Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

Changes since v2:
  - v1 dropped lock in vn_lookup, thus assert that vnode_lock is held.

Changes since v3:
  - Fix lock ordering issue in dentry_lookup. The lock respective to the parent
node must be acquired before dentry_lookup and released after the process is
done. Otherwise, a second thread looking up for the same dentry may take the
'NULL' path incorrectly.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

This patch fixes the error codes in four error cases:

1. unlink() of a directory used to return EPERM (as in Posix), and now
   returns EISDIR (as in Linux).

2. rmdir() of a non-empty directory used to return EEXIST (as in Posix)
   and now returns ENOTEMPTY (as in Linux).

3. rmdir() of a regular file (non-directory) used to return EBADF
   and now returns ENOTDIR (as in Linux).

4. readdir() of a regular file (non-directory) used to return EBADF
   and now returns ENOTDIR (as in Linux).

This patch also adds a test, tst-remove.cc, for the various unlink() and
rmdir() success and failure modes.

Fixes #123.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

I tried using a test which called mknod() (to create an empty regular file).
Despite us having an mknod() implementation, it didn't work, and failed on
lookup of the symbol __xmknod.

Turns out that in glibc, mknod() is source-only, and converted to the ABI
function which is __xmknod, whose first parameter is a version number
_MKNOD_VER_LINUX (0 on x86-64 Linux).

So this patch implements __xmknod, and now mknod() works.

Note we already had the same kind of trick for __xstat(), needed so that
stat() would work.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

main.cc was still using tab characters instead of spaces as our coding
conventions dictate. Reindent it, using Eclipse's ctrl-I.
This patch doesn't change anything else.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

This reverts commit e4aad1ba.

It causes tst-vfs.so to just hang.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

  - Drop lock in vn_lookup() and assert that vnode_lock is held.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Everyone is now overriding file's virtual functions; we can make them
pure virtual and remove fileops completely.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Unused.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Derived file objects will be initialized by the class constructor, no need
for fo_init().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Once file::~file() is called, virtual functions no longer dispatch to the
derived type (which has since been destroyed) but to the base type, which
is uninteresting.

Move the call to close() from the destructor to fdrop().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

The default is to dispatch directly to the corresponding member of f_ops,
but that can be overridden.

The fo_*() functions are redirected to dispatch via the virtual functions.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Make sure ZFS intention log is flushed to disk by unmounting rootfs at
poweroff.

Fixes #108.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Make sure the new root vnode is not evicted in vflush() and that we
don't keep reference to the old root dentry in ->m_covered.

Fixes negative dentry count when pivoted root is unmounted.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Add sys_umount2() and implement support for MNT_FORCE that will be used
to force rootfs unmount at poweroff.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Simpler.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

'new file' doesn't return nullptr, it throws (well except in osv where new
always succeeds).

Replace with new (nothrow) to get the expected behaviour.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

They are called at the same time, so make falloc_noinstall() responsible
purely for allocation.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

If we're going to have a vtable in there, the memset() will kill it.

Instead, add initializers for those members not already initialized by
make_file().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

The only caller, soo_close() can only be called from a context where
no file references remain, so no further file API calls can be made.

Remove it.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Subsumed by make_file().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Combines falloc_noinstall() and finit(), which are always used together.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

falloc() is inherently racy in that it installs an uninitialized file
descriptor in a user accessible fd.  It is also hard to use correctly when
an error occurs.  Luckily, we don't use it anywhere, so we can just remove it.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently sys_open() receives an uninitialized file structure from its
callers, which is awkward as the callers must handle opening a file in
two steps.  It also doesn't fit well with C++'s notion of an object being
always fully initialized and valid.

Fix by making sys_open() allocate and return the file structure.  This also
fixes a window in open() where an fd would point to an uninitialized file
(between fdalloc() and sys_open()).

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Needed for C++ conversion.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

In preparation for making 'file' a C++ type.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

When this line is absent in usr.manifest:

  /tmp/index.rb: ../../mgmt/web/views/index.rb

... tst-rename.so test fails with:

  Assertion failed: c_str (<...>/osv/external/misc.bin/usr/
    include/boost/filesystem/path_traits.hpp: dispatch: 214)

The reason for failure is missing /tmp. It is supposed to be created
in unpack_bootfs() but it is later masked by zfs root pivot. The line
in the manifest recreated it, but since mgmt can be a separate module
it may not always be there.

This patch fixes that by adding an explicit entry for /tmp to
usr.manifest, same as we do for /dev.

Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Move runtime creation of '/dev' to image creation to avoid bogus "unable
to create /dev directory" error messages during boot.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Looks like the serial console doesn't display anything
until new line character is received.

Looks like only when '\n' is written to the serial console
QEMU displays the line.

Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

The link system call currently keeps the dentry in the cache by avoiding
calling drele on success.  However, it's not the right thing as link
creates the entry, not references it (much the same as create).
Currently, link works ok, but subsequent calls on the same dentry would
fail as its refcount would be wrong.

Strangely, this problem didn't come up at the time the link syscall was
implemented.  Something that has been changed recently made this bug
manifest.

This patch fixes it.

Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

v2: Check limit of microseconds, among other minor changes (Nadav Har'El, Avi Kivity).
v3: Get rid of goto & label by adding an else clause (Nadav Har'El).

- This patch adds utimes support.
- This patch addresses the issue #93

Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Tested-by: Tomasz Grabiec <tgrabiec@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Attribute flags were moved from 'bsd/sys/cddl/compat/opensolaris/sys/vnode.h'
to 'include/osv/vnode_attr.h'

'bsd/sys/cddl/compat/opensolaris/sys/vnode.h' now includes 'include/osv/vnode_attr.h'
exactly at the place the flags were previously located.

'fs/vfs/vfs.h' includes 'include/osv/vnode_attr.h' as functions that rely on the setattr
feature must specify the flags respective to the attr fields that are going to be changed.

Approach sugested by Nadav Har'El

Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Tested-by: Tomasz Grabiec <tgrabiec@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

To prevent leaks when a file is close()d without an EPOLL_CTL_DEL,
record epoll registrations in the file structure and remove them
when the file is destroyed.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Since it's initialized with the constructor, the mutex is already initialized.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>