bool talpa_vfsmount_unlock(unsigned* m_seq)
{
#if defined TALPA_USE_VFSMOUNT_LOCK
# if defined TALPA_VFSMOUNT_LG_BRLOCK
br_read_unlock(&vfsmount_lock);
# elif defined TALPA_VFSMOUNT_LOCK_BRLOCK
br_read_unlock(vfsmount_lock);
# else
spinlock_t* talpa_vfsmount_lock_addr = (spinlock_t *)talpa_get_symbol("vfmount_lock", (void *)TALPA_VFSMOUNT_LOCK_ADDR);
spin_unlock(talpa_vfsmount_lock_addr);
# endif
#elif defined TALPA_USE_MOUNT_LOCK
seqlock_t* mount_lock_addr = (seqlock_t *)talpa_get_symbol("mount_lock", (void *)TALPA_MOUNT_LOCK_ADDR);
if (need_seqretry(mount_lock_addr, *m_seq)) {
*m_seq = 1;
return true;
}
done_seqretry(mount_lock_addr, *m_seq);
#else
// On 2.4 we don't have vfsmount_lock - we use dcache_lock instead
spin_unlock(&dcache_lock);
#endif
return false;
}
static talpa_mount_struct* talpa_lookup_mnt_last(struct vfsmount *mnt, struct dentry *dentry)
{
#ifdef TALPA_HAVE_LOOKUP_MNT_LAST
TALPA_PTR_FIX lookup_mnt_last_func lookup_mnt_last = (lookup_mnt_last_func)talpa_get_symbol("__lookup_mnt_last", (void *)TALPA__LOOKUP_MNT_LAST);
return lookup_mnt_last(mnt, dentry);
#endif
#ifdef TALPA_HAVE_LOOKUP_MNT
TALPA_PTR_FIX lookup_mnt_func lookup_mnt = (lookup_mnt_func)talpa_get_symbol("__lookup_mnt", (void *)TALPA__LOOKUP_MNT);
return lookup_mnt(mnt, dentry, 0);
#endif
return NULL;
}
void talpa_tasklist_unlock(void)
{
rwlock_t* talpa_tasklist_lock_addr = (rwlock_t *)talpa_get_symbol("tasklist_lock", (void *)TALPA_TASKLIST_LOCK_ADDR);
read_unlock(talpa_tasklist_lock_addr);
}
TALPA_FILENAME_T * talpa_getname(const char __user * filename )
{
/*
* Uses putname if available, or final_putname - but they come from the same define
*/
typedef TALPA_FILENAME_T * (*getname_func)(const char __user * filename);
getname_func getname = (getname_func)talpa_get_symbol("getname", (void *)TALPA_GETNAME_ADDRESS);
return(getname(filename));
}
void talpa_putname(TALPA_FILENAME_T* filename)
{
/*
* Uses putname if available, or final_putname - but they come from the same define
*/
typedef void(*putname_func)(TALPA_FILENAME_T *);
putname_func putname = (putname_func)talpa_get_symbol("putname", (void *)TALPA_PUTNAME_ADDRESS);
putname(filename);
}
/*
* hidden vfsmnt_lock handling
*/
void talpa_vfsmount_lock(unsigned* m_seq)
{
#if defined TALPA_USE_VFSMOUNT_LOCK
# if defined TALPA_VFSMOUNT_LG_BRLOCK
br_read_lock(&vfsmount_lock);
# elif defined TALPA_VFSMOUNT_LOCK_BRLOCK
br_read_lock(vfsmount_lock);
# else
spinlock_t* talpa_vfsmount_lock_addr = (spinlock_t *)talpa_get_symbol("vfmount_lock", (void *)TALPA_VFSMOUNT_LOCK_ADDR);
spin_lock(talpa_vfsmount_lock_addr);
# endif
#elif defined TALPA_USE_MOUNT_LOCK
seqlock_t* mount_lock_addr = (seqlock_t *)talpa_get_symbol("mount_lock", (void *)TALPA_MOUNT_LOCK_ADDR);
read_seqbegin_or_lock(mount_lock_addr,m_seq);
#else
// On 2.4 we don't have vfsmount_lock - we use dcache_lock instead
spin_lock(&dcache_lock);
#endif
}
char* talpa__d_path( struct dentry *dentry, struct vfsmount *vfsmnt,
struct dentry *root, struct vfsmount *rootmnt,
char *buffer, int buflen, bool* nonRootNamespaceOut)
{
char* path;
/* Get the function pointer for the real __d_path if we're going to call it. */
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) || (defined TALPA_HAS_DPATH)
# if defined TALPA_DPATH_SLES11
typedef char *(*d_path_func)(const struct path *, struct path *, char *, int, int);
# elif defined TALPA_DPATH_PATH
typedef char *(*d_path_func)(const struct path *, struct path *, char *, int);
# elif defined TALPA_DPATH_SUSE103
typedef char *(*d_path_func)(struct dentry *, struct vfsmount *, struct dentry *, struct vfsmount *, char *buffer, int buflen, int flags);
# else
typedef char *(*d_path_func)(struct dentry *, struct vfsmount *, struct dentry *, struct vfsmount *, char *buffer, int buflen);
# endif
# if defined TALPA_HAS_DPATH_ADDR
d_path_func kernel_d_path = (d_path_func)talpa_get_symbol("__d_path", (void *)TALPA_DPATH_ADDR);
# else
d_path_func kernel_d_path = &__d_path;
# endif
# if defined TALPA_DPATH_SLES11 || defined TALPA_DPATH_PATH
struct path pathPath;
struct path rootPath;
# endif
#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) || (defined TALPA_HAS_DPATH) */
if (nonRootNamespaceOut != NULL)
{
*nonRootNamespaceOut = false;
}
#if defined HOLD_DCACHE_LOCK_WHILE_CALLING_D_PATH
spin_lock(&dcache_lock);
#endif
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) || (defined TALPA_HAS_DPATH)
/* Calling the real __d_path */
# if defined TALPA_DPATH_SLES11 || defined TALPA_DPATH_PATH
pathPath.dentry = dentry;
pathPath.mnt = vfsmnt;
rootPath.dentry = root;
rootPath.mnt = rootmnt;
# endif
# if defined TALPA_D_DNAME_DIRECT_DPATH
if (dentry->d_op && dentry->d_op->d_dname)
{
path = d_path(&pathPath, buffer, buflen);
if ( unlikely( IS_ERR(path) != 0 ) )
{
critical("talpa__d_path: d_path returned an error: %ld",PTR_ERR(path));
path = NULL;
}
if ( NULL != path )
{
return path;
}
}
# endif /* TALPA_D_DNAME_DIRECT_DPATH */
# if defined TALPA_DPATH_SLES11
path = kernel_d_path(&pathPath, &rootPath, buffer, buflen, 0);
# elif defined TALPA_DPATH_PATH
path = kernel_d_path(&pathPath, &rootPath, buffer, buflen);
# elif defined TALPA_DPATH_SUSE103
path = kernel_d_path(dentry, vfsmnt, root, rootmnt, buffer, buflen, 0);
# else
path = kernel_d_path(dentry, vfsmnt, root, rootmnt, buffer, buflen);
# endif
#else
/* Call our own version */
path = __talpa_d_path(dentry, vfsmnt, root, rootmnt, buffer, buflen);
#endif
#if defined HOLD_DCACHE_LOCK_WHILE_CALLING_D_PATH
spin_unlock(&dcache_lock);
#endif
if ( unlikely( IS_ERR(path) != 0 ) )
{
critical("talpa__d_path: kernel__d_path returned an error: %ld",PTR_ERR(path));
path = NULL;
}
else if ( unlikely( NULL == path ) )
{
#ifdef TALPA_D_DNAME_DIRECT_DPATH
/* only use this as a fall-back, it will only return the relative path from a chroot
* Use this in cases where kernel_d_path fails to return a valid path for bind mounts
* in newer kernel in a systemd environment */
path = d_path(&pathPath, buffer, buflen);
if ( unlikely( IS_ERR(path) != 0 ) )
{
critical("talpa__d_path: kernel_d_path returned an error: %ld",PTR_ERR(path));
path = NULL;
}
if (dentry->d_op && dentry->d_op->d_dname)
{
dbg(" dpath=%s",path);
err("dpath=%s - dentry has d_op and d_dname=%p",path,dentry->d_op->d_dname);
}
#endif
if ( NULL == path )
{
if (!IS_ROOT(dentry) && d_unhashed(dentry)) {
dbg("talpa__d_path: kernel_d_path returned NULL for deleted file");
dbg(" basename=%s",dentry->d_name.name);
}
else
{
info("talpa__d_path: kernel_d_path returned NULL for non-deleted file");
info(" basename=%s",dentry->d_name.name);
}
}
else
{
if (!IS_ROOT(dentry) && d_unhashed(dentry))
{
dbg(" talpa__d_path: kernel_d_path returned NULL but d_path returned path %s for deleted file",path);
}
else
{
/* the systemd / containers / bind mount case.
*
* Now so common that we don't want to even debug log it
* dbg(" talpa__d_path: kernel_d_path returned NULL but d_path returned path %s for non-deleted file",path);
*/
#ifdef TALPA_MNT_NAMESPACE
if (NULL != getNamespaceInfo(vfsmnt) && (!S_ISDIR(dentry->d_inode->i_mode)))
{
/* we're in a namespace/container */
if (nonRootNamespaceOut != NULL)
{
*nonRootNamespaceOut = true;
}
}
if (false)
{
debugPathWalk(dentry, vfsmnt, root, rootmnt);
}
#endif
}
}
}
return path;
}
