Yu Zhao [Mon, 22 Dec 2008 08:54:58 +0000 (16:54 +0800)]
VT-d: fix segment number being ignored when searching DRHD
On platforms with multiple PCI segments, any of the segments can have a DRHD
with INCLUDE_PCI_ALL flag. So need to check the DRHD's segment number against
the PCI device's when searching its DRHD.
Mark McLoughlin [Thu, 20 Nov 2008 14:04:20 +0000 (14:04 +0000)]
intel-iommu: remove some unused struct intel_iommu fields
The seg, saved_msg and sysdev fields appear to be unused since
before the code was first merged.
linux/msi.h is not needed in linux/intel-iommu.h anymore since
there is no longer a reference to struct msi_msg. The MSI code
in drivers/pci/intel-iommu.c still has linux/msi.h included
via linux/dmar.h.
linux/sysdev.h isn't needed because there is no reference to
struct sys_device.
Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Ingo Molnar [Fri, 2 Jan 2009 17:53:14 +0000 (18:53 +0100)]
Disallow gcc versions 3.{0,1}
GCC 3.0 and 3.1 are too old to build a working kernel.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ This check got dropped as obsolete when I simplified the gcc header
inclusion mess in f153b82121b0366fe0e5f9553545cce237335175, but Willy
Tarreau reports actually having those old versions still.. -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 2 Jan 2009 19:44:09 +0000 (11:44 -0800)]
Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
x86: export vector_used_by_percpu_irq
x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
sched: nominate preferred wakeup cpu, fix
x86: fix lguest used_vectors breakage, -v2
x86: fix warning in arch/x86/kernel/io_apic.c
sched: fix warning in kernel/sched.c
sched: move test_sd_parent() to an SMP section of sched.h
sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
sched: activate active load balancing in new idle cpus
sched: bias task wakeups to preferred semi-idle packages
sched: nominate preferred wakeup cpu
sched: favour lower logical cpu number for sched_mc balance
sched: framework for sched_mc/smt_power_savings=N
sched: convert BALANCE_FOR_xx_POWER to inline functions
x86: use possible_cpus=NUM to extend the possible cpus allowed
x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
x86: update io_apic.c to the new cpumask code
x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
x86: xen: use smp_call_function_many()
x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
...
Fixed up trivial conflict in kernel/time/tick-sched.c manually
Linus Torvalds [Fri, 2 Jan 2009 19:41:11 +0000 (11:41 -0800)]
Merge branch 'kvm-updates/2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (140 commits)
KVM: MMU: handle large host sptes on invlpg/resync
KVM: Add locking to virtual i8259 interrupt controller
KVM: MMU: Don't treat a global pte as such if cr4.pge is cleared
MAINTAINERS: Maintainership changes for kvm/ia64
KVM: ia64: Fix kvm_arch_vcpu_ioctl_[gs]et_regs()
KVM: x86: Rework user space NMI injection as KVM_CAP_USER_NMI
KVM: VMX: Fix pending NMI-vs.-IRQ race for user space irqchip
KVM: fix handling of ACK from shared guest IRQ
KVM: MMU: check for present pdptr shadow page in walk_shadow
KVM: Consolidate userspace memory capability reporting into common code
KVM: Advertise the bug in memory region destruction as fixed
KVM: use cpumask_var_t for cpus_hardware_enabled
KVM: use modern cpumask primitives, no cpumask_t on stack
KVM: Extract core of kvm_flush_remote_tlbs/kvm_reload_remote_mmus
KVM: set owner of cpu and vm file operations
anon_inodes: use fops->owner for module refcount
x86: KVM guest: kvm_get_tsc_khz: return khz, not lpj
KVM: MMU: prepopulate the shadow on invlpg
KVM: MMU: skip global pgtables on sync due to cr3 switch
KVM: MMU: collapse remote TLB flushes on root sync
...
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (32 commits)
ide-atapi: start dma in a drive-specific way
ide-atapi: put the rest of non-ide-cd code into the else-clause of ide_transfer_pc
ide-atapi: remove timeout arg to ide_issue_pc
ide-cd: remove handler wrappers
ide-cd: remove xferlen arg to cdrom_start_packet_command
ide-atapi: split drive-specific functionality in ide_issue_pc
ide-atapi: assign expiry and timeout based on device type
ide-atapi: compute cmd_len based on device type in ide_transfer_pc
ide: remove the last ide-scsi remnants
ide-atapi: remove ide-scsi remnants from ide_pc_intr()
ide-atapi: remove ide-scsi remnants from ide_transfer_pc()
ide-atapi: remove ide-scsi remnants from ide_issue_pc
ide-cd: move cdrom_timer_expiry to ide-atapi.c
ide-atapi: teach ide atapi about drive->waiting_for_dma
ide-atapi: accomodate transfer length calculation for ide-cd
ide-atapi: setup dma for ide-cd
ide-atapi: combine drive-specific assignments
ide-atapi: add a dev_is_idecd-inline
remove ide-scsi
ide-floppy: allocate only toplevel packet commands
...
Linus Torvalds [Fri, 2 Jan 2009 18:31:04 +0000 (10:31 -0800)]
Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb
* 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb: (31 commits)
uwb: remove beacon cache entry after calling uwb_notify()
uwb: remove unused include/linux/uwb/debug.h
uwb: use print_hex_dump()
uwb: use dev_dbg() for debug messages
uwb: fix memory leak in uwb_rc_notif()
wusb: fix oops when terminating a non-existant reservation
uwb: fix oops when terminating an already terminated reservation
uwb: improved MAS allocator and reservation conflict handling
wusb: add debug files for ASL, PZL and DI to the whci-hcd driver
uwb: fix oops in debug PAL's reservation callback
uwb: clean up whci_wait_for() timeout error message
wusb: whci-hcd shouldn't do ASL/PZL updates while channel is inactive
uwb: remove unused beacon group join/leave events
wlp: start/stop radio on network interface up/down
uwb: add basic radio manager
uwb: add pal parameter to new reservation callback
uwb: fix races between events and neh timers
uwb: don't unbind the radio controller driver when resetting
uwb: per-radio controller event thread and beacon cache
uwb: add commands to add/remove IEs to the debug interface
...
Federico Heinz [Fri, 2 Jan 2009 16:19:23 +0000 (16:19 +0000)]
i8k: Add Dell Vostro systems
This trivial patch adds support for i8k on the new Dell Vostro models.
I tested it on my Vostro 1400, and it works. It does print a warning
when loading the module:
i8k: unable to get SMM BIOS version
But I couldn't figure out how to fix that. The module seems to work fine,
anyway...
Linus Torvalds [Fri, 2 Jan 2009 18:25:51 +0000 (10:25 -0800)]
Merge branch 'tty-updates' from Alan
* tty-updates: (75 commits)
serial_8250: support for Sealevel Systems Model 7803 COMM+8
hso maintainers update patch
hso modem detect fix patch against Alan Cox'es tty tree
tty: Fix an ircomm warning and note another bug
drivers/char/cyclades.c: cy_pci_probe: fix error path
Serial: UART driver changes for Cavium OCTEON.
Serial: Allow port type to be specified when calling serial8250_register_port.
8250: Serial driver changes to support future Cavium OCTEON serial patches.
8250: Don't clobber spinlocks.
fix for tty-serial-move-port
tty: We want the port object to be persistent
__FUNCTION__ is gcc-specific, use __func__
serial: RS485 ioctl structure uses __u32 include linux/types.h
tty: Drop the lock_kernel in the private ioctl hook
synclink_cs: Convert to tty_port
tty: use port methods for the rocket driver
tty: kref the rocket driver
tty: make rocketport use standard port->flags
tty: Redo the rocket driver locking
tty: Make epca use the port helpers
...
hso modem detect fix patch against Alan Cox'es tty tree
Fixed incorrect check for the modem port, this prevents
crashes caused by issueing a tiocmget_submit_urb
on endpoints which don't exist for non modem devices.
Signed-off-by: Denis Joseph Barrow <D.Barow@option.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Daney [Fri, 2 Jan 2009 13:50:00 +0000 (13:50 +0000)]
Serial: UART driver changes for Cavium OCTEON.
Cavium UART implementation is not covered by existing uart_configS.
Define a new uart_config (PORT_OCTEON) which is specified by OCTEON
platform device registration code.
Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Daney [Fri, 2 Jan 2009 13:49:54 +0000 (13:49 +0000)]
Serial: Allow port type to be specified when calling serial8250_register_port.
Add flag value UPF_FIXED_TYPE which specifies that the UART type is
known and should not be probed. For this case the UARTs properties
are just copied out of the uart_config entry.
This allows us to keep SOC specific 8250 probe code out of 8250.c. In
this case we know the serial hardware will not be changing as it is on
the same silicon as the CPU, and we can specify it with certainty in
the board/cpu setup code.
The alternative is to load up 8250.c with a bunch of OCTEON specific
special cases in the probing code.
Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Daney [Fri, 2 Jan 2009 13:49:47 +0000 (13:49 +0000)]
8250: Serial driver changes to support future Cavium OCTEON serial patches.
In order to use Cavium OCTEON specific serial i/o drivers, we first
patch the 8250 driver to use replaceable I/O functions. Compatible
I/O functions are added for existing iotypeS.
An added benefit of this change is that it makes it easy to factor
some of the existing special cases out to board/SOC specific support
code.
The alternative is to load up 8250.c with a bunch of OCTEON specific
iotype code and bug work-arounds.
Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Daney [Fri, 2 Jan 2009 13:49:41 +0000 (13:49 +0000)]
8250: Don't clobber spinlocks.
In serial8250_isa_init_ports(), the port's lock is initialized. We
should not overwrite it. In early_serial_setup(), only copy in the
fields we need. Since the early console code only uses a subset of
the fields, these are sufficient.
Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:49:21 +0000 (13:49 +0000)]
tty: We want the port object to be persistent
Move the tty_port and uart_info bits around a little. By embedding the uart_info
into the uart_port we get rid of lots of corner case testing and also get the
ability to go port<->state<->info which is a bit more elegant than the current
data structures.
Downsides - we allocate a tiny bit more memory for unused ports, upside we've
removed as much code as it saved for most users..
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tty: Cris has a nice RS485 ioctl so we should steal it
This structure uses the __u32 types for some of its members, which leads
to the following compile error:
$ cc -I.../include -c X.c
In file included from X.c:2: .../include/linux/serial.h:185:
error: expected specifier-qualifier-list before ‘__u32’
$
It seems that these types are appropriate for this structure as it is
to be exposed to userspace. These types are available via linux/types.h
so move the include of that outside the __KERNEL__ section.
Signed-off-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Makes TIOCM ioctls for Data Carrier Detect & related functions
work like /drivers/serial/serial-core.c potentially needed
for pppd & similar user programs.
Signed-off-by: Denis Joseph Barrow <D.Barow@option.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:47:45 +0000 (13:47 +0000)]
tty: Fix the HSO termios handling a bit
Init the tty structure once
Don't set ->low_latency twice in a row
Don't force bits we should be leaving to the user
Don't allocate termios arrays as these are in fact allocated by the tty layer
for you and just overwrite the ones allocated in the driver
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:47:39 +0000 (13:47 +0000)]
hso: net driver using tty without locking
Checking tty == NULL doesn't help us unless we have a clear semantic for
the locking of the tty object in the driver. Use the tty kref objects so that
we can take references to the tty in the USB event handling paths.
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Pfaff [Fri, 2 Jan 2009 13:47:13 +0000 (13:47 +0000)]
tty: N_TTY SIGIO only works for read
The N_TTY ldisc layer does not send SIGIO POLL_OUTs correctly when output is
possible due to flawed handling of the TTY_DO_WRITE_WAKEUP bit. It will
either send no SIGIOs at all or on every tty wakeup.
The fix is to set the bit when the tty driver write would block and test
and clear it on write wakeup.
[Merged with existing N_TTY patches and a small buglet fixed -- Alan]
Signed-off-by: Thomas Pfaff <tpfaff@pcs.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:47:06 +0000 (13:47 +0000)]
tty: USB tty devices can block in tcdrain when unplugged
The underlying problem is that the device methods don't all correctly
handle disconnected status and some keep reporting bytes pending which
causes tcdrain to stall.
When the cable is unplugged they are definitely gone, and as this is true
for all USB cables we can fix it in the core usb serial code.
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Niels de Vos [Fri, 2 Jan 2009 13:46:58 +0000 (13:46 +0000)]
serial: set correct baud_base for Oxford Semiconductor Ltd EXSYS EX-41092 Dual 16950 Serial adapter
The PCI-card identified as "Oxford Semiconductor Ltd EXSYS EX-41092 Dual
16950 Serial adapter" is only usable with other devices (i.e. not the same
card) after doing a "setserial /dev/ttyS<n> baud_base 115200". This
baud_base should be default for this card.
Signed-off-by: Niels de Vos <niels.devos@wincor-nixdorf.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:45:36 +0000 (13:45 +0000)]
tty: relock generic_serial
Switch generic_serial to do port count locking via the tty_port structure
ready for moving to a common port wait routine. Keep the old driver lock for
internal calling so we don't risk messing up the drivers below until we
are ready.
Still needs kref conversions
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:45:26 +0000 (13:45 +0000)]
isicom: redo locking to use tty port locks
This helps set the basis for moving block_til_ready into common code. We also
introduce a tty_port_hangup helper as this will also be generally needed.
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Fri, 2 Jan 2009 13:44:49 +0000 (13:44 +0000)]
CRED: Wrap task credential accesses in the devpts filesystem
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Russell King [Fri, 2 Jan 2009 13:44:27 +0000 (13:44 +0000)]
And here's a patch (to be applied on top of the last) which prevents
this happening again by making use of 'const'.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Russell King [Fri, 2 Jan 2009 13:44:20 +0000 (13:44 +0000)]
Convert the oxsemi tornado special cases to use the quirk interface and not
scribble on its own reference structures.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Fri, 2 Jan 2009 13:44:04 +0000 (13:44 +0000)]
tty: Fix close races in USB serial
USB serial has always had races where the tty port usage count can hit zero
during a receive event. The internal locking is a mutex so we can't use
that in the IRQ handlers.
With krefs we can tackle this differently but we still need to be careful.
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Peterson [Fri, 2 Jan 2009 13:43:40 +0000 (13:43 +0000)]
n_tty: Output bells immediately on a full buffer
This patch causes "bell" (^G) characters (invoked when the input buffer
is full) to be immediately output rather than filling the echo buffer.
This is especially a problem when the tty is stopped and buffers fill, since
the bells do not serve their purpose of immediate notification that the
buffer cannot take further input, and they will flush all at once when the
tty is restarted.
Signed-off-by: Joe Peterson <joe@skyrush.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Peterson [Fri, 2 Jan 2009 13:43:32 +0000 (13:43 +0000)]
n_tty: Fix hanfling of buffer full corner cases
Fix the handling of input characters when the tty buffer is full or nearly
full. This includes tests that are done in n_tty_receive_char() and handling
of PARMRK.
Problems with the buffer-full tests done in receive_char() caused characters to
be lost at times when the buffer(s) filled. Also, these full conditions
would often only be detected with echo on, and PARMRK was not accounted for
properly in all cases. One symptom of these problems, in addition to lost
characters, was early termination from unix commands like tr and cat when
^Q was used to break from a stopped tty with full buffers (note that breaking
out was often previously not possible, due to the pty getting in "gridlock",
which will be addressed in another patch). Note space is always reserved
at the end of the buffer for a newline (or EOF/EOL) in canonical mode.
Signed-off-by: Joe Peterson <joe@skyrush.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Peterson [Fri, 2 Jan 2009 13:43:25 +0000 (13:43 +0000)]
n_tty: Fix handling of control characters and continuations
Fix process_output_block to detect continuation characters correctly
and to handle control characters even when O_OLCUC is enabled. Make
similar change to do_output_char().
Signed-off-by: Joe Peterson <joe@skyrush.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To support containers, allow multiple instances of devpts filesystem, such
that indices of ptys allocated in one instance are independent of ptys
allocated in other instances of devpts.
But to preserve backward compatibility, enable this support for multiple
instances only if:
- CONFIG_DEVPTS_MULTIPLE_INSTANCES is set to Y, and
- '-o newinstance' mount option is specified while mounting devpts
To use multi-instance mount, a container startup script could:
where 'ns_exec -cm /bin/bash' is calls clone() with CLONE_NEWNS flag and execs
/bin/bash in the child process. A pty created by the sshd is not visible in
the original mount of /dev/pts.
USER-SPACE-IMPACT:
- See Documentation/fs/devpts.txt (included in next patch) for user-
space impact in multi-instance and mixed-mode operation.
TODO:
- Update mount(8), pts(4) man pages. Highlight impact of not
redirecting /dev/ptmx to /dev/pts/ptmx after a multi-instance mount.
Changelog[v6]:
- [Dave Hansen] Use new get_init_pts_sb() interface
- [Serge Hallyn] Don't bother displaying 'newinstance' in show_options
- [Serge Hallyn] Use macros (PARSE_REMOUNT/PARSE_MOUNT) instead of 0/1.
- [Serge Hallyn] Check error return from get_sb_single() (now
get_init_pts_sb())
- devpts_pty_kill(): don't dput error dentries
Changelog[v5]:
- Move get_sb_ref() definition to earlier patch
- Move usage info to Documentation/filesystems/devpts.txt (next patch)
- Make ptmx node even in init_pts_ns, now that default mode is 0000
(defined in earlier patch, enabled here).
- Cache ptmx dentry and use to update mode during remount
(defined in earlier patch, enabled here).
- Bugfix: explicitly ignore newinstance on remount (if newinstance was
specified on remount of initial mount, it would be ignored but
/proc/mounts would imply that the option was set)
Changelog[v4]:
- Update patch description to address H. Peter Anvin's comments
- Consolidate multi-instance mode code under new config token,
CONFIG_DEVPTS_MULTIPLE_INSTANCE.
- Move usage-details from patch description to
Documentation/fs/devpts.txt
Changelog[v3]:
- Rename new mount option to 'newinstance'
- Create ptmx nodes only in 'newinstance' mounts
- Bugfix: parse_mount_options() modifies @data but since we need to
parse the @data twice (once in devpts_get_sb() and once during
do_remount_sb()), parse a local copy of @data in devpts_get_sb().
(restructured code in devpts_get_sb() to fix this)
Changelog[v2]:
- Support both single-mount and multiple-mount semantics and
provide '-onewmnt' option to select the semantics.
/dev/ptmx is closely tied to the devpts filesystem. An open of /dev/ptmx,
allocates the next pty index and the associated device shows up in the
devpts fs as /dev/pts/n.
Wih multiple instancs of devpts filesystem, during an open of /dev/ptmx
we would be unable to determine which instance of the devpts is being
accessed.
So we move the 'ptmx' node into /dev/pts and use the inode of the 'ptmx'
node to identify the superblock and hence the devpts instance. This patch
adds ability for the kernel to internally create the [ptmx, c, 5:2] device
when mounting devpts filesystem. Since the ptmx node in devpts is new and
may surprise some userspace scripts, the default permissions for the new
node is 0000. These permissions can be changed either using chmod or by
remounting with the new '-o ptmxmode=0666' mount option.
Changelog[v5]:
- [Serge Hallyn bugfix]: Letting new_inode() assign inode number to
ptmx can collide with hand-assigning inode numbers to ptys. So,
hand-assign specific inode number to ptmx node also.
- [Serge Hallyn]: Maybe safer to grab root dentry mutex while creating
ptmx node
- [Bugfix with Serge Hallyn] Replace lookup_one_len() in mknod_ptmx()
wih d_alloc_name() (lookup during ->get_sb() locks up system). To
simplify patchset, fold the ptmx_dentry patch into this.
Changelog[v4]:
- Change default permissions of pts/ptmx node to 0000.
- Move code for ptmxmode under #ifdef CONFIG_DEVPTS_MULTIPLE_INSTANCES.
Changelog[v3]:
- Rename ptmx_mode to ptmxmode (for consistency with 'newinstance')
Changelog[v2]:
- [H. Peter Anvin] Remove mknod() system call support and create the
ptmx node internally.
Changelog[v1]:
- Earlier version of this patch enabled creating /dev/pts/tty as
well. As pointed out by Al Viro and H. Peter Anvin, that is not
really necessary.
With support for multiple mounts of devpts, the 'config' structure really
represents per-mount options rather than config parameters. Rename 'config'
structure to 'pts_mount_opts' and store it in the super-block.
To enable multiple mounts of devpts, 'allocated_ptys' must be a per-mount
variable rather than a global variable. Move 'allocated_ptys' into the
super_block's s_fs_info.
Changelog[v2]:
Define and use DEVPTS_SB() wrapper.
Remove the 'devpts_root' global variable and find the root dentry using
the super_block. The super-block can be found from the device inode, using
the new wrapper, pts_sb_from_inode().
Changelog: This patch is based on an earlier patchset from Serge Hallyn
and Matt Helsley.
Joe Peterson [Fri, 2 Jan 2009 13:40:53 +0000 (13:40 +0000)]
n_tty: Fix loss of echoed characters and remove bkl from n_tty
Fixes the loss of echoed (and other ldisc-generated characters) when
the tty is stopped or when the driver output buffer is full (happens
frequently for input during continuous program output, such as ^C)
and removes the Big Kernel Lock from the N_TTY line discipline.
Adds an "echo buffer" to the N_TTY line discipline that handles all
ldisc-generated output (including echoed characters). Along with the
loss of characters, this also fixes the associated loss of sync between
tty output and the ldisc state when characters cannot be immediately
written to the tty driver.
The echo buffer stores (in addition to characters) state operations that need
to be done at the time of character output (like management of the column
position). This allows echo to cooperate correctly with program output,
since the ldisc state remains consistent with actual characters written.
Since the echo buffer code now isolates the tty column state code
to the process_out* and process_echoes functions, we can remove the
Big Kernel Lock (BKL) and replace it with mutex locks.
Highlights are:
* Handles echo (and other ldisc output) when tty driver buffer is full
- continuous program output can block echo
* Saves echo when tty is in stopped state (e.g. ^S)
- (e.g.: ^Q will correctly cause held characters to be released for output)
* Control character pairs (e.g. "^C") are treated atomically and not
split up by interleaved program output
* Line discipline state is kept consistent with characters sent to
the tty driver
* Remove the big kernel lock (BKL) from N_TTY line discipline
Signed-off-by: Joe Peterson <joe@skyrush.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / mirror_ubuntu-eoan-kernel.git / log