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path: root/drivers/tty/hvc/hvc_console.c (follow)
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* tty/hvc_console: Add DTR/RTS callback to handle HUPCL controlHendrik Brueckner2013-07-251-1/+10
| | | | | | | | | | | | | Introduce a new callback to explicitly handle the HUPCL termios control flag. This prepares for a follow-up commit for the hvc_iucv device driver to improve handling when to drop an established network connection. The callback naming is based on the recently added tty_port interface to facilitate a potential refactoring of the hvc_console to use tty_port functions. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: switch tty_flip_buffer_pushJiri Slaby2013-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: switch tty_insert_flip_charJiri Slaby2013-01-161-1/+1
| | | | | | | | | | | | | Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_char is the next one to proceed. This one is used all over the code, so the patch is huge. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: switch tty_buffer_request_room to tty_portJiri Slaby2013-01-161-1/+1
| | | | | | | | | | | | Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty pointer in many call sites. Only tty_port will be needed and hence no more tty_port_tty_get calls in those paths. Here we start with tty_buffer_request_room. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: hvc_console, fix port reference count going to zero prematurelyPaul Mackerras2012-11-141-7/+0
| | | | | | | | | | | | | | | | | | | | Commit bdb498c20040 "TTY: hvc_console, add tty install" took the port refcounting out of hvc_open()/hvc_close(), but failed to remove the kref_put() and tty_kref_put() calls in hvc_hangup() that were there to remove the extra references that hvc_open() had taken. The result was that doing a vhangup() when the current terminal was a hvc_console, then closing the current terminal, would end up calling destroy_hvc_struct() and making the port disappear entirely. This meant that Fedora 17 systems would boot up but then not display the login prompt on the console, and attempts to open /dev/hvc0 would give a "No such device" error. This fixes it by removing the extra kref_put() and tty_kref_put() calls. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'next' of ↵Linus Torvalds2012-10-051-7/+26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc updates from Benjamin Herrenschmidt: "Some highlights in addition to the usual batch of fixes: - 64TB address space support for 64-bit processes by Aneesh Kumar - Gavin Shan did a major cleanup & re-organization of our EEH support code (IBM fancy PCI error handling & recovery infrastructure) which paves the way for supporting different platform backends, along with some rework of the PCIe code for the PowerNV platform in order to remove home made resource allocations and instead use the generic code (which is possible after some small improvements to it done by Gavin). - Uprobes support by Ananth N Mavinakayanahalli - A pile of embedded updates from Freescale folks, including new SoC and board supports, more KVM stuff including preparing for 64-bit BookE KVM support, ePAPR 1.1 updates, etc..." Fixup trivial conflicts in drivers/scsi/ipr.c * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (146 commits) powerpc/iommu: Fix multiple issues with IOMMU pools code powerpc: Fix VMX fix for memcpy case driver/mtd:IFC NAND:Initialise internal SRAM before any write powerpc/fsl-pci: use 'Header Type' to identify PCIE mode powerpc/eeh: Don't release eeh_mutex in eeh_phb_pe_get powerpc: Remove tlb batching hack for nighthawk powerpc: Set paca->data_offset = 0 for boot cpu powerpc/perf: Sample only if SIAR-Valid bit is set in P7+ powerpc/fsl-pci: fix warning when CONFIG_SWIOTLB is disabled powerpc/mpc85xx: Update interrupt handling for IFC controller powerpc/85xx: Enable USB support in p1023rds_defconfig powerpc/smp: Do not disable IPI interrupts during suspend powerpc/eeh: Fix crash on converting OF node to edev powerpc/eeh: Lock module while handling EEH event powerpc/kprobe: Don't emulate store when kprobe stwu r1 powerpc/kprobe: Complete kprobe and migrate exception frame powerpc/kprobe: Introduce a new thread flag powerpc: Remove unused __get_user64() and __put_user64() powerpc/eeh: Global mutex to protect PE tree powerpc/eeh: Remove EEH PE for normal PCI hotplug ...
| * hvc_console: Better kernel console supportBenjamin Herrenschmidt2012-09-051-7/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hvc_console has two methods to instanciate the consoles. hvc_instanciate is meant to be called at early boot, while hvc_alloc is called for more dynamically probed objects. Currently, it only deals with adding kernel consoles in the former case, which means for example that if a console only uses dynamic probing, it will never be usable as a kernel console even when specifying console=hvc0 explicitly, which could be considered annoying... More specifically, on pseries, we only do the early instanciate for the console currently used by the firmware, so if you have your firmware configured to go to a video card, for example, you cannot get your kernel console, oops messages, etc... on your serial port or hypervisor console, which would be handy to deal with oopses. This fixes it by checking if hvc_console.flags & CON_ENABLED is set when registering a new dynamic console, and if not, redo the index check and re-register the console if the index matches, allowing console=hvcN to work. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | tty: Fix hvc returnAlan Cox2012-09-171-1/+1
| | | | | | | | | | | | | | | | HVC returns a size of -1 bytes for the write room in some cases. This is bogus and not handled by the tty layer at all. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | TTY: hvc_console, add tty installJiri Slaby2012-08-141-6/+25
|/ | | | | | | | | | | | | | | This has two outcomes: * we give the TTY layer a tty_port * we do not find the info structure every time open is called on that tty Since we take a reference to a port in ->install, we need also ->cleanup to drop that reference. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: linuxppc-dev@lists.ozlabs.org Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: hvc, fix TTY refcountingJiri Slaby2012-04-131-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A -next commit "TTY: HVC, use tty from tty_port" switched the driver to use tty_port helper for tty refcounting. But it omitted to remove manual tty refcounting from open, close and hangup. So now we are getting random crashes caused by use-after-free: Unable to handle kernel paging request for data at address 0xc0000003f9d550 Faulting instruction address: 0xc0000000001b7f40 Oops: Kernel access of bad area, sig: 11 [#1] ... NIP: c0000000001b7f40 LR: c0000000001b7f14 CTR: c0000000000e04f0 ... NIP [c0000000001b7f40] .__kmalloc+0x70/0x230 LR [c0000000001b7f14] .__kmalloc+0x44/0x230 Call Trace: [c0000003f68bf930] [c0000003f68bf9b0] 0xc0000003f68bf9b0 (unreliable) [c0000003f68bf9e0] [c0000000001e5424] .alloc_fdmem+0x24/0x70 [c0000003f68bfa60] [c0000000001e54f8] .alloc_fdtable+0x88/0x130 [c0000003f68bfaf0] [c0000000001e5924] .dup_fd+0x384/0x450 [c0000003f68bfbd0] [c00000000009a310] .copy_process+0x880/0x11d0 [c0000003f68bfcd0] [c00000000009aee0] .do_fork+0x70/0x400 [c0000003f68bfdc0] [c0000000000141c4] .sys_clone+0x54/0x70 [c0000003f68bfe30] [c000000000009aa0] .ppc_clone+0x8/0xc Fix that by complete removal of tty_kref_get/put in open/close/hangup paths. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-and-tested-by: Michael Neuling <mikey@neuling.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: ppc-dev <linuxppc-dev@lists.ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: HVC, use count from tty_portJiri Slaby2012-04-091-19/+21
| | | | | | | | | | | Now, count is used from tty_port and protected by tty_port->lock. n_outbuf is left unprotected in hvc_hangup now, because there is no point to hold any lock, since other uses are unprotected too. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: HVC, use tty from tty_portJiri Slaby2012-04-091-21/+15
| | | | | | | | | The driver already used refcounting. So we just switch it to tty_port helpers. And switch to tty_port->lock for tty. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: HVC, add tty_portJiri Slaby2012-04-091-9/+14
| | | | | | | | | | And use kref from that. This means we need tty_port->ops->destruct to properly free the structure. This is what destroy_hvc_struct used to do so we leverage that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: remove re-assignments to tty_driver membersJiri Slaby2012-03-081-1/+0
| | | | | | | | | | | | | | All num, magic and owner are set by alloc_tty_driver. No need to re-set them on each allocation site. pti driver sets something different to what it passes to alloc_tty_driver. It is not a bug, since we don't use the lines parameter in any way. Anyway this is fixed, and now we do the right thing. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "hvc_console: display printk messages on console."Linus Torvalds2011-11-071-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 361162459f62dc0826b82c9690a741a940f457f0. It causes an infinite loop when booting Linux under Xen, as so: [ 2.382984] console [hvc0] enabled [ 2.382984] console [hvc0] enabled [ 2.382984] console [hvc0] enabled ... as reported by Konrad Rzeszutek Wilk. And Rusty reports the same for lguest. He goes on to say: "This is not a concurrency problem: the issue seems to be that calling register_console() twice on the same struct console is a bad idea." and Greg says he'll fix it up properly at some point later. Revert for now. Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reported-by: Rusty Russell <rusty@ozlabs.org> Requested-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Miche Baker-Harvey <miche@google.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* hvc_console: display printk messages on console.Miche Baker-Harvey2011-10-181-1/+6
| | | | | | | | | | | | | | printk only works for "registered consoles." Currently, the hvc_console code calls register_console() from hvc_instantiate(), but that's only used in the early console case. In hvc_alloc(), register_console() was not called. Add a call to register_console() in hvc_alloc(), set up the index in the hvc_console, and set up the necessary vtermnos[] and cons_op[] entries so that printk functions work. Signed-off-by: Miche Baker-Harvey <miche@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: use tty_wait_until_sent_from_close in other driversJiri Slaby2011-08-251-1/+1
| | | | | | | | | | | | | | Let's use the newly added helper to avoid stalls in drivers which are not yet ported to tty_port helpers. Those which are broken (call tty_wait_until_sent with irqs disabled) are left untouched. They are in a deeper trouble than we are trying to solve here. This includes amiserial, 68328serial, 68360serial and crisv10. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* hvc_console: Add kdb supportAnton Blanchard2011-07-191-0/+39
| | | | | | | | | | | | | Add poll_get_char and poll_put_char for kdb. Enable kdb at boot with: kgdboc=hvc0 or at runtime with: echo hvc0 > /sys/module/kgdboc/parameters/kgdboc Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* hvc_console: Improve tty/console put_chars handlingHendrik Brueckner2011-07-191-3/+5
| | | | | | | | | | | | | | | | | | | | | | Currently, the hvc_console_print() function drops console output if the hvc backend's put_chars() returns 0. This patch changes this behavior to allow a retry through returning -EAGAIN. This change also affects the hvc_push() function. Both functions are changed to handle -EAGAIN and to retry the put_chars() operation. If a hvc backend returns -EAGAIN, the retry handling differs: - hvc_console_print() spins to write the complete console output. - hvc_push() behaves the same way as for returning 0. Now hvc backends can indirectly control the way how console output is handled through the hvc console layer. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Acked-by: Anton Blanchard <anton@samba.org> Cc: <stable@kernel.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/pseries: Re-implement HVSI as part of hvc_vioBenjamin Herrenschmidt2011-06-291-1/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On pseries machines, consoles are provided by the hypervisor using a low level get_chars/put_chars type interface. However, this is really just a transport to the service processor which implements them either as "raw" console (networked consoles, HMC, ...) or as "hvsi" serial ports. The later is a simple packet protocol on top of the raw character interface that is supposed to convey additional "serial port" style semantics. In practice however, all it does is provide a way to read the CD line and set/clear our DTR line, that's it. We currently implement the "raw" protocol as an hvc console backend (/dev/hvcN) and the "hvsi" protocol using a separate tty driver (/dev/hvsi0). However this is quite impractical. The arbitrary difference between the two type of devices has been a major source of user (and distro) confusion. Additionally, there's an additional mini -hvsi implementation in the pseries platform code for our low level debug console and early boot kernel messages, which means code duplication, though that low level variant is impractical as it's incapable of doing the initial protocol negociation to establish the link to the FSP. This essentially replaces the dedicated hvsi driver and the platform udbg code completely by extending the existing hvc_vio backend used in "raw" mode so that: - It now supports HVSI as well - We add support for hvc backend providing tiocm{get,set} - It also provides a udbg interface for early debug and boot console This is overall less code, though this will only be obvious once we remove the old "hvsi" driver, which is still available for now. When the old driver is enabled, the new code still kicks in for the low level udbg console, replacing the old mini implementation in the platform code, it just doesn't provide the higher level "hvc" interface. In addition to producing generally simler code, this has several benefits over our current situation: - The user/distro only has to deal with /dev/hvcN for the hypervisor console, avoiding all sort of confusion that has plagued us in the past - The tty, kernel and low level debug console all use the same code base which supports the full protocol establishment process, thus the console is now available much earlier than it used to be with the old HVSI driver. The kernel console works much earlier and udbg is available much earlier too. Hackers can enable a hard coded very-early debug console as well that works with HVSI (previously that was only supported for the "raw" mode). I've tried to keep the same semantics as hvsi relative to how I react to things like CD changes, with some subtle differences though: - I clear DTR on close if HUPCL is set - Current hvsi triggers a hangup if it detects a up->down transition on CD (you can still open a console with CD down). My new implementation triggers a hangup if the link to the FSP is severed, and severs it upon detecting a up->down transition on CD. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* tty: move hvc drivers to drivers/tty/hvc/Greg Kroah-Hartman2011-01-131-0/+914
As requested by Arnd Bergmann, the hvc drivers are now moved to the drivers/tty/hvc/ directory. The virtio_console.c driver was also moved, as it required the hvc_console.h file to be able to be built, and it really is a hvc driver. Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>