--- /dev/null
+/*
+ * Copyright (c) 2003-2007 Erez Zadok
+ * Copyright (c) 2005-2007 Josef 'Jeff' Sipek
+ * Copyright (c) 2003-2007 Stony Brook University
+ * Copyright (c) 2003-2007 The Research Foundation of SUNY
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "union.h"
+
+/*
+ * Helper debugging functions for maintainers (and for users to report back
+ * useful information back to maintainers)
+ */
+
+/* it's always useful to know what part of the code called us */
+#define PRINT_CALLER \
+do { \
+ if (!printed_caller) { \
+ printk("PC:%s:%s:%d\n",fname,fxn,line); \
+ printed_caller = 1; \
+ } \
+ } while (0)
+
+/*
+ * __unionfs_check_{inode,dentry,file} perform exhaustive sanity checking on
+ * the fan-out of various Unionfs objects. We check that no lower objects
+ * exist outside the start/end branch range; that all objects within are
+ * non-NULL (with some allowed exceptions); that for every lower file
+ * there's a lower dentry+inode; that the start/end ranges match for all
+ * corresponding lower objects; that open files/symlinks have only one lower
+ * objects, but directories can have several; and more.
+ */
+void __unionfs_check_inode(const struct inode *inode,
+ const char *fname, const char *fxn, int line)
+{
+ int bindex;
+ int istart, iend;
+ struct inode *lower_inode;
+ struct super_block *sb;
+ int printed_caller = 0;
+
+ printk("_PCi(%ld:%o):%p:%s:%s:%d\n",
+ inode->i_ino,inode->i_mode,inode,fname,fxn,line);
+ /* for inodes now */
+ BUG_ON(!inode);
+ sb = inode->i_sb;
+ istart = ibstart(inode);
+ iend = ibend(inode);
+ if (istart > iend) {
+ PRINT_CALLER;
+ printk(" Ci0: inode=%p istart/end=%d:%d\n",
+ inode, istart, iend);
+ }
+ if ((istart == -1 && iend != -1) ||
+ (istart != -1 && iend == -1)) {
+ PRINT_CALLER;
+ printk(" Ci1: inode=%p istart/end=%d:%d\n",
+ inode, istart, iend);
+ }
+ if (!S_ISDIR(inode->i_mode)) {
+ if (iend != istart) {
+ PRINT_CALLER;
+ printk(" Ci2: inode=%p istart=%d iend=%d\n",
+ inode, istart, iend);
+ }
+ }
+
+ for (bindex = sbstart(sb); bindex < sbmax(sb); bindex++) {
+ if (!UNIONFS_I(inode)) {
+ PRINT_CALLER;
+ printk(" Ci3: no inode_info %p\n", inode);
+ return;
+ }
+ if (!UNIONFS_I(inode)->lower_inodes) {
+ PRINT_CALLER;
+ printk(" Ci4: no lower_inodes %p\n", inode);
+ return;
+ }
+ lower_inode = unionfs_lower_inode_idx(inode, bindex);
+ if (lower_inode) {
+ if (bindex < istart || bindex > iend) {
+ PRINT_CALLER;
+ printk(" Ci5: inode/linode=%p:%p bindex=%d istart/end=%d:%d\n",
+ inode, lower_inode, bindex, istart, iend);
+ }
+ } else { /* lower_inode == NULL */
+ if (bindex >= istart && bindex <= iend) {
+ /*
+ * directories can have NULL lower inodes in b/t start/end, but
+ * NOT if at the start/end range.
+ */
+ if (!(S_ISDIR(inode->i_mode) && bindex > istart && bindex < iend)) {
+ PRINT_CALLER;
+ printk(" Ci6: inode/linode=%p:%p bindex=%d istart/end=%d:%d\n",
+ inode, lower_inode, bindex, istart, iend);
+ }
+ }
+ }
+ }
+}
+
+void __unionfs_check_dentry(const struct dentry *dentry,
+ const char *fname, const char *fxn, int line)
+{
+ int bindex;
+ int dstart, dend, istart, iend;
+ struct dentry *lower_dentry;
+ struct inode *inode, *lower_inode;
+ struct super_block *sb;
+ struct vfsmount *lower_mnt;
+ int printed_caller = 0;
+
+ printk("_PCd(%s):%p:%p:%s:%s:%d\n",dentry->d_name.name,dentry,dentry->d_inode,
+ fname,fxn,line);
+ BUG_ON(!dentry);
+ sb = dentry->d_sb;
+ inode = dentry->d_inode;
+ dstart = dbstart(dentry);
+ dend = dbend(dentry);
+ BUG_ON(dstart > dend);
+
+ if ((dstart == -1 && dend != -1) ||
+ (dstart != -1 && dend == -1)) {
+ PRINT_CALLER;
+ printk(" CD0: dentry=%p dstart/end=%d:%d\n",
+ dentry, dstart, dend);
+ }
+ /*
+ * check for NULL dentries inside the start/end range, or
+ * non-NULL dentries outside the start/end range.
+ */
+ for (bindex = sbstart(sb); bindex < sbmax(sb); bindex++) {
+ lower_dentry = unionfs_lower_dentry_idx(dentry, bindex);
+ if (lower_dentry) {
+ if (bindex < dstart || bindex > dend) {
+ PRINT_CALLER;
+ printk(" CD1: dentry/lower=%p:%p(%p) bindex=%d dstart/end=%d:%d\n",
+ dentry, lower_dentry,
+ (lower_dentry ? lower_dentry->d_inode : (void *) 0xffffffff),
+ bindex, dstart, dend);
+ }
+ } else { /* lower_dentry == NULL */
+ if (bindex >= dstart && bindex <= dend) {
+ /*
+ * Directories can have NULL lower inodes in b/t start/end, but NOT
+ * if at the start/end range. Ignore this rule, however, if this is
+ * a NULL dentry.
+ */
+ if (inode && !(inode && S_ISDIR(inode->i_mode) &&
+ bindex > dstart && bindex < dend)) {
+ PRINT_CALLER;
+ printk(" CD2: dentry/lower=%p:%p(%p) bindex=%d dstart/end=%d:%d\n",
+ dentry, lower_dentry,
+ (lower_dentry ? lower_dentry->d_inode : (void *) 0xffffffff),
+ bindex, dstart, dend);
+ }
+ }
+ }
+ }
+
+ /* check for vfsmounts same as for dentries */
+ for (bindex = sbstart(sb); bindex < sbmax(sb); bindex++) {
+ lower_mnt = unionfs_lower_mnt_idx(dentry, bindex);
+ if (lower_mnt) {
+ if (bindex < dstart || bindex > dend) {
+ PRINT_CALLER;
+ printk(" CM0: dentry/lmnt=%p:%p bindex=%d dstart/end=%d:%d\n",
+ dentry, lower_mnt, bindex, dstart, dend);
+ }
+ } else { /* lower_mnt == NULL */
+ if (bindex >= dstart && bindex <= dend) {
+ /*
+ * Directories can have NULL lower inodes in b/t start/end, but NOT
+ * if at the start/end range. Ignore this rule, however, if this is
+ * a NULL dentry.
+ */
+ if (inode && !(inode && S_ISDIR(inode->i_mode) &&
+ bindex > dstart && bindex < dend)) {
+ PRINT_CALLER;
+ printk(" CM1: dentry/lmnt=%p:%p bindex=%d dstart/end=%d:%d\n",
+ dentry, lower_mnt, bindex, dstart, dend);
+ }
+ }
+ }
+ }
+
+ /* for inodes now */
+ if (!inode)
+ return;
+ istart = ibstart(inode);
+ iend = ibend(inode);
+ BUG_ON(istart > iend);
+ if ((istart == -1 && iend != -1) ||
+ (istart != -1 && iend == -1)) {
+ PRINT_CALLER;
+ printk(" CI0: dentry/inode=%p:%p istart/end=%d:%d\n",
+ dentry, inode, istart, iend);
+ }
+ if (istart != dstart) {
+ PRINT_CALLER;
+ printk(" CI1: dentry/inode=%p:%p istart=%d dstart=%d\n",
+ dentry, inode, istart, dstart);
+ }
+ if (iend != dend) {
+ PRINT_CALLER;
+ printk(" CI2: dentry/inode=%p:%p iend=%d dend=%d\n",
+ dentry, inode, iend, dend);
+ }
+
+ if (!S_ISDIR(inode->i_mode)) {
+ if (dend != dstart) {
+ PRINT_CALLER;
+ printk(" CI3: dentry/inode=%p:%p dstart=%d dend=%d\n",
+ dentry, inode, dstart, dend);
+ }
+ if (iend != istart) {
+ PRINT_CALLER;
+ printk(" CI4: dentry/inode=%p:%p istart=%d iend=%d\n",
+ dentry, inode, istart, iend);
+ }
+ }
+
+ for (bindex = sbstart(sb); bindex < sbmax(sb); bindex++) {
+ lower_inode = unionfs_lower_inode_idx(inode, bindex);
+ if (lower_inode) {
+ if (bindex < istart || bindex > iend) {
+ PRINT_CALLER;
+ printk(" CI5: dentry/linode=%p:%p bindex=%d istart/end=%d:%d\n",
+ dentry, lower_inode, bindex, istart, iend);
+ }
+ } else { /* lower_inode == NULL */
+ if (bindex >= istart && bindex <= iend) {
+ /*
+ * directories can have NULL lower inodes in b/t start/end, but
+ * NOT if at the start/end range.
+ */
+ if (!(S_ISDIR(inode->i_mode) && bindex > istart && bindex < iend)) {
+ PRINT_CALLER;
+ printk(" CI6: dentry/linode=%p:%p bindex=%d istart/end=%d:%d\n",
+ dentry, lower_inode, bindex, istart, iend);
+ }
+ }
+ }
+ }
+
+ /*
+ * If it's a directory, then intermediate objects b/t start/end can be NULL.
+ * But, check that all three are NULL: lower dentry, mnt, and inode.
+ */
+ if (S_ISDIR(inode->i_mode))
+ for (bindex = dstart+1; bindex < dend-1; bindex++) {
+ lower_inode = unionfs_lower_inode_idx(inode, bindex);
+ lower_dentry = unionfs_lower_dentry_idx(dentry, bindex);
+ lower_mnt = unionfs_lower_mnt_idx(dentry, bindex);
+ if (!((lower_inode && lower_dentry && lower_mnt) ||
+ (!lower_inode && !lower_dentry && !lower_mnt)))
+ printk(" Cx: lmnt/ldentry/linode=%p:%p:%p bindex=%d dstart/end=%d:%d\n",
+ lower_mnt, lower_dentry, lower_inode, bindex, dstart, dend);
+ }
+}
+
+void __unionfs_check_file(const struct file *file,
+ const char *fname, const char *fxn, int line)
+{
+ int bindex;
+ int dstart, dend, fstart, fend;
+ struct dentry *dentry;
+ struct file *lower_file;
+ struct inode *inode;
+ struct super_block *sb;
+ int printed_caller = 0;
+
+ printk("_PCf(%s):%p:%s:%s:%d\n",file->f_dentry->d_name.name,file,fname,fxn,line);
+ BUG_ON(!file);
+ dentry = file->f_dentry;
+ sb = dentry->d_sb;
+ dstart = dbstart(dentry);
+ dend = dbend(dentry);
+ BUG_ON(dstart > dend);
+ fstart = fbstart(file);
+ fend = fbend(file);
+ BUG_ON(fstart > fend);
+
+ if ((fstart == -1 && fend != -1) ||
+ (fstart != -1 && fend == -1)) {
+ PRINT_CALLER;
+ printk(" CF0: file/dentry=%p:%p fstart/end=%d:%d\n",
+ file, dentry, fstart, fend);
+ }
+ if (fstart != dstart) {
+ PRINT_CALLER;
+ printk(" CF1: file/dentry=%p:%p fstart=%d dstart=%d\n",
+ file, dentry, fstart, dstart);
+ }
+ if (fend != dend) {
+ PRINT_CALLER;
+ printk(" CF2: file/dentry=%p:%p fend=%d dend=%d\n",
+ file, dentry, fend, dend);
+ }
+ inode = dentry->d_inode;
+ if (!S_ISDIR(inode->i_mode)) {
+ if (fend != fstart) {
+ PRINT_CALLER;
+ printk(" CF3: file/inode=%p:%p fstart=%d fend=%d\n",
+ file, inode, fstart, fend);
+ }
+ if (dend != dstart) {
+ PRINT_CALLER;
+ printk(" CF4: file/dentry=%p:%p dstart=%d dend=%d\n",
+ file, dentry, dstart, dend);
+ }
+ }
+
+ /*
+ * check for NULL dentries inside the start/end range, or
+ * non-NULL dentries outside the start/end range.
+ */
+ for (bindex = sbstart(sb); bindex < sbmax(sb); bindex++) {
+ lower_file = unionfs_lower_file_idx(file, bindex);
+ if (lower_file) {
+ if (bindex < fstart || bindex > fend) {
+ PRINT_CALLER;
+ printk(" CF5: file/lower=%p:%p bindex=%d fstart/end=%d:%d\n",
+ file, lower_file, bindex, fstart, fend);
+ }
+ } else { /* lower_file == NULL */
+ if (bindex >= fstart && bindex <= fend) {
+ /*
+ * directories can have NULL lower inodes in b/t start/end, but
+ * NOT if at the start/end range.
+ */
+ if (!(S_ISDIR(inode->i_mode) && bindex > fstart && bindex < fend)) {
+ PRINT_CALLER;
+ printk(" CF6: file/lower=%p:%p bindex=%d fstart/end=%d:%d\n",
+ file, lower_file, bindex, fstart, fend);
+ }
+ }
+ }
+ }
+
+ __unionfs_check_dentry(dentry,fname,fxn,line);
+}
+
+/* useful to track vfsmount leaks that could cause EBUSY on unmount */
+void __show_branch_counts(const struct super_block *sb,
+ const char *file, const char *fxn, int line)
+{
+ int i;
+ struct vfsmount *mnt;
+
+ printk("BC:");
+ for (i=0; i<4; i++) {
+ mnt = UNIONFS_D(sb->s_root)->lower_paths[i].mnt;
+ printk("%d:", (mnt ? atomic_read(&mnt->mnt_count) : -99));
+ }
+ printk("%s:%s:%d\n",file,fxn,line);
+}
if (!dentry) {
if (bindex < 0)
return NULL;
- BUG_ON(bindex < 0);
+ if (!dentry && bindex >= 0) {
+#ifdef UNIONFS_DEBUG
+ printk(KERN_DEBUG
+ "unionfs_mntget: dentry=%p bindex=%d\n",
+ dentry, bindex);
+#endif /* UNIONFS_DEBUG */
+ return NULL;
+ }
}
mnt = unionfs_lower_mnt_idx(dentry, bindex);
if (!mnt) {
if (bindex < 0)
return NULL;
- BUG_ON(mnt && bindex < 0);
+ if (!mnt && bindex >= 0) {
+#ifdef UNIONFS_DEBUG
+ printk(KERN_DEBUG
+ "unionfs_mntget: mnt=%p bindex=%d\n",
+ mnt, bindex);
+#endif /* UNIONFS_DEBUG */
+ return NULL;
+ }
}
mnt = mntget(mnt);
return mnt;
if (!dentry) {
if (bindex < 0)
return;
- BUG_ON(!dentry && bindex >= 0);
+ if (!dentry && bindex >= 0) {
+#ifdef UNIONFS_DEBUG
+ printk(KERN_DEBUG
+ "unionfs_mntput: dentry=%p bindex=%d\n",
+ dentry, bindex);
+#endif /* UNIONFS_DEBUG */
+ return;
+ }
}
mnt = unionfs_lower_mnt_idx(dentry, bindex);
if (!mnt) {
if (bindex < 0)
return;
- BUG_ON(!mnt && bindex >= 0);
+ if (!mnt && bindex >= 0) {
+#ifdef UNIONFS_DEBUG
+ printk(KERN_DEBUG
+ "unionfs_mntput: mnt=%p bindex=%d\n",
+ mnt, bindex);
+#endif /* UNIONFS_DEBUG */
+ return;
+ }
}
mntput(mnt);
}
+
+#ifdef UNIONFS_DEBUG
+
+/* useful for tracking code reachability */
+#define UDBG printk("DBG:%s:%s:%d\n",__FILE__,__FUNCTION__,__LINE__)
+
+#define unionfs_check_inode(i) __unionfs_check_inode((i),__FILE__,__FUNCTION__,__LINE__)
+#define unionfs_check_dentry(d) __unionfs_check_dentry((d),__FILE__,__FUNCTION__,__LINE__)
+#define unionfs_check_file(f) __unionfs_check_file((f),__FILE__,__FUNCTION__,__LINE__)
+#define show_branch_counts(sb) __show_branch_counts((sb),__FILE__,__FUNCTION__,__LINE__)
+extern void __unionfs_check_inode(const struct inode *inode,
+ const char *fname, const char *fxn, int line);
+extern void __unionfs_check_dentry(const struct dentry *dentry,
+ const char *fname, const char *fxn, int line);
+extern void __unionfs_check_file(const struct file *file,
+ const char *fname, const char *fxn, int line);
+extern void __show_branch_counts(const struct super_block *sb,
+ const char *file, const char *fxn, int line);
+
+#else /* not UNIONFS_DEBUG */
+
+/* we leave useful hooks for these check functions throughout the code */
+#define unionfs_check_inode(i)
+#define unionfs_check_dentry(d)
+#define unionfs_check_file(f)
+#define show_branch_counts(sb)
+
+#endif /* not UNIONFS_DEBUG */
+
#endif /* not _UNION_H_ */
projects / unionfs-3.4.y.git / commitdiff