There is no reason to keep these tightly coupled data structures
separate. Moreover, there is no reason to have a union of file
descriptor and file pointer, since the second can be derived from
the first. The result are somewhat cleaner VFS internals.
Change-Id: I854da7d8291177878eecfc3077ef0a9e0cc82aaa
Commit 723e513 erroneously removed a yield() call from VFS which was
necessary to get resumed pipe read/write threads to run before VFS
blocks on receive(). The removal caused those threads to run only
once VFS received another message, effectively slowing down activity
on pipes to a crawl in some cases.
Instead of readding the yield() call, this patch restructures the
get_work() code to go back through the main message loop even when no
new work is received, thus ensuring that newly started threads are
always activated without requiring a special case.
This fixes#65.
Change-Id: I59b7fb9e403d87dba1a5deecb04539cc37517742
For VFS, initialization is a special case for processing work: PFS
and the ramdisk MFS must be fully mounted before VFS can process any
other requests, in particular from init(8). This case was handled by
receiving reply messages only from the FS service being mounted, but
this effectively disallowed PFS from calling setuid(2) at startup.
This patch lets VFS receive all messages during the mounting process,
but defer processing any new requests. As a result, the FS services
have a bit more freedom in what they can do during startup.
Change-Id: I18275f458952a8d790736a9c9559b27bbef97b7b
This patch fixes two related issues:
- If a large (>PIPE_BUF) pipe write is processed partially, only to be
followed by a write error condition, then the process is left in an
incorrect state, possibly causing VFS to crash on a subsequent call.
- If such a partially processed large pipe write ends up resulting in
an EPIPE error, no corresponding SIGPIPE signal is generated.
The corrected behavior is tested in test68.
Change-Id: I5540e61ab6bcc60a31201485eda04bc49ece2ca8
In order to avoid creating libfsdriver exceptions, two changes to VFS
are necessary:
- the returned position field for reads/writes is no longer abused to
return the new pipe size; VFS is perfectly capable of updating the
size itself;
- during system startup, PFS is now sent a mount request, just like all
other file systems.
In proper "two steps forward, one step back" fashion, the latter point
has the consequence that PFS can no longer drop its privileges at
startup. This is probably best resolved with a more general solution
for all boot image system services. The upside is that PFS no longer
needs to be linked with libc.
Change-Id: I92e2410cdb0d93d0e6107bae10bc08efc2dbb8b3
