The tag enforces a single restriction that all DMA transactions must not
cross a 4GB boundary. Note that while this restriction technically only
applies to PCI-express, this change applies it to all PCI devices as it
is simpler to implement that way and errs on the side of caution.
- Add a softc structure for PCI bus devices to hold the bus_dma tag and
a new pci_attach_common() routine that performs actions common to the
attach phase of all PCI bus drivers. Right now this only consists of
a bootverbose printf and the allocate of a bus_dma tag if necessary.
- Adjust all PCI bus drivers to allocate a PCI bus softc and to call
pci_attach_common() from their attach routines.
MFC after: 2 weeks
associated with the previous vnode (if any) associated with the target of
a rename(). Otherwise, a lookup of the target pathname concurrent with a
rename() could re-add a name cache entry after the namei(RENAME) lookup
in kern_renameat() had purged the target pathname.
MFC after: 2 weeks
syscall. Before r5958, seekdir() was called for its side effect of
freeing memory allocated by opendir() for rewinddir(), but that revision
added _reclaim_telldir() that frees all memory allocated by telldir()
calls, making this call redundant.
This introduces a slight change. If an application duplicated the descriptor
obtained through dirfd(), it can no longer rely on file position to be
reset to the start of file after a call to closedir(). It's believed to
be safe because neither POSIX, nor any other OS I've tested (NetBSD, Linux,
OS X) rewind the file offset pointer on closedir().
Reported by: Igor Sysoev
They were made excessive in r205424 by opening with O_DIRECTORY.
Also eliminated the fcntl() call used to set FD_CLOEXEC by opening
with O_CLOEXEC.
(fdopendir() still checks that the passed descriptor is a directory,
and sets FD_CLOEXEC on it.)
Reviewed by: ed
interface supported by mvs(4) are 88SX, while AHCI-like chips are 88SE.
PR: kern/165271
Submitted by: Jia-Shiun Li <jiashiun@gmail.com>
MFC after: 1 week
The scan code unlocks the comlock and calls into the driver. It then
assumes the state hasn't changed from underneath it.
Although I haven't seen this particular condition trigger, I'd like to
be informed if I or anyone else sees it.
What I'm thinking may occur:
* A cancellation comes in during the scan_end call;
* the cancel flag is set;
* but it's never checked, so scandone isn't updated;
* .. and the interface stays in the STA power save mode.
It's a subtle race, if it even exists.
PR: kern/163318
clients.
These are helful when making certain drivers work on both Linux
and FreeBSD without changing the code flow too much.
Reviewed by: kib, wlosh
MFC after: 1 month
not ACPI-specific at all, but deal with PCI power states. Also,
pci_set_powerstate() fails with EOPNOTSUPP if a request is made that the
underlying device does not support rather than falling back to somehow
setting D0.
pci_cfg_save() and pci_cfg_restore() for device drivers to use when
saving and restoring state (e.g. to handle device-specific resets).
Reviewed by: imp
MFC after: 2 weeks
long for specifying a boundary constraint.
- Change bus_dma tags to use bus_addr_t instead of bus_size_t for boundary
constraints.
These allow boundary constraints to be fully expressed for cases where
sizeof(bus_addr_t) != sizeof(bus_size_t). Specifically, it allows a
driver to properly specify a 4GB boundary in a PAE kernel.
Note that this cannot be safely MFC'd without a lot of compat shims due
to KBI changes, so I do not intend to merge it.
Reviewed by: scottl
snapshots on UFS filesystems running with journaled soft updates.
This is the first of several bugs that need to be fixed before
removing the restriction added in -r230250 to prevent the use
of snapshots on filesystems running with journaled soft updates.
The deadlock occurs when holding the snapshot lock (snaplk)
and then trying to flush an inode via ffs_update(). We become
blocked by another process trying to flush a different inode
contained in the same inode block that we need. It holds the
inode block for which we are waiting locked. When it tries to
write the inode block, it gets blocked waiting for the our
snaplk when it calls ffs_copyonwrite() to see if the inode
block needs to be copied in our snapshot.
The most obvious place that this deadlock arises is in the
ffs_copyonwrite() routine when it updates critical metadata
in a snapshot and tries to write it out before proceeding.
The fix here is to write the data and indirect block pointer
for the snapshot, but to skip the call to ffs_update() to
write the snapshot inode. To ensure that we will never have
to update a pointer in the inode itself, the ffs_snapshot()
routine that creates the snapshot has to ensure that all the
direct blocks are allocated as part of the creation of the
snapshot.
A less obvious place that this deadlock occurs is when we hold
the snaplk because we are deleting a snapshot. In the course of
doing the deletion, we need to allocate various soft update
dependency structures and allocate some journal space. If we
hit a resource limit while doing this we decrease the resources
in use by flushing out an existing dirty file to get it to give
up the soft dependency resources that it holds. The flush can
cause an ffs_update() to be done on the inode for the file that
we have selected to flush resulting in the same deadlock as
described above when the inode that we have chosen to flush
resides in the same inode block as the snapshot inode that we hold.
The fix is to defer cleaning up any time that the inode on which
we are operating is a snapshot.
Help and review by: Jeff Roberson
Tested by: Peter Holm
MFC (to 9 only) after: 2 weeks
installs clang as /usr/bin/cc, /usr/bin/c++ and /usr/bin/cpp.
Note this does *not* disable building and installing gcc, which will
still be available as /usr/bin/gcc, /usr/bin/g++ and /usr/bin/gcpp. If
you want to disable gcc completely, you must use WITHOUT_GCC.
MFC after: 2 weeks
