Delay before destroying loopback devices

[zfs.git] / module / zfs / zpl_file.c

diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c
index 585f971..de66ff4 100644 (file)
--- a/module/zfs/zpl_file.c
+++ b/module/zfs/zpl_file.c
@@ -30,30 +30,79 @@
 
 
 static int
+zpl_open(struct inode *ip, struct file *filp)
+{
+       cred_t *cr = CRED();
+       int error;
+
+       crhold(cr);
+       error = -zfs_open(ip, filp->f_mode, filp->f_flags, cr);
+       crfree(cr);
+       ASSERT3S(error, <=, 0);
+
+       if (error)
+               return (error);
+
+       return generic_file_open(ip, filp);
+}
+
+static int
+zpl_release(struct inode *ip, struct file *filp)
+{
+       cred_t *cr = CRED();
+       int error;
+
+       crhold(cr);
+       error = -zfs_close(ip, filp->f_flags, cr);
+       crfree(cr);
+       ASSERT3S(error, <=, 0);
+
+       return (error);
+}
+
+static int
 zpl_readdir(struct file *filp, void *dirent, filldir_t filldir)
 {
        struct dentry *dentry = filp->f_path.dentry;
-       cred_t *cr;
+       cred_t *cr = CRED();
        int error;
 
-       cr = (cred_t *)get_current_cred();
+       crhold(cr);
        error = -zfs_readdir(dentry->d_inode, dirent, filldir,
            &filp->f_pos, cr);
-       put_cred(cr);
+       crfree(cr);
        ASSERT3S(error, <=, 0);
 
        return (error);
 }
 
+/*
+ * 2.6.35 API change,
+ * As of 2.6.35 the dentry argument to the .fsync() vfs hook was deemed
+ * redundant.  The dentry is still accessible via filp->f_path.dentry,
+ * and we are guaranteed that filp will never be NULL.
+ *
+ * 2.6.34 API change,
+ * Prior to 2.6.34 the nfsd kernel server would pass a NULL file struct *
+ * to the .fsync() hook.  For this reason, we must be careful not to use
+ * filp unconditionally in the 3 argument case.
+ */
+#ifdef HAVE_2ARGS_FSYNC
+static int
+zpl_fsync(struct file *filp, int datasync)
+{
+       struct dentry *dentry = filp->f_path.dentry;
+#else
 static int
 zpl_fsync(struct file *filp, struct dentry *dentry, int datasync)
 {
-       cred_t *cr;
+#endif /* HAVE_2ARGS_FSYNC */
+       cred_t *cr = CRED();
        int error;
 
-       cr = (cred_t *)get_current_cred();
-       error = -zfs_fsync(filp->f_path.dentry->d_inode, datasync, cr);
-       put_cred(cr);
+       crhold(cr);
+       error = -zfs_fsync(dentry->d_inode, datasync, cr);
+       crfree(cr);
        ASSERT3S(error, <=, 0);
 
        return (error);
@@ -87,13 +136,13 @@ zpl_read_common(struct inode *ip, const char *buf, size_t len, loff_t pos,
 static ssize_t
 zpl_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
 {
-       cred_t *cr;
+       cred_t *cr = CRED();
        ssize_t read;
 
-       cr = (cred_t *)get_current_cred();
+       crhold(cr);
        read = zpl_read_common(filp->f_mapping->host, buf, len, *ppos,
            UIO_USERSPACE, filp->f_flags, cr);
-       put_cred(cr);
+       crfree(cr);
 
        if (read < 0)
                return (read);
@@ -130,13 +179,13 @@ zpl_write_common(struct inode *ip, const char *buf, size_t len, loff_t pos,
 static ssize_t
 zpl_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
 {
-       cred_t *cr;
+       cred_t *cr = CRED();
        ssize_t wrote;
 
-       cr = (cred_t *)get_current_cred();
+       crhold(cr);
        wrote = zpl_write_common(filp->f_mapping->host, buf, len, *ppos,
            UIO_USERSPACE, filp->f_flags, cr);
-       put_cred(cr);
+       crfree(cr);
 
        if (wrote < 0)
                return (wrote);
@@ -220,7 +269,7 @@ zpl_readpage(struct file *filp, struct page *pp)
        struct inode *ip;
        loff_t off, i_size;
        size_t len, wrote;
-       cred_t *cr;
+       cred_t *cr = CRED();
        void *pb;
        int error = 0;
 
@@ -230,7 +279,7 @@ zpl_readpage(struct file *filp, struct page *pp)
        i_size = i_size_read(ip);
        ASSERT3S(off, <, i_size);
 
-       cr = (cred_t *)get_current_cred();
+       crhold(cr);
        len = MIN(PAGE_CACHE_SIZE, i_size - off);
 
        pb = kmap(pp);
@@ -244,7 +293,7 @@ zpl_readpage(struct file *filp, struct page *pp)
                memset(pb + len, 0, PAGE_CACHE_SIZE - len);
 
        kunmap(pp);
-       put_cred(cr);
+       crfree(cr);
 
        if (error) {
                SetPageError(pp);
@@ -276,7 +325,7 @@ zpl_writepage(struct page *pp, struct writeback_control *wbc)
        struct inode *ip;
        loff_t off, i_size;
        size_t len, read;
-       cred_t *cr;
+       cred_t *cr = CRED();
        void *pb;
        int error = 0;
 
@@ -285,7 +334,7 @@ zpl_writepage(struct page *pp, struct writeback_control *wbc)
        off = page_offset(pp);
        i_size = i_size_read(ip);
 
-       cr = (cred_t *)get_current_cred();
+       crhold(cr);
        len = MIN(PAGE_CACHE_SIZE, i_size - off);
 
        pb = kmap(pp);
@@ -296,7 +345,7 @@ zpl_writepage(struct page *pp, struct writeback_control *wbc)
                error = -EIO;
 
        kunmap(pp);
-       put_cred(cr);
+       crfree(cr);
 
        if (error) {
                SetPageError(pp);
@@ -317,7 +366,8 @@ const struct address_space_operations zpl_address_space_operations = {
 };
 
 const struct file_operations zpl_file_operations = {
-       .open           = generic_file_open,
+       .open           = zpl_open,
+       .release        = zpl_release,
        .llseek         = generic_file_llseek,
        .read           = zpl_read,
        .write          = zpl_write,