamp = timestamp;
        desc->timestamp_valid = 1;
        SetPageUptodate(page);
-       spin_lock(&inode->i_lock);
-       NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
-       spin_unlock(&inode->i_lock);
        /* Ensure consistent page alignment of the data.
         * Note: assumes we have exclusive access to this mapping either
         *       through inode->i_mutex or some other mechanism.
@@ -407,7 +404,7 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
        struct file     *file = desc->file;
        struct nfs_entry *entry = desc->entry;
        struct dentry   *dentry = NULL;
-       unsigned long   fileid;
+       u64             fileid;
        int             loop_count = 0,
                        res;
 
@@ -418,7 +415,7 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
                unsigned d_type = DT_UNKNOWN;
                /* Note: entry->prev_cookie contains the cookie for
                 *       retrieving the current dirent on the server */
-               fileid = nfs_fileid_to_ino_t(entry->ino);
+               fileid = entry->ino;
 
                /* Get a dentry if we have one */
                if (dentry != NULL)
@@ -428,7 +425,7 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
                /* Use readdirplus info */
                if (dentry != NULL && dentry->d_inode != NULL) {
                        d_type = dt_type(dentry->d_inode);
-                       fileid = dentry->d_inode->i_ino;
+                       fileid = NFS_FILEID(dentry->d_inode);
                }
 
                res = filldir(dirent, entry->name, entry->len, 
@@ -490,9 +487,6 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
                                                page,
                                                NFS_SERVER(inode)->dtsize,
                                                desc->plus);
-       spin_lock(&inode->i_lock);
-       NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
-       spin_unlock(&inode->i_lock);
        desc->page = page;
        desc->ptr = kmap(page);         /* matching kunmap in nfs_do_filldir */
        if (desc->error >= 0) {
@@ -558,7 +552,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
        memset(desc, 0, sizeof(*desc));
 
        desc->file = filp;
-       desc->dir_cookie = &((struct nfs_open_context *)filp->private_data)->dir_cookie;
+       desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie;
        desc->decode = NFS_PROTO(inode)->decode_dirent;
        desc->plus = NFS_USE_READDIRPLUS(inode);
 
@@ -623,7 +617,7 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
        }
        if (offset != filp->f_pos) {
                filp->f_pos = offset;
-               ((struct nfs_open_context *)filp->private_data)->dir_cookie = 0;
+               nfs_file_open_context(filp)->dir_cookie = 0;
        }
 out:
        mutex_unlock(&filp->f_path.dentry->d_inode->i_mutex);
@@ -650,15 +644,11 @@ static int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync)
  */
 static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
 {
-       unsigned long verf;
-
        if (IS_ROOT(dentry))
                return 1;
-       verf = dentry->d_time;
-       if (nfs_caches_unstable(dir)
-                       || verf != NFS_I(dir)->cache_change_attribute)
-               return 0;
-       return 1;
+       if (nfs_verify_change_attribute(dir, dentry->d_time))
+               return 1;
+       return 0;
 }
 
 static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
@@ -666,20 +656,6 @@ static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
        dentry->d_time = verf;
 }
 
-static void nfs_refresh_verifier(struct dentry * dentry, unsigned long verf)
-{
-       nfs_set_verifier(dentry, verf);
-}
-
-/*
- * Whenever an NFS operation succeeds, we know that the dentry
- * is valid, so we update the revalidation timestamp.
- */
-static inline void nfs_renew_times(struct dentry * dentry)
-{
-       dentry->d_time = jiffies;
-}
-
 /*
  * Return the intent data that applies to this particular path component
  *
@@ -803,8 +779,7 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
        if ((error = nfs_refresh_inode(inode, &fattr)) != 0)
                goto out_bad;
 
-       nfs_renew_times(dentry);
-       nfs_refresh_verifier(dentry, verifier);
+       nfs_set_verifier(dentry, verifier);
  out_valid:
        unlock_kernel();
        dput(parent);
@@ -872,8 +847,6 @@ static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
                nfs_complete_unlink(dentry, inode);
                unlock_kernel();
        }
-       /* When creating a negative dentry, we want to renew d_time */
-       nfs_renew_times(dentry);
        iput(inode);
 }
 
@@ -968,7 +941,6 @@ no_entry:
                dput(parent);
                dentry = res;
        }
-       nfs_renew_times(dentry);
        nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 out_unlock:
        unlock_kernel();
@@ -1020,9 +992,10 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
        }
        dentry->d_op = NFS_PROTO(dir)->dentry_ops;
 
-       /* Let vfs_create() deal with O_EXCL */
+       /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
+        * the dentry. */
        if (nd->intent.open.flags & O_EXCL) {
-               d_add(dentry, NULL);
+               d_instantiate(dentry, NULL);
                goto out;
        }
 
@@ -1063,7 +1036,6 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
                }
        } else if (res != NULL)
                dentry = res;
-       nfs_renew_times(dentry);
        nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 out:
        return res;
@@ -1107,7 +1079,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
        verifier = nfs_save_change_attribute(dir);
        ret = nfs4_open_revalidate(dir, dentry, openflags, nd);
        if (!ret)
-               nfs_refresh_verifier(dentry, verifier);
+               nfs_set_verifier(dentry, verifier);
        unlock_kernel();
 out:
        dput(parent);
@@ -1133,6 +1105,7 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
                .len = entry->len,
        };
        struct inode *inode;
+       unsigned long verf = nfs_save_change_attribute(dir);
 
        switch (name.len) {
                case 2:
@@ -1143,6 +1116,14 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
                        if (name.name[0] == '.')
                                return dget(parent);
        }
+
+       spin_lock(&dir->i_lock);
+       if (NFS_I(dir)->cache_validity & NFS_INO_INVALID_DATA) {
+               spin_unlock(&dir->i_lock);
+               return NULL;
+       }
+       spin_unlock(&dir->i_lock);
+
        name.hash = full_name_hash(name.name, name.len);
        dentry = d_lookup(parent, &name);
        if (dentry != NULL) {
@@ -1162,6 +1143,8 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
        }
        if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR))
                return NULL;
+       if (name.len > NFS_SERVER(dir)->namelen)
+               return NULL;
        /* Note: caller is already holding the dir->i_mutex! */
        dentry = d_alloc(parent, &name);
        if (dentry == NULL)
@@ -1181,12 +1164,8 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
                dentry = alias;
        }
 
-       nfs_renew_times(dentry);
-       nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
-       return dentry;
 out_renew:
-       nfs_renew_times(dentry);
-       nfs_refresh_verifier(dentry, nfs_save_change_attribute(dir));
+       nfs_set_verifier(dentry, verf);
        return dentry;
 }
 
@@ -1196,32 +1175,40 @@ out_renew:
 int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
                                struct nfs_fattr *fattr)
 {
+       struct dentry *parent = dget_parent(dentry);
+       struct inode *dir = parent->d_inode;
        struct inode *inode;
        int error = -EACCES;
 
+       d_drop(dentry);
+
        /* We may have been initialized further down */
        if (dentry->d_inode)
-               return 0;
+               goto out;
        if (fhandle->size == 0) {
-               struct inode *dir = dentry->d_parent->d_inode;
                error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
                if (error)
-                       return error;
+                       goto out_error;
        }
+       nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        if (!(fattr->valid & NFS_ATTR_FATTR)) {
                struct nfs_server *server = NFS_SB(dentry->d_sb);
                error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
                if (error < 0)
-                       return error;
+                       goto out_error;
        }
        inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
        error = PTR_ERR(inode);
        if (IS_ERR(inode))
-               return error;
-       d_instantiate(dentry, inode);
-       if (d_unhashed(dentry))
-               d_rehash(dentry);
+               goto out_error;
+       d_add(dentry, inode);
+out:
+       dput(parent);
        return 0;
+out_error:
+       nfs_mark_for_revalidate(dir);
+       dput(parent);
+       return error;
 }
 
 /*
@@ -1252,8 +1239,6 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
        nfs_end_data_update(dir);
        if (error != 0)
                goto out_err;
-       nfs_renew_times(dentry);
-       nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        unlock_kernel();
        return 0;
 out_err:
@@ -1286,8 +1271,6 @@ nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
        nfs_end_data_update(dir);
        if (status != 0)
                goto out_err;
-       nfs_renew_times(dentry);
-       nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        unlock_kernel();
        return 0;
 out_err:
@@ -1316,8 +1299,6 @@ static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
        nfs_end_data_update(dir);
        if (error != 0)
                goto out_err;
-       nfs_renew_times(dentry);
-       nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        unlock_kernel();
        return 0;
 out_err:
@@ -1348,9 +1329,9 @@ static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
 static int nfs_sillyrename(struct inode *dir, struct dentry *dentry)
 {
        static unsigned int sillycounter;
-       const int      i_inosize  = sizeof(dir->i_ino)*2;
+       const int      fileidsize  = sizeof(NFS_FILEID(dentry->d_inode))*2;
        const int      countersize = sizeof(sillycounter)*2;
-       const int      slen       = sizeof(".nfs") + i_inosize + countersize - 1;
+       const int      slen        = sizeof(".nfs")+fileidsize+countersize-1;
        char           silly[slen+1];
        struct qstr    qsilly;
        struct dentry *sdentry;
@@ -1368,8 +1349,9 @@ static int nfs_sillyrename(struct inode *dir, struct dentry *dentry)
        if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
                goto out;
 
-       sprintf(silly, ".nfs%*.*lx",
-               i_inosize, i_inosize, dentry->d_inode->i_ino);
+       sprintf(silly, ".nfs%*.*Lx",
+               fileidsize, fileidsize,
+               (unsigned long long)NFS_FILEID(dentry->d_inode));
 
        /* Return delegation in anticipation of the rename */
        nfs_inode_return_delegation(dentry->d_inode);
@@ -1408,7 +1390,6 @@ static int nfs_sillyrename(struct inode *dir, struct dentry *dentry)
                                dir, &qsilly);
        nfs_end_data_update(dir);
        if (!error) {
-               nfs_renew_times(dentry);
                nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
                d_move(dentry, sdentry);
                error = nfs_async_unlink(dir, dentry);
@@ -1491,7 +1472,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
        spin_unlock(&dcache_lock);
        error = nfs_safe_remove(dentry);
        if (!error) {
-               nfs_renew_times(dentry);
                nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        } else if (need_rehash)
                d_rehash(dentry);
@@ -1713,8 +1693,8 @@ out:
                d_rehash(rehash);
        if (!error) {
                d_move(old_dentry, new_dentry);
-               nfs_renew_times(new_dentry);
-               nfs_refresh_verifier(new_dentry, nfs_save_change_attribute(new_dir));
+               nfs_set_verifier(new_dentry,
+                                       nfs_save_change_attribute(new_dir));
        }
 
        /* new dentry created? */
@@ -1840,7 +1820,7 @@ static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, st
        return NULL;
 }
 
-int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
+static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
 {
        struct nfs_inode *nfsi = NFS_I(inode);
        struct nfs_access_entry *cache;
@@ -1852,7 +1832,7 @@ int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs
        cache = nfs_access_search_rbtree(inode, cred);
        if (cache == NULL)
                goto out;
-       if (time_after(jiffies, cache->jiffies + NFS_ATTRTIMEO(inode)))
+       if (!time_in_range(jiffies, cache->jiffies, cache->jiffies + NFS_ATTRTIMEO(inode)))
                goto out_stale;
        res->jiffies = cache->jiffies;
        res->cred = cache->cred;
@@ -1907,7 +1887,7 @@ found:
        nfs_access_free_entry(entry);
 }
 
-void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
+static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
 {
        struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
        if (cache == NULL)
@@ -1955,6 +1935,24 @@ out:
        return -EACCES;
 }
 
+static int nfs_open_permission_mask(int openflags)
+{
+       int mask = 0;
+
+       if (openflags & FMODE_READ)
+               mask |= MAY_READ;
+       if (openflags & FMODE_WRITE)
+               mask |= MAY_WRITE;
+       if (openflags & FMODE_EXEC)
+               mask |= MAY_EXEC;
+       return mask;
+}
+
+int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
+{
+       return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
+}
+
 int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
 {
        struct rpc_cred *cred;