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* Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds2012-12-201-99/+230
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
| * virtio_console: Add support for remoteproc serialSjur Brændeland2012-12-181-23/+169
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a simple serial connection driver called VIRTIO_ID_RPROC_SERIAL (11) for communicating with a remote processor in an asymmetric multi-processing configuration. This implementation reuses the existing virtio_console implementation, and adds support for DMA allocation of data buffers and disables use of tty console and the virtio control queue. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Merge struct buffer_token into struct port_bufferSjur Brændeland2012-12-181-76/+53
| | | | | | | | | | | | | | | | | | | | | | | | Refactoring the splice functionality by unifying the approach for sending scatter-lists and regular buffers. This simplifies buffer handling and reduces code size. Splice will now allocate a port_buffer and send_buf() and free_buf() can always be used for any buffer. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Free buffers from out-queue upon closesjur.brandeland@stericsson.com2012-12-181-0/+4
| | | | | | | | | | | | | | | | Free pending output buffers from the virtio out-queue when host has acknowledged port_close. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (rebased & cut down)
| * virtio_console: Use kmalloc instead of kzallocSjur Brændeland2012-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | Avoid the more cpu expensive kzalloc when allocating buffers. Originally kzalloc was intended for isolating the guest from the host by not sending random guest data to the host. But device isolation is not yet in place so kzalloc is not really needed. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Free buffer if splice failsSjur Brændeland2012-12-181-0/+2
| | | | | | | | | | | | | | | | Free the allocated scatter list if send_pages fails in function port_splice_write. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0Rusty Russell2012-12-181-5/+5
| | | | | | | | | | | | We simplified virtqueue_add_buf(), make it clear in the callers. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: don't rely on virtqueue_add_buf() returning capacity.Amit Shah2012-12-181-0/+2
| | | | | | | | | | Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | char: remove use of __devinitBill Pemberton2012-11-211-1/+1
|/ | | | | | | | | | | | | | | | CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: Geoff Levand <geoff@infradead.org> Cc: Mattia Dongili <malattia@linux.it> Cc: Amit Shah <amit.shah@redhat.com> Cc: openipmi-developer@lists.sourceforge.net Cc: linuxppc-dev@lists.ozlabs.org Cc: cbe-oss-dev@lists.ozlabs.org Cc: platform-driver-x86@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* virtio: console: fix error handling in init() functionAlexey Khoroshilov2012-09-281-1/+11
| | | | | | | | | | | If register_virtio_driver() fails, virtio-ports class is not destroyed. The patch adds error handling of register_virtio_driver(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio/console: Allocate scatterlist according to the current pipe sizeMasami Hiramatsu2012-09-281-11/+12
| | | | | | | | | | | | | Allocate scatterlist according to the current pipe size. This allows splicing bigger buffer if the pipe size has been changed by fcntl. Changes in v2: - Just a minor fix for avoiding a confliction with previous patch. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio/console: Wait until the port is ready on spliceMasami Hiramatsu2012-09-281-12/+27
| | | | | | | | | Wait if the port is not connected or full on splice like as write is doing. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio/console: Add a failback for unstealable pipe bufferMasami Hiramatsu2012-09-281-3/+25
| | | | | | | | | | | Add a failback memcpy path for unstealable pipe buffer. If buf->ops->steal() fails, virtio-serial tries to copy the page contents to an allocated page, instead of just failing splice(). Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio/console: Add splice_write supportMasami Hiramatsu2012-09-281-8/+128
| | | | | | | | | | | | | | Enable to use splice_write from pipe to virtio-console port. This steals pages from pipe and directly send it to host. Note that this may accelerate only the guest to host path. Changes in v2: - Use GFP_KERNEL instead of GFP_ATOMIC in syscall context function. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: tell host of open ports after resume from s3/s4Amit Shah2012-05-171-0/+7
| | | | | | | | | | | | | | | If a port was open before going into one of the sleep states, the port can continue normal operation after restore. However, the host has to be told that the guest side of the connection is open to restore pre-suspend state. This wasn't noticed so far due to a bug in qemu that was fixed recently (which marked the guest-side connection as always open). CC: stable@vger.kernel.org # Only for 3.3 Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* simple_open: automatically convert to simple_open()Stephen Boyd2012-04-061-7/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* virtio: console: Disable callbacks for virtqueues at start of S4 freezeAmit Shah2012-01-121-0/+8
| | | | | | | | | | | To ensure we don't receive any more interrupts from the host after we enter the freeze function, disable all vq interrupts. There wasn't any problem seen due to this in tests, but applying this patch makes the freeze case more robust. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Add freeze and restore handlers to support S4Amit Shah2012-01-121-0/+58
| | | | | | | | | | | | | | | Remove all vqs and associated buffers in the freeze callback which prepares us to go into hibernation state. On restore, re-create all the vqs and populate the input vqs with buffers to get to the pre-hibernate state. Note: Any outstanding unconsumed buffers are discarded; which means there's a possibility of data loss in case the host or the guest didn't consume any data already present in the vqs. This can be addressed in a later patch series, perhaps in virtio common code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Move vq and vq buf removal into separate functionsAmit Shah2012-01-121-28/+40
| | | | | | | This common code will be shared with the PM freeze function. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: rename virtqueue_add_buf_gfp to virtqueue_add_bufRusty Russell2012-01-121-3/+3
| | | | | | | | | Remove wrapper functions. This makes the allocation type explicit in all callers; I used GPF_KERNEL where it seemed obvious, left it at GFP_ATOMIC otherwise. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de>
* Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds2011-11-071-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
| * drivers/char: Add module.h to those who were using it implicitlyPaul Gortmaker2011-11-011-0/+1
| | | | | | | | | | | | | | | | A pending cleanup will mean that module.h won't be implicitly everywhere anymore. Make sure the modular drivers in char are actually calling out for <module.h> explicitly in advance. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | virtio: console: wait for first console port for early console outputChristian Borntraeger2011-11-021-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On s390 I have seen some random "Warning: unable to open an initial console" boot failure. Turns out that tty_open fails, because the hvc_alloc was not yet done. In former times this could not happen, since the probe function automatically called hvc_alloc. With newer versions (multiport) some host<->guest interaction is required before hvc_alloc is called. This might be too late, especially if an initramfs is involved. Lets use a completion if we have multiport and an early console. [Amit: * Use NULL instead of 0 for pointer comparison * Rename 'port_added' to 'early_console_added' * Re-format, re-word commit message * Rebase patch on top of current queue] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Acked-by: Chrstian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: add port stats for bytes received, sent and discardedAmit Shah2011-11-021-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds port-specific stats for the number of bytes received, sent and discarded. They're exposed via the debugfs interface. This data can be used to check for data loss bugs (or disprove such claims). It can also be used for accounting, if there's such a need. The stats remain valid throughout the lifetime of the port. Unplugging a port will reset the stats. The numbers are not reset across port opens/closes. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: make discard_port_data() use get_inbuf()Amit Shah2011-11-021-10/+5
| | | | | | | | | | | | | | | | | | discard_port_data() used virtqueue_get_buf() directly instead of using get_inbuf(). Fix this, so that we get accounting for all received bytes. This also simplifies the code a lot. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: rename variableAmit Shah2011-11-021-6/+5
| | | | | | | | | | | | 'ret' is a misnomer in discard_port_data() since we don't return the value. Rename it to 'err'. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: make get_inbuf() return port->inbuf if presentAmit Shah2011-11-021-14/+8
| | | | | | | | | | | | | | | | | | | | | | Instead of pulling in a buffer from the vq each time it's called, get_inbuf() now checks if the current active buffer, in port->inbuf is valid. If it is, just returns a pointer to it. This ends up simplifying a lot of code calling get_inbuf() since the check for port->inbuf being valid was done by all the callers. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: Fix return type for get_inbuf()Amit Shah2011-11-021-1/+1
| | | | | | | | | | | | | | | | get_inbuf() returns void *. There's no reason to return void pointers instead of the correct struct port_buffer *. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: Use wait_event_freezable instead of _interruptibleAmit Shah2011-11-021-4/+5
| | | | | | | | | | | | | | | | Get ready to support suspend/resume by using the freezable calls so that blocking read/write syscalls are handled properly across suspend/resume. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: Ignore port name update request if name already setAmit Shah2011-11-021-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't allow port name changes dynamically for a port. So any requests by the host to change the name are ignored. Before this patch, if the hypervisor sent a port name while we had one set already, we would leak memory equivalent to the size of the old name. This scenario wasn't expected so far, but with the suspend-resume support, we'll send the VIRTIO_CONSOLE_PORT_READY message after restore, which can get us into this situation. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: Fix indentationAmit Shah2011-11-021-1/+1
| | | | | | | | | | | | | | | | Convert spaces to tabs and fix indentation for an if statement split into multiple lines. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio-console: Use virtio_config_val() for retrieving configSasha Levin2011-11-021-6/+4
|/ | | | | | | | | | | | | This patch modifies virtio-console to use virtio_config_val() instead of a 'if(virtio_has_feature()) vdev->config->get()' construct to retrieve optional values from the config space. Cc: Amit Shah <amit.shah@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: virtualization@lists.linux-foundation.org Signed-off-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio console: don't manually set or finalize VIRTIO_CONSOLE_F_MULTIPORT.Rusty Russell2011-05-301-5/+0
| | | | | | | | | | That's already been done by the virtio infrastructure before the probe function is called. Reported-by: alexey.kardashevskiy@au1.ibm.com Acked-by: Amit Shah <amit.shah@redhat.com> Tested-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Enable call to hvc_remove() on console port removeAmit Shah2011-04-211-11/+0
| | | | | | | | | | | | | | | | This call was disabled as hot-unplugging one virtconsole port led to another virtconsole port freezing. Upon testing it again, this now works, so enable it. In addition, a bug was found in qemu wherein removing a port of one type caused the guest output from another port to stop working. I doubt it was just this bug that caused it (since disabling the hvc_remove() call did allow other ports to continue working), but since it's all solved now, we're fine with hot-unplugging of virtconsole ports. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Don't access vqs if device was unpluggedAmit Shah2011-03-061-0/+8
| | | | | | | | | | | | | | | | If a virtio-console device gets unplugged while a port is open, a subsequent close() call on the port accesses vqs to free up buffers. This can lead to a crash. The buffers are already freed up as a result of the call to unplug_ports() from virtcons_remove(). The fix is to simply not access vq information if port->portdev is NULL. Reported-by: juzhang <juzhang@redhat.com> CC: stable@kernel.org Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'tty-linus' of ↵Linus Torvalds2011-02-101-0/+1850
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: serial: bfin_5xx: split uart RX lock from uart port lock to avoid deadlock 68360serial: Plumb in rs_360_get_icount() n_gsm: copy mtu over when configuring via ioctl interface virtio: console: Move file back to drivers/char/
| * virtio: console: Move file back to drivers/char/Amit Shah2011-02-031-0/+1838
|/ | | | | | | | | | | | | | | Commit 728674a7e466628df2aeec6d11a2ae1ef968fb67 moved virtio_console.c to drivers/tty/hvc/ under the perception of this being an hvc driver. It was such once, but these days it has generic communication capabilities as well, so move it to drivers/char/. In the future, the hvc part from this file can be split off and moved under drivers/tty/hvc/. Signed-off-by: Amit Shah <amit.shah@redhat.com> CC: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* tty: move hvc drivers to drivers/tty/hvc/Greg Kroah-Hartman2011-01-131-1838/+0
| | | | | | | | | | 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>
* Char: virtio_console, fix memory leakJiri Slaby2010-11-241-28/+9
| | | | | | | | | | | | | Stanse found that in init_vqs, memory is leaked under certain circumstanses (the fail path order is incorrect). Fix that by checking allocations in one turn and free all of them at once if some fails (some may be NULL, but this is OK). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Amit Shah <amit.shah@redhat.com> Cc: virtualization@lists.linux-foundation.org Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Disable lseek(2) for port file operationsAmit Shah2010-10-211-0/+3
| | | | | | | | | | | The ports are char devices; do not have seeking capabilities. Calling nonseekable_open() from the fops_open() call and setting the llseek fops pointer to no_llseek ensures an lseek() call from userspace returns -ESPIPE. Signed-off-by: Amit Shah <amit.shah@redhat.com> CC: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Send SIGIO in case of port unplugAmit Shah2010-10-211-0/+3
| | | | | | | | If a port has registered for SIGIO signals, let the application know that the port is getting unplugged. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Send SIGIO on new data arrival on portsAmit Shah2010-10-211-0/+3
| | | | | | | | Send a SIGIO signal when new data arrives on a port. This is sent only when the process has requested for the signal to be sent using fcntl(). Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Send SIGIO to processes that request it for host eventsAmit Shah2010-10-211-0/+25
| | | | | | | | | | | | | A process can request for SIGIO on host connect / disconnect events using the O_ASYNC file flag using fcntl(). If that's requested, and if the guest-side connection for the port is open, any host-side open/close events for that port will raise a SIGIO. The process can then use poll() within the signal handler to find out which port triggered the signal. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Reference counting portdev structs is not neededAmit Shah2010-10-211-0/+8
| | | | | | | | | | Explain in a comment why there's no need to reference-count the portdev struct: when a device is yanked out, we can't do anything more with it anyway so just give up doing anything more with the data or the vqs and exit cleanly. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Add reference counting for port structAmit Shah2010-10-211-16/+64
| | | | | | | | | | | | | | When a port got hot-unplugged, when a port was open, any file operation after the unplugging resulted in a crash. This is fixed by ref-counting the port structure, and releasing it only when the file is closed. This splits the unplug operation in two parts: first marks the port as unavailable, removes all the buffers in the vqs and removes the port from the per-device list of ports. The second stage, invoked when all references drop to zero, releases the chardev and frees all other memory. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Use cdev_alloc() instead of cdev_init()Amit Shah2010-10-211-7/+13
| | | | | | | | | This moves to using cdev on the heap instead of it being embedded in the ports struct. This helps individual refcounting and will allow us to properly remove cdev structs after hot-unplugs and close operations. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Add a find_port_by_devt() functionAmit Shah2010-10-211-1/+36
| | | | | | | | | | | | To convert to using cdev as a pointer to avoid kref troubles, we have to use a different method to get to a port from an inode than the current container_of method. Add find_port_by_devt() that looks up all portdevs and ports with those portdevs to find the right port. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: Add a list of portdevs that are activeAmit Shah2010-10-211-0/+15
| | | | | | | | The virtio_console.c driver is capable of handling multiple devices at a time. Maintain a list of devices for future traversal. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: open: Use a common path for error handlingAmit Shah2010-10-211-3/+9
| | | | | | | Just re-arrange code for future patches. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: remove_port() should return voidAmit Shah2010-10-211-2/+1
| | | | | | | | When a port is removed, we have to assume the port is gone. So a success/failure return value doesn't make sense. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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