diff options
Diffstat (limited to 'drivers/visorbus/visorbus_main.c')
| -rw-r--r-- | drivers/visorbus/visorbus_main.c | 1234 |
1 files changed, 0 insertions, 1234 deletions
diff --git a/drivers/visorbus/visorbus_main.c b/drivers/visorbus/visorbus_main.c deleted file mode 100644 index 152fd29f04f2..000000000000 --- a/drivers/visorbus/visorbus_main.c +++ /dev/null @@ -1,1234 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright � 2010 - 2015 UNISYS CORPORATION - * All rights reserved. - */ - -#include <linux/ctype.h> -#include <linux/debugfs.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/visorbus.h> -#include <linux/uuid.h> - -#include "visorbus_private.h" - -static const guid_t visor_vbus_channel_guid = VISOR_VBUS_CHANNEL_GUID; - -/* Display string that is guaranteed to be no longer the 99 characters */ -#define LINESIZE 99 -#define POLLJIFFIES_NORMALCHANNEL 10 - -/* stores whether bus_registration was successful */ -static bool initialized; -static struct dentry *visorbus_debugfs_dir; - -/* - * DEVICE type attributes - * - * The modalias file will contain the guid of the device. - */ -static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct visor_device *vdev; - const guid_t *guid; - - vdev = to_visor_device(dev); - guid = visorchannel_get_guid(vdev->visorchannel); - return sprintf(buf, "visorbus:%pUl\n", guid); -} -static DEVICE_ATTR_RO(modalias); - -static struct attribute *visorbus_dev_attrs[] = { - &dev_attr_modalias.attr, - NULL, -}; - -ATTRIBUTE_GROUPS(visorbus_dev); - -/* filled in with info about parent chipset driver when we register with it */ -static struct visor_vbus_deviceinfo chipset_driverinfo; -/* filled in with info about this driver, wrt it servicing client busses */ -static struct visor_vbus_deviceinfo clientbus_driverinfo; - -/* list of visor_device structs, linked via .list_all */ -static LIST_HEAD(list_all_bus_instances); -/* list of visor_device structs, linked via .list_all */ -static LIST_HEAD(list_all_device_instances); - -/* - * Generic function useful for validating any type of channel when it is - * received by the client that will be accessing the channel. - * Note that <logCtx> is only needed for callers in the EFI environment, and - * is used to pass the EFI_DIAG_CAPTURE_PROTOCOL needed to log messages. - */ -int visor_check_channel(struct channel_header *ch, struct device *dev, - const guid_t *expected_guid, char *chname, - u64 expected_min_bytes, u32 expected_version, - u64 expected_signature) -{ - if (!guid_is_null(expected_guid)) { - /* caller wants us to verify type GUID */ - if (!guid_equal(&ch->chtype, expected_guid)) { - dev_err(dev, "Channel mismatch on channel=%s(%pUL) field=type expected=%pUL actual=%pUL\n", - chname, expected_guid, expected_guid, - &ch->chtype); - return 0; - } - } - /* verify channel size */ - if (expected_min_bytes > 0) { - if (ch->size < expected_min_bytes) { - dev_err(dev, "Channel mismatch on channel=%s(%pUL) field=size expected=0x%-8.8Lx actual=0x%-8.8Lx\n", - chname, expected_guid, - (unsigned long long)expected_min_bytes, - ch->size); - return 0; - } - } - /* verify channel version */ - if (expected_version > 0) { - if (ch->version_id != expected_version) { - dev_err(dev, "Channel mismatch on channel=%s(%pUL) field=version expected=0x%-8.8lx actual=0x%-8.8x\n", - chname, expected_guid, - (unsigned long)expected_version, - ch->version_id); - return 0; - } - } - /* verify channel signature */ - if (expected_signature > 0) { - if (ch->signature != expected_signature) { - dev_err(dev, "Channel mismatch on channel=%s(%pUL) field=signature expected=0x%-8.8Lx actual=0x%-8.8Lx\n", - chname, expected_guid, expected_signature, - ch->signature); - return 0; - } - } - return 1; -} - -static int visorbus_uevent(struct device *xdev, struct kobj_uevent_env *env) -{ - struct visor_device *dev; - const guid_t *guid; - - dev = to_visor_device(xdev); - guid = visorchannel_get_guid(dev->visorchannel); - return add_uevent_var(env, "MODALIAS=visorbus:%pUl", guid); -} - -/* - * visorbus_match() - called automatically upon adding a visor_device - * (device_add), or adding a visor_driver - * (visorbus_register_visor_driver) - * @xdev: struct device for the device being matched - * @xdrv: struct device_driver for driver to match device against - * - * Return: 1 iff the provided driver can control the specified device - */ -static int visorbus_match(struct device *xdev, struct device_driver *xdrv) -{ - const guid_t *channel_type; - int i; - struct visor_device *dev; - struct visor_driver *drv; - struct visorchannel *chan; - - dev = to_visor_device(xdev); - channel_type = visorchannel_get_guid(dev->visorchannel); - drv = to_visor_driver(xdrv); - chan = dev->visorchannel; - if (!drv->channel_types) - return 0; - for (i = 0; !guid_is_null(&drv->channel_types[i].guid); i++) - if (guid_equal(&drv->channel_types[i].guid, channel_type) && - visor_check_channel(visorchannel_get_header(chan), - xdev, - &drv->channel_types[i].guid, - (char *)drv->channel_types[i].name, - drv->channel_types[i].min_bytes, - drv->channel_types[i].version, - VISOR_CHANNEL_SIGNATURE)) - return i + 1; - return 0; -} - -/* - * This describes the TYPE of bus. - * (Don't confuse this with an INSTANCE of the bus.) - */ -static struct bus_type visorbus_type = { - .name = "visorbus", - .match = visorbus_match, - .uevent = visorbus_uevent, - .dev_groups = visorbus_dev_groups, -}; - -struct visor_busdev { - u32 bus_no; - u32 dev_no; -}; - -static int match_visorbus_dev_by_id(struct device *dev, const void *data) -{ - struct visor_device *vdev = to_visor_device(dev); - const struct visor_busdev *id = data; - - if (vdev->chipset_bus_no == id->bus_no && - vdev->chipset_dev_no == id->dev_no) - return 1; - return 0; -} - -struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no, - struct visor_device *from) -{ - struct device *dev; - struct device *dev_start = NULL; - struct visor_busdev id = { - .bus_no = bus_no, - .dev_no = dev_no - }; - - if (from) - dev_start = &from->device; - dev = bus_find_device(&visorbus_type, dev_start, (void *)&id, - match_visorbus_dev_by_id); - if (!dev) - return NULL; - return to_visor_device(dev); -} - -/* - * visorbus_release_busdevice() - called when device_unregister() is called for - * the bus device instance, after all other tasks - * involved with destroying the dev are complete - * @xdev: struct device for the bus being released - */ -static void visorbus_release_busdevice(struct device *xdev) -{ - struct visor_device *dev = dev_get_drvdata(xdev); - - debugfs_remove(dev->debugfs_bus_info); - debugfs_remove_recursive(dev->debugfs_dir); - visorchannel_destroy(dev->visorchannel); - kfree(dev); -} - -/* - * visorbus_release_device() - called when device_unregister() is called for - * each child device instance - * @xdev: struct device for the visor device being released - */ -static void visorbus_release_device(struct device *xdev) -{ - struct visor_device *dev = to_visor_device(xdev); - - visorchannel_destroy(dev->visorchannel); - kfree(dev); -} - -/* - * BUS specific channel attributes to appear under - * /sys/bus/visorbus<x>/dev<y>/channel - */ - -static ssize_t physaddr_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - - return sprintf(buf, "0x%llx\n", - visorchannel_get_physaddr(vdev->visorchannel)); -} -static DEVICE_ATTR_RO(physaddr); - -static ssize_t nbytes_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - - return sprintf(buf, "0x%lx\n", - visorchannel_get_nbytes(vdev->visorchannel)); -} -static DEVICE_ATTR_RO(nbytes); - -static ssize_t clientpartition_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - - return sprintf(buf, "0x%llx\n", - visorchannel_get_clientpartition(vdev->visorchannel)); -} -static DEVICE_ATTR_RO(clientpartition); - -static ssize_t typeguid_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - char typeid[LINESIZE]; - - return sprintf(buf, "%s\n", - visorchannel_id(vdev->visorchannel, typeid)); -} -static DEVICE_ATTR_RO(typeguid); - -static ssize_t zoneguid_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - char zoneid[LINESIZE]; - - return sprintf(buf, "%s\n", - visorchannel_zoneid(vdev->visorchannel, zoneid)); -} -static DEVICE_ATTR_RO(zoneguid); - -static ssize_t typename_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - int i = 0; - struct bus_type *xbus = dev->bus; - struct device_driver *xdrv = dev->driver; - struct visor_driver *drv = NULL; - - if (!xdrv) - return 0; - i = xbus->match(dev, xdrv); - if (!i) - return 0; - drv = to_visor_driver(xdrv); - return sprintf(buf, "%s\n", drv->channel_types[i - 1].name); -} -static DEVICE_ATTR_RO(typename); - -static struct attribute *channel_attrs[] = { - &dev_attr_physaddr.attr, - &dev_attr_nbytes.attr, - &dev_attr_clientpartition.attr, - &dev_attr_typeguid.attr, - &dev_attr_zoneguid.attr, - &dev_attr_typename.attr, - NULL -}; - -ATTRIBUTE_GROUPS(channel); - -/* - * BUS instance attributes - * - * define & implement display of bus attributes under - * /sys/bus/visorbus/devices/visorbus<n>. - */ -static ssize_t partition_handle_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - u64 handle = visorchannel_get_clientpartition(vdev->visorchannel); - - return sprintf(buf, "0x%llx\n", handle); -} -static DEVICE_ATTR_RO(partition_handle); - -static ssize_t partition_guid_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - - return sprintf(buf, "{%pUb}\n", &vdev->partition_guid); -} -static DEVICE_ATTR_RO(partition_guid); - -static ssize_t partition_name_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - - return sprintf(buf, "%s\n", vdev->name); -} -static DEVICE_ATTR_RO(partition_name); - -static ssize_t channel_addr_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - u64 addr = visorchannel_get_physaddr(vdev->visorchannel); - - return sprintf(buf, "0x%llx\n", addr); -} -static DEVICE_ATTR_RO(channel_addr); - -static ssize_t channel_bytes_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - u64 nbytes = visorchannel_get_nbytes(vdev->visorchannel); - - return sprintf(buf, "0x%llx\n", nbytes); -} -static DEVICE_ATTR_RO(channel_bytes); - -static ssize_t channel_id_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct visor_device *vdev = to_visor_device(dev); - int len = 0; - - visorchannel_id(vdev->visorchannel, buf); - len = strlen(buf); - buf[len++] = '\n'; - return len; -} -static DEVICE_ATTR_RO(channel_id); - -static struct attribute *visorbus_attrs[] = { - &dev_attr_partition_handle.attr, - &dev_attr_partition_guid.attr, - &dev_attr_partition_name.attr, - &dev_attr_channel_addr.attr, - &dev_attr_channel_bytes.attr, - &dev_attr_channel_id.attr, - NULL -}; - -ATTRIBUTE_GROUPS(visorbus); - -/* - * BUS debugfs entries - * - * define & implement display of debugfs attributes under - * /sys/kernel/debug/visorbus/visorbus<n>. - */ - -/* - * vbuschannel_print_devinfo() - format a struct visor_vbus_deviceinfo - * and write it to a seq_file - * @devinfo: the struct visor_vbus_deviceinfo to format - * @seq: seq_file to write to - * @devix: the device index to be included in the output data, or -1 if no - * device index is to be included - * - * Reads @devInfo, and writes it in human-readable notation to @seq. - */ -static void vbuschannel_print_devinfo(struct visor_vbus_deviceinfo *devinfo, - struct seq_file *seq, int devix) -{ - /* uninitialized vbus device entry */ - if (!isprint(devinfo->devtype[0])) - return; - if (devix >= 0) - seq_printf(seq, "[%d]", devix); - else - /* vbus device entry is for bus or chipset */ - seq_puts(seq, " "); - /* - * Note: because the s-Par back-end is free to scribble in this area, - * we never assume '\0'-termination. - */ - seq_printf(seq, "%-*.*s ", (int)sizeof(devinfo->devtype), - (int)sizeof(devinfo->devtype), devinfo->devtype); - seq_printf(seq, "%-*.*s ", (int)sizeof(devinfo->drvname), - (int)sizeof(devinfo->drvname), devinfo->drvname); - seq_printf(seq, "%.*s\n", (int)sizeof(devinfo->infostrs), - devinfo->infostrs); -} - -static int bus_info_debugfs_show(struct seq_file *seq, void *v) -{ - int i = 0; - unsigned long off; - struct visor_vbus_deviceinfo dev_info; - struct visor_device *vdev = seq->private; - struct visorchannel *channel = vdev->visorchannel; - - if (!channel) - return 0; - - seq_printf(seq, - "Client device/driver info for %s partition (vbus #%u):\n", - ((vdev->name) ? (char *)(vdev->name) : ""), - vdev->chipset_bus_no); - if (visorchannel_read(channel, - offsetof(struct visor_vbus_channel, chp_info), - &dev_info, sizeof(dev_info)) >= 0) - vbuschannel_print_devinfo(&dev_info, seq, -1); - if (visorchannel_read(channel, - offsetof(struct visor_vbus_channel, bus_info), - &dev_info, sizeof(dev_info)) >= 0) - vbuschannel_print_devinfo(&dev_info, seq, -1); - - off = offsetof(struct visor_vbus_channel, dev_info); - while (off + sizeof(dev_info) <= visorchannel_get_nbytes(channel)) { - if (visorchannel_read(channel, off, &dev_info, - sizeof(dev_info)) >= 0) - vbuschannel_print_devinfo(&dev_info, seq, i); - off += sizeof(dev_info); - i++; - } - return 0; -} - -static int bus_info_debugfs_open(struct inode *inode, struct file *file) -{ - return single_open(file, bus_info_debugfs_show, inode->i_private); -} - -static const struct file_operations bus_info_debugfs_fops = { - .owner = THIS_MODULE, - .open = bus_info_debugfs_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static void dev_periodic_work(struct timer_list *t) -{ - struct visor_device *dev = from_timer(dev, t, timer); - struct visor_driver *drv = to_visor_driver(dev->device.driver); - - drv->channel_interrupt(dev); - mod_timer(&dev->timer, jiffies + POLLJIFFIES_NORMALCHANNEL); -} - -static int dev_start_periodic_work(struct visor_device *dev) -{ - if (dev->being_removed || dev->timer_active) - return -EINVAL; - - /* now up by at least 2 */ - get_device(&dev->device); - dev->timer.expires = jiffies + POLLJIFFIES_NORMALCHANNEL; - add_timer(&dev->timer); - dev->timer_active = true; - return 0; -} - -static void dev_stop_periodic_work(struct visor_device *dev) -{ - if (!dev->timer_active) - return; - - del_timer_sync(&dev->timer); - dev->timer_active = false; - put_device(&dev->device); -} - -/* - * visordriver_remove_device() - handle visor device going away - * @xdev: struct device for the visor device being removed - * - * This is called when device_unregister() is called for each child device - * instance, to notify the appropriate visorbus function driver that the device - * is going away, and to decrease the reference count of the device. - * - * Return: 0 iff successful - */ -static int visordriver_remove_device(struct device *xdev) -{ - struct visor_device *dev = to_visor_device(xdev); - struct visor_driver *drv = to_visor_driver(xdev->driver); - - mutex_lock(&dev->visordriver_callback_lock); - dev->being_removed = true; - drv->remove(dev); - mutex_unlock(&dev->visordriver_callback_lock); - dev_stop_periodic_work(dev); - put_device(&dev->device); - return 0; -} - -/* - * visorbus_unregister_visor_driver() - unregisters the provided driver - * @drv: the driver to unregister - * - * A visor function driver calls this function to unregister the driver, - * i.e., within its module_exit function. - */ -void visorbus_unregister_visor_driver(struct visor_driver *drv) -{ - driver_unregister(&drv->driver); -} -EXPORT_SYMBOL_GPL(visorbus_unregister_visor_driver); - -/* - * visorbus_read_channel() - reads from the designated channel into - * the provided buffer - * @dev: the device whose channel is read from - * @offset: the offset into the channel at which reading starts - * @dest: the destination buffer that is written into from the channel - * @nbytes: the number of bytes to read from the channel - * - * If receiving a message, use the visorchannel_signalremove() function instead. - * - * Return: integer indicating success (zero) or failure (non-zero) - */ -int visorbus_read_channel(struct visor_device *dev, unsigned long offset, - void *dest, unsigned long nbytes) -{ - return visorchannel_read(dev->visorchannel, offset, dest, nbytes); -} -EXPORT_SYMBOL_GPL(visorbus_read_channel); - -/* - * visorbus_write_channel() - writes the provided buffer into the designated - * channel - * @dev: the device whose channel is written to - * @offset: the offset into the channel at which writing starts - * @src: the source buffer that is written into the channel - * @nbytes: the number of bytes to write into the channel - * - * If sending a message, use the visorchannel_signalinsert() function instead. - * - * Return: integer indicating success (zero) or failure (non-zero) - */ -int visorbus_write_channel(struct visor_device *dev, unsigned long offset, - void *src, unsigned long nbytes) -{ - return visorchannel_write(dev->visorchannel, offset, src, nbytes); -} -EXPORT_SYMBOL_GPL(visorbus_write_channel); - -/* - * visorbus_enable_channel_interrupts() - enables interrupts on the - * designated device - * @dev: the device on which to enable interrupts - * - * Currently we don't yet have a real interrupt, so for now we just call the - * interrupt function periodically via a timer. - */ -int visorbus_enable_channel_interrupts(struct visor_device *dev) -{ - struct visor_driver *drv = to_visor_driver(dev->device.driver); - - if (!drv->channel_interrupt) { - dev_err(&dev->device, "%s no interrupt function!\n", __func__); - return -ENOENT; - } - - return dev_start_periodic_work(dev); -} -EXPORT_SYMBOL_GPL(visorbus_enable_channel_interrupts); - -/* - * visorbus_disable_channel_interrupts() - disables interrupts on the - * designated device - * @dev: the device on which to disable interrupts - */ -void visorbus_disable_channel_interrupts(struct visor_device *dev) -{ - dev_stop_periodic_work(dev); -} -EXPORT_SYMBOL_GPL(visorbus_disable_channel_interrupts); - -/* - * create_visor_device() - create visor device as a result of receiving the - * controlvm device_create message for a new device - * @dev: a freshly-zeroed struct visor_device, containing only filled-in values - * for chipset_bus_no and chipset_dev_no, that will be initialized - * - * This is how everything starts from the device end. - * This function is called when a channel first appears via a ControlVM - * message. In response, this function allocates a visor_device to correspond - * to the new channel, and attempts to connect it the appropriate * driver. If - * the appropriate driver is found, the visor_driver.probe() function for that - * driver will be called, and will be passed the new * visor_device that we - * just created. - * - * It's ok if the appropriate driver is not yet loaded, because in that case - * the new device struct will just stick around in the bus' list of devices. - * When the appropriate driver calls visorbus_register_visor_driver(), the - * visor_driver.probe() for the new driver will be called with the new device. - * - * Return: 0 if successful, otherwise the negative value returned by - * device_add() indicating the reason for failure - */ -int create_visor_device(struct visor_device *dev) -{ - int err; - u32 chipset_bus_no = dev->chipset_bus_no; - u32 chipset_dev_no = dev->chipset_dev_no; - - mutex_init(&dev->visordriver_callback_lock); - dev->device.bus = &visorbus_type; - dev->device.groups = channel_groups; - device_initialize(&dev->device); - dev->device.release = visorbus_release_device; - /* keep a reference just for us (now 2) */ - get_device(&dev->device); - timer_setup(&dev->timer, dev_periodic_work, 0); - /* - * bus_id must be a unique name with respect to this bus TYPE (NOT bus - * instance). That's why we need to include the bus number within the - * name. - */ - err = dev_set_name(&dev->device, "vbus%u:dev%u", - chipset_bus_no, chipset_dev_no); - if (err) - goto err_put; - /* - * device_add does this: - * bus_add_device(dev) - * ->device_attach(dev) - * ->for each driver drv registered on the bus that dev is on - * if (dev.drv) ** device already has a driver ** - * ** not sure we could ever get here... ** - * else - * if (bus.match(dev,drv)) [visorbus_match] - * dev.drv = drv - * if (!drv.probe(dev)) [visordriver_probe_device] - * dev.drv = NULL - * - * Note that device_add does NOT fail if no driver failed to claim the - * device. The device will be linked onto bus_type.klist_devices - * regardless (use bus_for_each_dev). - */ - err = device_add(&dev->device); - if (err < 0) - goto err_put; - list_add_tail(&dev->list_all, &list_all_device_instances); - dev->state.created = 1; - visorbus_response(dev, err, CONTROLVM_DEVICE_CREATE); - /* success: reference kept via unmatched get_device() */ - return 0; - -err_put: - put_device(&dev->device); - dev_err(&dev->device, "Creating visor device failed. %d\n", err); - return err; -} - -void remove_visor_device(struct visor_device *dev) -{ - list_del(&dev->list_all); - put_device(&dev->device); - if (dev->pending_msg_hdr) - visorbus_response(dev, 0, CONTROLVM_DEVICE_DESTROY); - device_unregister(&dev->device); -} - -static int get_vbus_header_info(struct visorchannel *chan, - struct device *dev, - struct visor_vbus_headerinfo *hdr_info) -{ - int err; - - if (!visor_check_channel(visorchannel_get_header(chan), - dev, - &visor_vbus_channel_guid, - "vbus", - sizeof(struct visor_vbus_channel), - VISOR_VBUS_CHANNEL_VERSIONID, - VISOR_CHANNEL_SIGNATURE)) - return -EINVAL; - - err = visorchannel_read(chan, sizeof(struct channel_header), hdr_info, - sizeof(*hdr_info)); - if (err < 0) - return err; - if (hdr_info->struct_bytes < sizeof(struct visor_vbus_headerinfo)) - return -EINVAL; - if (hdr_info->device_info_struct_bytes < - sizeof(struct visor_vbus_deviceinfo)) - return -EINVAL; - return 0; -} - -/* - * write_vbus_chp_info() - write the contents of <info> to the struct - * visor_vbus_channel.chp_info - * @chan: indentifies the s-Par channel that will be updated - * @hdr_info: used to find appropriate channel offset to write data - * @info: contains the information to write - * - * Writes chipset info into the channel memory to be used for diagnostic - * purposes. - * - * Returns no value since this is debug information and not needed for - * device functionality. - */ -static void write_vbus_chp_info(struct visorchannel *chan, - struct visor_vbus_headerinfo *hdr_info, - struct visor_vbus_deviceinfo *info) -{ - int off; - - if (hdr_info->chp_info_offset == 0) - return; - - off = sizeof(struct channel_header) + hdr_info->chp_info_offset; - visorchannel_write(chan, off, info, sizeof(*info)); -} - -/* - * write_vbus_bus_info() - write the contents of <info> to the struct - * visor_vbus_channel.bus_info - * @chan: indentifies the s-Par channel that will be updated - * @hdr_info: used to find appropriate channel offset to write data - * @info: contains the information to write - * - * Writes bus info into the channel memory to be used for diagnostic - * purposes. - * - * Returns no value since this is debug information and not needed for - * device functionality. - */ -static void write_vbus_bus_info(struct visorchannel *chan, - struct visor_vbus_headerinfo *hdr_info, - struct visor_vbus_deviceinfo *info) -{ - int off; - - if (hdr_info->bus_info_offset == 0) - return; - - off = sizeof(struct channel_header) + hdr_info->bus_info_offset; - visorchannel_write(chan, off, info, sizeof(*info)); -} - -/* - * write_vbus_dev_info() - write the contents of <info> to the struct - * visor_vbus_channel.dev_info[<devix>] - * @chan: indentifies the s-Par channel that will be updated - * @hdr_info: used to find appropriate channel offset to write data - * @info: contains the information to write - * @devix: the relative device number (0..n-1) of the device on the bus - * - * Writes device info into the channel memory to be used for diagnostic - * purposes. - * - * Returns no value since this is debug information and not needed for - * device functionality. - */ -static void write_vbus_dev_info(struct visorchannel *chan, - struct visor_vbus_headerinfo *hdr_info, - struct visor_vbus_deviceinfo *info, - unsigned int devix) -{ - int off; - - if (hdr_info->dev_info_offset == 0) - return; - off = (sizeof(struct channel_header) + hdr_info->dev_info_offset) + - (hdr_info->device_info_struct_bytes * devix); - visorchannel_write(chan, off, info, sizeof(*info)); -} - -static void bus_device_info_init( - struct visor_vbus_deviceinfo *bus_device_info_ptr, - const char *dev_type, const char *drv_name) -{ - memset(bus_device_info_ptr, 0, sizeof(struct visor_vbus_deviceinfo)); - snprintf(bus_device_info_ptr->devtype, - sizeof(bus_device_info_ptr->devtype), - "%s", (dev_type) ? dev_type : "unknownType"); - snprintf(bus_device_info_ptr->drvname, - sizeof(bus_device_info_ptr->drvname), - "%s", (drv_name) ? drv_name : "unknownDriver"); - snprintf(bus_device_info_ptr->infostrs, - sizeof(bus_device_info_ptr->infostrs), "kernel ver. %s", - utsname()->release); -} - -/* - * publish_vbus_dev_info() - for a child device just created on a client bus, - * fill in information about the driver that is - * controlling this device into the appropriate slot - * within the vbus channel of the bus instance - * @visordev: struct visor_device for the desired device - */ -static void publish_vbus_dev_info(struct visor_device *visordev) -{ - int i; - struct visor_device *bdev; - struct visor_driver *visordrv; - u32 bus_no = visordev->chipset_bus_no; - u32 dev_no = visordev->chipset_dev_no; - struct visor_vbus_deviceinfo dev_info; - const char *chan_type_name = NULL; - struct visor_vbus_headerinfo *hdr_info; - - if (!visordev->device.driver) - return; - bdev = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL); - if (!bdev) - return; - hdr_info = (struct visor_vbus_headerinfo *)bdev->vbus_hdr_info; - if (!hdr_info) - return; - visordrv = to_visor_driver(visordev->device.driver); - - /* - * Within the list of device types (by GUID) that the driver - * says it supports, find out which one of those types matches - * the type of this device, so that we can include the device - * type name - */ - for (i = 0; visordrv->channel_types[i].name; i++) { - if (guid_equal(&visordrv->channel_types[i].guid, - &visordev->channel_type_guid)) { - chan_type_name = visordrv->channel_types[i].name; - break; - } - } - bus_device_info_init(&dev_info, chan_type_name, visordrv->name); - write_vbus_dev_info(bdev->visorchannel, hdr_info, &dev_info, dev_no); - write_vbus_chp_info(bdev->visorchannel, hdr_info, &chipset_driverinfo); - write_vbus_bus_info(bdev->visorchannel, hdr_info, - &clientbus_driverinfo); -} - -/* - * visordriver_probe_device() - handle new visor device coming online - * @xdev: struct device for the visor device being probed - * - * This is called automatically upon adding a visor_device (device_add), or - * adding a visor_driver (visorbus_register_visor_driver), but only after - * visorbus_match() has returned 1 to indicate a successful match between - * driver and device. - * - * If successful, a reference to the device will be held onto via get_device(). - * - * Return: 0 if successful, meaning the function driver's probe() function - * was successful with this device, otherwise a negative errno - * value indicating failure reason - */ -static int visordriver_probe_device(struct device *xdev) -{ - int err; - struct visor_driver *drv = to_visor_driver(xdev->driver); - struct visor_device *dev = to_visor_device(xdev); - - mutex_lock(&dev->visordriver_callback_lock); - dev->being_removed = false; - err = drv->probe(dev); - if (err) { - mutex_unlock(&dev->visordriver_callback_lock); - return err; - } - /* success: reference kept via unmatched get_device() */ - get_device(&dev->device); - publish_vbus_dev_info(dev); - mutex_unlock(&dev->visordriver_callback_lock); - return 0; -} - -/* - * visorbus_register_visor_driver() - registers the provided visor driver for - * handling one or more visor device - * types (channel_types) - * @drv: the driver to register - * - * A visor function driver calls this function to register the driver. The - * caller MUST fill in the following fields within the #drv structure: - * name, version, owner, channel_types, probe, remove - * - * Here's how the whole Linux bus / driver / device model works. - * - * At system start-up, the visorbus kernel module is loaded, which registers - * visorbus_type as a bus type, using bus_register(). - * - * All kernel modules that support particular device types on a - * visorbus bus are loaded. Each of these kernel modules calls - * visorbus_register_visor_driver() in their init functions, passing a - * visor_driver struct. visorbus_register_visor_driver() in turn calls - * register_driver(&visor_driver.driver). This .driver member is - * initialized with generic methods (like probe), whose sole responsibility - * is to act as a broker for the real methods, which are within the - * visor_driver struct. (This is the way the subclass behavior is - * implemented, since visor_driver is essentially a subclass of the - * generic driver.) Whenever a driver_register() happens, core bus code in - * the kernel does (see device_attach() in drivers/base/dd.c): - * - * for each dev associated with the bus (the bus that driver is on) that - * does not yet have a driver - * if bus.match(dev,newdriver) == yes_matched ** .match specified - * ** during bus_register(). - * newdriver.probe(dev) ** for visor drivers, this will call - * ** the generic driver.probe implemented in visorbus.c, - * ** which in turn calls the probe specified within the - * ** struct visor_driver (which was specified by the - * ** actual device driver as part of - * ** visorbus_register_visor_driver()). - * - * The above dance also happens when a new device appears. - * So the question is, how are devices created within the system? - * Basically, just call device_add(dev). See pci_bus_add_devices(). - * pci_scan_device() shows an example of how to build a device struct. It - * returns the newly-created struct to pci_scan_single_device(), who adds it - * to the list of devices at PCIBUS.devices. That list of devices is what - * is traversed by pci_bus_add_devices(). - * - * Return: integer indicating success (zero) or failure (non-zero) - */ -int visorbus_register_visor_driver(struct visor_driver *drv) -{ - /* can't register on a nonexistent bus */ - if (!initialized) - return -ENODEV; - if (!drv->probe) - return -EINVAL; - if (!drv->remove) - return -EINVAL; - if (!drv->pause) - return -EINVAL; - if (!drv->resume) - return -EINVAL; - - drv->driver.name = drv->name; - drv->driver.bus = &visorbus_type; - drv->driver.probe = visordriver_probe_device; - drv->driver.remove = visordriver_remove_device; - drv->driver.owner = drv->owner; - /* - * driver_register does this: - * bus_add_driver(drv) - * ->if (drv.bus) ** (bus_type) ** - * driver_attach(drv) - * for each dev with bus type of drv.bus - * if (!dev.drv) ** no driver assigned yet ** - * if (bus.match(dev,drv)) [visorbus_match] - * dev.drv = drv - * if (!drv.probe(dev)) [visordriver_probe_device] - * dev.drv = NULL - */ - return driver_register(&drv->driver); -} -EXPORT_SYMBOL_GPL(visorbus_register_visor_driver); - -/* - * visorbus_create_instance() - create a device instance for the visorbus itself - * @dev: struct visor_device indicating the bus instance - * - * Return: 0 for success, otherwise negative errno value indicating reason for - * failure - */ -int visorbus_create_instance(struct visor_device *dev) -{ - int id = dev->chipset_bus_no; - int err; - struct visor_vbus_headerinfo *hdr_info; - - hdr_info = kzalloc(sizeof(*hdr_info), GFP_KERNEL); - if (!hdr_info) - return -ENOMEM; - dev_set_name(&dev->device, "visorbus%d", id); - dev->device.bus = &visorbus_type; - dev->device.groups = visorbus_groups; - dev->device.release = visorbus_release_busdevice; - dev->debugfs_dir = debugfs_create_dir(dev_name(&dev->device), - visorbus_debugfs_dir); - dev->debugfs_bus_info = debugfs_create_file("client_bus_info", 0440, - dev->debugfs_dir, dev, - &bus_info_debugfs_fops); - dev_set_drvdata(&dev->device, dev); - err = get_vbus_header_info(dev->visorchannel, &dev->device, hdr_info); - if (err < 0) - goto err_debugfs_dir; - err = device_register(&dev->device); - if (err < 0) - goto err_debugfs_dir; - list_add_tail(&dev->list_all, &list_all_bus_instances); - dev->state.created = 1; - dev->vbus_hdr_info = (void *)hdr_info; - write_vbus_chp_info(dev->visorchannel, hdr_info, &chipset_driverinfo); - write_vbus_bus_info(dev->visorchannel, hdr_info, &clientbus_driverinfo); - visorbus_response(dev, err, CONTROLVM_BUS_CREATE); - return 0; - -err_debugfs_dir: - debugfs_remove_recursive(dev->debugfs_dir); - kfree(hdr_info); - dev_err(&dev->device, "%s failed: %d\n", __func__, err); - return err; -} - -/* - * visorbus_remove_instance() - remove a device instance for the visorbus itself - * @dev: struct visor_device indentifying the bus to remove - */ -void visorbus_remove_instance(struct visor_device *dev) -{ - /* - * Note that this will result in the release method for - * dev->dev being called, which will call - * visorbus_release_busdevice(). This has something to do with - * the put_device() done in device_unregister(), but I have never - * successfully been able to trace thru the code to see where/how - * release() gets called. But I know it does. - */ - kfree(dev->vbus_hdr_info); - list_del(&dev->list_all); - if (dev->pending_msg_hdr) - visorbus_response(dev, 0, CONTROLVM_BUS_DESTROY); - device_unregister(&dev->device); -} - -/* - * remove_all_visor_devices() - remove all child visorbus device instances - */ -static void remove_all_visor_devices(void) -{ - struct list_head *listentry, *listtmp; - - list_for_each_safe(listentry, listtmp, &list_all_device_instances) { - struct visor_device *dev; - - dev = list_entry(listentry, struct visor_device, list_all); - remove_visor_device(dev); - } -} - -/* - * pause_state_change_complete() - the callback function to be called by a - * visorbus function driver when a - * pending "pause device" operation has - * completed - * @dev: struct visor_device identifying the paused device - * @status: 0 iff the pause state change completed successfully, otherwise - * a negative errno value indicating the reason for failure - */ -static void pause_state_change_complete(struct visor_device *dev, int status) -{ - if (!dev->pausing) - return; - - dev->pausing = false; - visorbus_device_changestate_response(dev, status, - segment_state_standby); -} - -/* - * resume_state_change_complete() - the callback function to be called by a - * visorbus function driver when a - * pending "resume device" operation has - * completed - * @dev: struct visor_device identifying the resumed device - * @status: 0 iff the resume state change completed successfully, otherwise - * a negative errno value indicating the reason for failure - */ -static void resume_state_change_complete(struct visor_device *dev, int status) -{ - if (!dev->resuming) - return; - - dev->resuming = false; - /* - * Notify the chipset driver that the resume is complete, - * which will presumably want to send some sort of response to - * the initiator. - */ - visorbus_device_changestate_response(dev, status, - segment_state_running); -} - -/* - * visorchipset_initiate_device_pause_resume() - start a pause or resume - * operation for a visor device - * @dev: struct visor_device identifying the device being paused or resumed - * @is_pause: true to indicate pause operation, false to indicate resume - * - * Tell the subordinate function driver for a specific device to pause - * or resume that device. Success/failure result is returned asynchronously - * via a callback function; see pause_state_change_complete() and - * resume_state_change_complete(). - */ -static int visorchipset_initiate_device_pause_resume(struct visor_device *dev, - bool is_pause) -{ - int err; - struct visor_driver *drv; - - /* If no driver associated with the device nothing to pause/resume */ - if (!dev->device.driver) - return 0; - if (dev->pausing || dev->resuming) - return -EBUSY; - - drv = to_visor_driver(dev->device.driver); - if (is_pause) { - dev->pausing = true; - err = drv->pause(dev, pause_state_change_complete); - } else { - /* - * The vbus_dev_info structure in the channel was been cleared, - * make sure it is valid. - */ - publish_vbus_dev_info(dev); - dev->resuming = true; - err = drv->resume(dev, resume_state_change_complete); - } - return err; -} - -/* - * visorchipset_device_pause() - start a pause operation for a visor device - * @dev_info: struct visor_device identifying the device being paused - * - * Tell the subordinate function driver for a specific device to pause - * that device. Success/failure result is returned asynchronously - * via a callback function; see pause_state_change_complete(). - */ -int visorchipset_device_pause(struct visor_device *dev_info) -{ - int err; - - err = visorchipset_initiate_device_pause_resume(dev_info, true); - if (err < 0) { - dev_info->pausing = false; - return err; - } - return 0; -} - -/* - * visorchipset_device_resume() - start a resume operation for a visor device - * @dev_info: struct visor_device identifying the device being resumed - * - * Tell the subordinate function driver for a specific device to resume - * that device. Success/failure result is returned asynchronously - * via a callback function; see resume_state_change_complete(). - */ -int visorchipset_device_resume(struct visor_device *dev_info) -{ - int err; - - err = visorchipset_initiate_device_pause_resume(dev_info, false); - if (err < 0) { - dev_info->resuming = false; - return err; - } - return 0; -} - -int visorbus_init(void) -{ - int err; - - visorbus_debugfs_dir = debugfs_create_dir("visorbus", NULL); - bus_device_info_init(&clientbus_driverinfo, "clientbus", "visorbus"); - err = bus_register(&visorbus_type); - if (err < 0) - return err; - initialized = true; - bus_device_info_init(&chipset_driverinfo, "chipset", "visorchipset"); - return 0; -} - -void visorbus_exit(void) -{ - struct list_head *listentry, *listtmp; - - remove_all_visor_devices(); - list_for_each_safe(listentry, listtmp, &list_all_bus_instances) { - struct visor_device *dev; - - dev = list_entry(listentry, struct visor_device, list_all); - visorbus_remove_instance(dev); - } - bus_unregister(&visorbus_type); - initialized = false; - debugfs_remove_recursive(visorbus_debugfs_dir); -} |