1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * Copyright (C) 2002 Cluster File Systems, Inc.
8 * This code is issued under the GNU General Public License.
9 * See the file COPYING in this distribution
11 * by Peter Braam <braam@clusterfs.com>
12 * and Andreas Dilger <adilger@clusterfs.com>
17 #include <linux/version.h>
19 #include <asm/unistd.h>
21 #define DEBUG_SUBSYSTEM S_FILTER
23 #include <linux/obd_support.h>
24 #include <linux/obd.h>
25 #include <linux/lustre_mds.h>
26 #include <linux/lustre_lib.h>
27 #include <linux/lustre_net.h>
30 /* Debugging check only needed during development */
31 #define ASSERT_CTXT_MAGIC(magic) do { if ((magic) != OBD_RUN_CTXT_MAGIC) { \
32 CERROR("bad ctxt magic\n"); LBUG(); } } while(0)
33 #define ASSERT_NOT_KERNEL_CTXT(msg) do { if (segment_eq(get_fs(), get_ds())) { \
34 CERROR(msg); LBUG(); } } while(0)
35 #define ASSERT_KERNEL_CTXT(msg) do { if (!segment_eq(get_fs(), get_ds())) { \
36 CERROR(msg); LBUG(); } } while(0)
38 #define ASSERT_CTXT_MAGIC(magic) do {} while(0)
39 #define ASSERT_NOT_KERNEL_CTXT(msg) do {} while(0)
40 #define ASSERT_KERNEL_CTXT(msg) do {} while(0)
43 /* push / pop to root of obd store */
44 void push_ctxt(struct obd_run_ctxt *save, struct obd_run_ctxt *new,
47 //ASSERT_NOT_KERNEL_CTXT("already in kernel context!\n");
48 ASSERT_CTXT_MAGIC(new->magic);
49 OBD_SET_CTXT_MAGIC(save);
51 save->pwd = dget(current->fs->pwd);
52 save->pwdmnt = mntget(current->fs->pwdmnt);
55 LASSERT(save->pwdmnt);
59 save->fsuid = current->fsuid;
60 save->fsgid = current->fsgid;
62 current->fsuid = uc->ouc_fsuid;
63 current->fsgid = uc->ouc_fsgid;
66 set_fs_pwd(current->fs, new->pwdmnt, new->pwd);
69 void pop_ctxt(struct obd_run_ctxt *saved)
72 ASSERT_CTXT_MAGIC(saved->magic);
74 ASSERT_KERNEL_CTXT("popping non-kernel context!\n");
78 set_fs_pwd(current->fs, saved->pwdmnt, saved->pwd);
83 mntput(saved->pwdmnt);
85 current->fsuid = saved->fsuid;
86 current->fsgid = saved->fsgid;
89 /* utility to make a file */
90 struct dentry *simple_mknod(struct dentry *dir, char *name, int mode)
92 struct dentry *dchild;
96 ASSERT_KERNEL_CTXT("kernel doing mknod outside kernel context\n");
97 CDEBUG(D_INODE, "creating file %*s\n", (int)strlen(name), name);
98 down(&dir->d_inode->i_sem);
99 dchild = lookup_one_len(name, dir, strlen(name));
101 GOTO(out, PTR_ERR(dchild));
103 if (dchild->d_inode) {
104 if (((dchild->d_inode->i_mode ^ mode) & S_IFMT) != 0)
105 GOTO(out, err = -EEXIST);
110 err = vfs_create(dir->d_inode, dchild, (mode & S_IFMT) | S_IFREG);
113 up(&dir->d_inode->i_sem);
116 RETURN(ERR_PTR(err));
122 /* utility to make a directory */
123 struct dentry *simple_mkdir(struct dentry *dir, char *name, int mode)
125 struct dentry *dchild;
129 ASSERT_KERNEL_CTXT("kernel doing mkdir outside kernel context\n");
130 CDEBUG(D_INODE, "creating directory %*s\n", (int)strlen(name), name);
131 down(&dir->d_inode->i_sem);
132 dchild = lookup_one_len(name, dir, strlen(name));
134 GOTO(out, PTR_ERR(dchild));
136 if (dchild->d_inode) {
137 if (!S_ISDIR(dchild->d_inode->i_mode))
138 GOTO(out, err = -ENOTDIR);
143 err = vfs_mkdir(dir->d_inode, dchild, mode);
146 up(&dir->d_inode->i_sem);
149 RETURN(ERR_PTR(err));
156 * Read a file from within kernel context. Prior to calling this
157 * function we should already have done a push_ctxt().
159 int lustre_fread(struct file *file, char *str, int len, loff_t *off)
161 ASSERT_KERNEL_CTXT("kernel doing read outside kernel context\n");
162 if (!file || !file->f_op || !file->f_op->read || !off)
165 return file->f_op->read(file, str, len, off);
169 * Write a file from within kernel context. Prior to calling this
170 * function we should already have done a push_ctxt().
172 int lustre_fwrite(struct file *file, const char *str, int len, loff_t *off)
174 ASSERT_KERNEL_CTXT("kernel doing write outside kernel context\n");
175 if (!file || !file->f_op || !off)
178 if (!file->f_op->write)
181 return file->f_op->write(file, str, len, off);
185 * Sync a file from within kernel context. Prior to calling this
186 * function we should already have done a push_ctxt().
188 int lustre_fsync(struct file *file)
190 ASSERT_KERNEL_CTXT("kernel doing sync outside kernel context\n");
191 if (!file || !file->f_op || !file->f_op->fsync)
194 return file->f_op->fsync(file, file->f_dentry, 0);