-/*
+/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
+ * vim:expandtab:shiftwidth=8:tabstop=8:
+ *
* lib/simple.c
*
* Copyright (C) 2002 Cluster File Systems, Inc.
#define DEBUG_SUBSYSTEM S_FILTER
+#include <linux/obd_support.h>
+#include <linux/obd.h>
#include <linux/lustre_mds.h>
#include <linux/lustre_lib.h>
#include <linux/lustre_net.h>
+#ifdef OBD_CTXT_DEBUG
+/* Debugging check only needed during development */
+#define ASSERT_CTXT_MAGIC(magic) do { if ((magic) != OBD_RUN_CTXT_MAGIC) { \
+ CERROR("bad ctxt magic\n"); LBUG(); } } while(0)
+#define ASSERT_NOT_KERNEL_CTXT(msg) do { if (segment_eq(get_fs(), get_ds())) { \
+ CERROR(msg); LBUG(); } } while(0)
+#define ASSERT_KERNEL_CTXT(msg) do { if (!segment_eq(get_fs(), get_ds())) { \
+ CERROR(msg); LBUG(); } } while(0)
+#else
+#define ASSERT_CTXT_MAGIC(magic) do {} while(0)
+#define ASSERT_NOT_KERNEL_CTXT(msg) do {} while(0)
+#define ASSERT_KERNEL_CTXT(msg) do {} while(0)
+#endif
+
+/* push / pop to root of obd store */
+void push_ctxt(struct obd_run_ctxt *save, struct obd_run_ctxt *new,
+ struct obd_ucred *uc)
+{
+ //ASSERT_NOT_KERNEL_CTXT("already in kernel context!\n");
+ ASSERT_CTXT_MAGIC(new->magic);
+ OBD_SET_CTXT_MAGIC(save);
+ save->fs = get_fs();
+ save->pwd = dget(current->fs->pwd);
+ save->pwdmnt = mntget(current->fs->pwdmnt);
+
+ LASSERT(save->pwd);
+ LASSERT(save->pwdmnt);
+ LASSERT(new->pwd);
+ LASSERT(new->pwdmnt);
+
+ save->fsuid = current->fsuid;
+ save->fsgid = current->fsgid;
+ save->cap = current->cap_effective;
+ if (uc) {
+ current->fsuid = uc->ouc_fsuid;
+ current->fsgid = uc->ouc_fsgid;
+ current->cap_effective = uc->ouc_cap;
+ }
+ set_fs(new->fs);
+ set_fs_pwd(current->fs, new->pwdmnt, new->pwd);
+ //if (save->override)
+ // cap_lower(current->cap_effective, CAP_DAC_OVERRIDE);
+}
+
+void pop_ctxt(struct obd_run_ctxt *saved)
+{
+ //printk("pc0");
+ ASSERT_CTXT_MAGIC(saved->magic);
+ //printk("pc1");
+ ASSERT_KERNEL_CTXT("popping non-kernel context!\n");
+ //printk("pc2");
+ set_fs(saved->fs);
+ //printk("pc3\n");
+ set_fs_pwd(current->fs, saved->pwdmnt, saved->pwd);
+ //printk("pc4");
+
+ dput(saved->pwd);
+ //printk("pc5");
+ mntput(saved->pwdmnt);
+ //printk("pc6\n");
+ current->fsuid = saved->fsuid;
+ current->fsgid = saved->fsgid;
+ current->cap_effective = saved->cap;
+
+ // if (saved->override)
+ // cap_raise(current->cap_effective, CAP_DAC_OVERRIDE);
+}
+
+/* utility to make a file */
+struct dentry *simple_mknod(struct dentry *dir, char *name, int mode)
+{
+ struct dentry *dchild;
+ int err = 0;
+ ENTRY;
+
+ ASSERT_KERNEL_CTXT("kernel doing mknod outside kernel context\n");
+ CDEBUG(D_INODE, "creating file %*s\n", (int)strlen(name), name);
+
+ down(&dir->d_inode->i_sem);
+ dchild = lookup_one_len(name, dir, strlen(name));
+ if (IS_ERR(dchild))
+ GOTO(out, PTR_ERR(dchild));
+
+ if (dchild->d_inode) {
+ if ((dchild->d_inode->i_mode & S_IFMT) != S_IFREG)
+ GOTO(out, err = -EEXIST);
+
+ GOTO(out, dchild);
+ }
+
+ err = vfs_create(dir->d_inode, dchild, (mode & ~S_IFMT) | S_IFREG);
+ EXIT;
+out:
+ up(&dir->d_inode->i_sem);
+ if (err) {
+ dput(dchild);
+ RETURN(ERR_PTR(err));
+ }
+
+ RETURN(dchild);
+}
+
/* utility to make a directory */
-int simple_mkdir(struct dentry *dir, char *name, int mode)
+struct dentry *simple_mkdir(struct dentry *dir, char *name, int mode)
{
struct dentry *dchild;
- int err;
+ int err = 0;
ENTRY;
+ ASSERT_KERNEL_CTXT("kernel doing mkdir outside kernel context\n");
+ CDEBUG(D_INODE, "creating directory %*s\n", (int)strlen(name), name);
+ down(&dir->d_inode->i_sem);
dchild = lookup_one_len(name, dir, strlen(name));
if (IS_ERR(dchild))
- RETURN(PTR_ERR(dchild));
+ GOTO(out, PTR_ERR(dchild));
- if (dchild->d_inode)
- GOTO(out, err = -EEXIST);
+ if (dchild->d_inode) {
+ if (!S_ISDIR(dchild->d_inode->i_mode))
+ GOTO(out, err = -ENOTDIR);
+
+ GOTO(out, dchild);
+ }
err = vfs_mkdir(dir->d_inode, dchild, mode);
+ EXIT;
out:
- l_dput(dchild);
+ up(&dir->d_inode->i_sem);
+ if (err) {
+ dput(dchild);
+ RETURN(ERR_PTR(err));
+ }
+
+ RETURN(dchild);
+}
+
+/*
+ * Read a file from within kernel context. Prior to calling this
+ * function we should already have done a push_ctxt().
+ */
+int lustre_fread(struct file *file, char *str, int len, loff_t *off)
+{
+ ASSERT_KERNEL_CTXT("kernel doing read outside kernel context\n");
+ if (!file || !file->f_op || !file->f_op->read || !off)
+ RETURN(-ENOSYS);
+
+ return file->f_op->read(file, str, len, off);
+}
+
+/*
+ * Write a file from within kernel context. Prior to calling this
+ * function we should already have done a push_ctxt().
+ */
+int lustre_fwrite(struct file *file, const char *str, int len, loff_t *off)
+{
+ ASSERT_KERNEL_CTXT("kernel doing write outside kernel context\n");
+ if (!file || !file->f_op || !off)
+ RETURN(-ENOSYS);
+
+ if (!file->f_op->write)
+ RETURN(-EROFS);
+
+ return file->f_op->write(file, str, len, off);
+}
+
+/*
+ * Sync a file from within kernel context. Prior to calling this
+ * function we should already have done a push_ctxt().
+ */
+int lustre_fsync(struct file *file)
+{
+ ASSERT_KERNEL_CTXT("kernel doing sync outside kernel context\n");
+ if (!file || !file->f_op || !file->f_op->fsync)
+ RETURN(-ENOSYS);
- RETURN(err);
+ return file->f_op->fsync(file, file->f_dentry, 0);
}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff