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linux/drivers/virtio/virtio.c

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Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: set device index in common code. Anthony Liguori points out that three different transports use the virtio code, but each one keeps its own counter to set the virtio_device's index field. In theory (though not in current practice) this means that names could be duplicated, and that risk grows as more transports are created. So we move the selection of the unique virtio_device.index into the common code in virtio.c, which has the side-benefit of removing duplicate code. The only complexity is that lguest and S/390 use the index to uniquely identify the device in case of catastrophic failure before register_virtio_device() is called: now we use the offset within the descriptor page as a unique identifier for the printks. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chris Lalancette <clalance@redhat.com> Cc: Anthony Liguori <anthony@codemonkey.ws>
2008-05-30 15:09:42 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: fix format of sysfs driver/vendor files The sysfs files for virtio produce the wrong format and are missing the required newline. The output for virtio bus vendor/device should have the same format as the corresponding entries for PCI devices. Although this technically changes the ABI for sysfs, these files were broken to start with! Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-11-09 22:20:29 -08:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: fix format of sysfs driver/vendor files The sysfs files for virtio produce the wrong format and are missing the required newline. The output for virtio bus vendor/device should have the same format as the corresponding entries for PCI devices. Although this technically changes the ABI for sysfs, these files were broken to start with! Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-11-09 22:20:29 -08:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: fix format of sysfs driver/vendor files The sysfs files for virtio produce the wrong format and are missing the required newline. The output for virtio bus vendor/device should have the same format as the corresponding entries for PCI devices. Although this technically changes the ABI for sysfs, these files were broken to start with! Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-11-09 22:20:29 -08:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
Module autoprobing support for virtio drivers. This adds the logic to convert the virtio ids into module aliases, and includes a modalias entry in sysfs and the env var to make probing work. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-22 11:03:39 +10:00
virtio: expose features in sysfs Each device negotiates feature bits; expose these in sysfs to help diagnostics and debugging. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:37 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
Module autoprobing support for virtio drivers. This adds the logic to convert the virtio ids into module aliases, and includes a modalias entry in sysfs and the env var to make probing work. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-22 11:03:39 +10:00
virtio: expose features in sysfs Each device negotiates feature bits; expose these in sysfs to help diagnostics and debugging. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:37 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: enhance id_matching for virtio drivers This patch allows a virtio driver to use VIRTIO_DEV_ANY_ID for the device id. This will be used by a test module that can be bound to any virtio device. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-05-26 15:46:10 +02:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: fix id_matching for virtio drivers This bug never appeared, since all current virtio drivers use VIRTIO_DEV_ANY_ID for the vendor field. If a real vendor would be used, the check in virtio_id_match is wrong - it returns 0 if id->vendor == dev->id.vendor. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-05-26 15:46:09 +02:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
Module autoprobing support for virtio drivers. This adds the logic to convert the virtio ids into module aliases, and includes a modalias entry in sysfs and the env var to make probing work. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-22 11:03:39 +10:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
virtio: Rename set_features to finalize_features Rather than explicitly handing the features to the lower-level, we just hand the virtio_device and have it set the features. This make it clear that it has the chance to manipulate the features of the device at this point (and that all feature negotiation is already done). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:07 -05:00
virtio: Formally reserve bits 28-31 to be 'transport' features. We assign feature bits as required, but it makes sense to reserve some for the particular transport, rather than the particular device. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:07 -05:00
virtio: meet virtio spec by finalizing features before using device Virtio devices are supposed to negotiate features before they start using the device, but the current code doesn't do this. This is because the driver's probe() function invariably has to add buffers to a virtqueue, or probe the disk (virtio_blk). This currently doesn't matter since no existing backend is strict about the feature negotiation. But it's possible to imagine a future feature which completely changes how a device operates: in this case, we'd need to acknowledge it before using the device. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:35 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: meet virtio spec by finalizing features before using device Virtio devices are supposed to negotiate features before they start using the device, but the current code doesn't do this. This is because the driver's probe() function invariably has to add buffers to a virtqueue, or probe the disk (virtio_blk). This currently doesn't matter since no existing backend is strict about the feature negotiation. But it's possible to imagine a future feature which completely changes how a device operates: in this case, we'd need to acknowledge it before using the device. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:35 -06:00
virtio: Complete feature negotation before updating status lguest (in rusty's use-tun-ringfd patch) assumes that the guest has updated its feature bits before setting its status to VIRTIO_CONFIG_S_DRIVER_OK. That's pretty reasonable, so let's make it so. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-15 23:20:50 +10:00
virtio: meet virtio spec by finalizing features before using device Virtio devices are supposed to negotiate features before they start using the device, but the current code doesn't do this. This is because the driver's probe() function invariably has to add buffers to a virtqueue, or probe the disk (virtio_blk). This currently doesn't matter since no existing backend is strict about the feature negotiation. But it's possible to imagine a future feature which completely changes how a device operates: in this case, we'd need to acknowledge it before using the device. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:35 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: fix module/device unloading The virtio code never hooked through the ->remove callback. Although noone supports device removal at the moment, this code is already needed for module unloading. This of course also revealed bugs in virtio_blk, virtio_net and lguest unloading paths. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-11-19 11:20:42 -05:00
virtio: reset function A reset function solves three problems: 1) It allows us to renegotiate features, eg. if we want to upgrade a guest driver without rebooting the guest. 2) It gives us a clean way of shutting down virtqueues: after a reset, we know that the buffers won't be used by the host, and 3) It helps the guest recover from messed-up drivers. So we remove the ->shutdown hook, and the only way we now remove feature bits is via reset. We leave it to the driver to do the reset before it deletes queues: the balloon driver, for example, needs to chat to the host in its remove function. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:50:03 -05:00
virtio: fix module/device unloading The virtio code never hooked through the ->remove callback. Although noone supports device removal at the moment, this code is already needed for module unloading. This of course also revealed bugs in virtio_blk, virtio_net and lguest unloading paths. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-11-19 11:20:42 -05:00
virtio: Use bus_type probe and remove methods Hook up to the probe() and remove() methods in bus_type rather than device_driver. The latter has been preferred since 2.6.16. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-06-13 13:46:40 +01:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: explicit advertisement of driver features A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: set device index in common code. Anthony Liguori points out that three different transports use the virtio code, but each one keeps its own counter to set the virtio_device's index field. In theory (though not in current practice) this means that names could be duplicated, and that risk grows as more transports are created. So we move the selection of the unique virtio_device.index into the common code in virtio.c, which has the side-benefit of removing duplicate code. The only complexity is that lguest and S/390 use the index to uniquely identify the device in case of catastrophic failure before register_virtio_device() is called: now we use the offset within the descriptor page as a unique identifier for the printks. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chris Lalancette <clalance@redhat.com> Cc: Anthony Liguori <anthony@codemonkey.ws>
2008-05-30 15:09:42 -05:00
virtio: struct device - replace bus_id with dev_name(), dev_set_name() This patch is part of a larger patch series which will remove the "char bus_id[20]" name string from struct device. The device name is managed in the kobject anyway, and without any size limitation, and just needlessly copied into "struct device". To set and read the device name dev_name(dev) and dev_set_name(dev) must be used. If your code uses static kobjects, which it shouldn't do, "const char *init_name" can be used to statically provide the name the registered device should have. At registration time, the init_name field is cleared, to enforce the use of dev_name(dev) to access the device name at a later time. We need to get rid of all occurrences of bus_id in the entire tree to be able to enable the new interface. Please apply this patch, and possibly convert any remaining remaining occurrences of bus_id. We want to submit a patch to -next, which will remove bus_id from "struct device", to find the remaining pieces to convert, and finally switch over to the new api, which will remove the 20 bytes array and does no longer have a size limitation. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:25:56 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: reset function A reset function solves three problems: 1) It allows us to renegotiate features, eg. if we want to upgrade a guest driver without rebooting the guest. 2) It gives us a clean way of shutting down virtqueues: after a reset, we know that the buffers won't be used by the host, and 3) It helps the guest recover from messed-up drivers. So we remove the ->shutdown hook, and the only way we now remove feature bits is via reset. We leave it to the driver to do the reset before it deletes queues: the balloon driver, for example, needs to chat to the host in its remove function. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:50:03 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: add names to virtqueue struct, mapping from devices to queues. Add a linked list of all virtqueues for a virtio device: this helps for debugging and is also needed for upcoming interface change. Also, add a "name" field for clearer debug messages. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:35 -06:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: Allow virtio to be modular and used by modules This is needed for the virtio PCI device to be compiled as a module. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:50:05 -05:00
Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
2007-10-22 11:03:36 +10:00
virtio: Allow virtio to be modular and used by modules This is needed for the virtio PCI device to be compiled as a module. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:50:05 -05:00