diff options
Diffstat (limited to 'arch/powerpc/kernel/vio.c')
| -rw-r--r-- | arch/powerpc/kernel/vio.c | 1033 |
1 files changed, 1027 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c index b77f8af7ddd..22a3c33fd75 100644 --- a/arch/powerpc/kernel/vio.c +++ b/arch/powerpc/kernel/vio.c @@ -1,11 +1,12 @@ /* * IBM PowerPC Virtual I/O Infrastructure Support. * - * Copyright (c) 2003-2005 IBM Corp. + * Copyright (c) 2003,2008 IBM Corp. * Dave Engebretsen engebret@us.ibm.com * Santiago Leon santil@us.ibm.com * Hollis Blanchard <hollisb@us.ibm.com> * Stephen Rothwell + * Robert Jennings <rcjenn@us.ibm.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -46,6 +47,996 @@ static struct vio_dev vio_bus_device = { /* fake "parent" device */ .dev.bus = &vio_bus_type, }; +#ifdef CONFIG_PPC_SMLPAR +/** + * vio_cmo_pool - A pool of IO memory for CMO use + * + * @size: The size of the pool in bytes + * @free: The amount of free memory in the pool + */ +struct vio_cmo_pool { + size_t size; + size_t free; +}; + +/* How many ms to delay queued balance work */ +#define VIO_CMO_BALANCE_DELAY 100 + +/* Portion out IO memory to CMO devices by this chunk size */ +#define VIO_CMO_BALANCE_CHUNK 131072 + +/** + * vio_cmo_dev_entry - A device that is CMO-enabled and requires entitlement + * + * @vio_dev: struct vio_dev pointer + * @list: pointer to other devices on bus that are being tracked + */ +struct vio_cmo_dev_entry { + struct vio_dev *viodev; + struct list_head list; +}; + +/** + * vio_cmo - VIO bus accounting structure for CMO entitlement + * + * @lock: spinlock for entire structure + * @balance_q: work queue for balancing system entitlement + * @device_list: list of CMO-enabled devices requiring entitlement + * @entitled: total system entitlement in bytes + * @reserve: pool of memory from which devices reserve entitlement, incl. spare + * @excess: pool of excess entitlement not needed for device reserves or spare + * @spare: IO memory for device hotplug functionality + * @min: minimum necessary for system operation + * @desired: desired memory for system operation + * @curr: bytes currently allocated + * @high: high water mark for IO data usage + */ +struct vio_cmo { + spinlock_t lock; + struct delayed_work balance_q; + struct list_head device_list; + size_t entitled; + struct vio_cmo_pool reserve; + struct vio_cmo_pool excess; + size_t spare; + size_t min; + size_t desired; + size_t curr; + size_t high; +} vio_cmo; + +/** + * vio_cmo_OF_devices - Count the number of OF devices that have DMA windows + */ +static int vio_cmo_num_OF_devs(void) +{ + struct device_node *node_vroot; + int count = 0; + + /* + * Count the number of vdevice entries with an + * ibm,my-dma-window OF property + */ + node_vroot = of_find_node_by_name(NULL, "vdevice"); + if (node_vroot) { + struct device_node *of_node; + struct property *prop; + + for_each_child_of_node(node_vroot, of_node) { + prop = of_find_property(of_node, "ibm,my-dma-window", + NULL); + if (prop) + count++; + } + } + of_node_put(node_vroot); + return count; +} + +/** + * vio_cmo_alloc - allocate IO memory for CMO-enable devices + * + * @viodev: VIO device requesting IO memory + * @size: size of allocation requested + * + * Allocations come from memory reserved for the devices and any excess + * IO memory available to all devices. The spare pool used to service + * hotplug must be equal to %VIO_CMO_MIN_ENT for the excess pool to be + * made available. + * + * Return codes: + * 0 for successful allocation and -ENOMEM for a failure + */ +static inline int vio_cmo_alloc(struct vio_dev *viodev, size_t size) +{ + unsigned long flags; + size_t reserve_free = 0; + size_t excess_free = 0; + int ret = -ENOMEM; + + spin_lock_irqsave(&vio_cmo.lock, flags); + + /* Determine the amount of free entitlement available in reserve */ + if (viodev->cmo.entitled > viodev->cmo.allocated) + reserve_free = viodev->cmo.entitled - viodev->cmo.allocated; + + /* If spare is not fulfilled, the excess pool can not be used. */ + if (vio_cmo.spare >= VIO_CMO_MIN_ENT) + excess_free = vio_cmo.excess.free; + + /* The request can be satisfied */ + if ((reserve_free + excess_free) >= size) { + vio_cmo.curr += size; + if (vio_cmo.curr > vio_cmo.high) + vio_cmo.high = vio_cmo.curr; + viodev->cmo.allocated += size; + size -= min(reserve_free, size); + vio_cmo.excess.free -= size; + ret = 0; + } + + spin_unlock_irqrestore(&vio_cmo.lock, flags); + return ret; +} + +/** + * vio_cmo_dealloc - deallocate IO memory from CMO-enable devices + * @viodev: VIO device freeing IO memory + * @size: size of deallocation + * + * IO memory is freed by the device back to the correct memory pools. + * The spare pool is replenished first from either memory pool, then + * the reserve pool is used to reduce device entitlement, the excess + * pool is used to increase the reserve pool toward the desired entitlement + * target, and then the remaining memory is returned to the pools. + * + */ +static inline void vio_cmo_dealloc(struct vio_dev *viodev, size_t size) +{ + unsigned long flags; + size_t spare_needed = 0; + size_t excess_freed = 0; + size_t reserve_freed = size; + size_t tmp; + int balance = 0; + + spin_lock_irqsave(&vio_cmo.lock, flags); + vio_cmo.curr -= size; + + /* Amount of memory freed from the excess pool */ + if (viodev->cmo.allocated > viodev->cmo.entitled) { + excess_freed = min(reserve_freed, (viodev->cmo.allocated - + viodev->cmo.entitled)); + reserve_freed -= excess_freed; + } + + /* Remove allocation from device */ + viodev->cmo.allocated -= (reserve_freed + excess_freed); + + /* Spare is a subset of the reserve pool, replenish it first. */ + spare_needed = VIO_CMO_MIN_ENT - vio_cmo.spare; + + /* + * Replenish the spare in the reserve pool from the excess pool. + * This moves entitlement into the reserve pool. + */ + if (spare_needed && excess_freed) { + tmp = min(excess_freed, spare_needed); + vio_cmo.excess.size -= tmp; + vio_cmo.reserve.size += tmp; + vio_cmo.spare += tmp; + excess_freed -= tmp; + spare_needed -= tmp; + balance = 1; + } + + /* + * Replenish the spare in the reserve pool from the reserve pool. + * This removes entitlement from the device down to VIO_CMO_MIN_ENT, + * if needed, and gives it to the spare pool. The amount of used + * memory in this pool does not change. + */ + if (spare_needed && reserve_freed) { + tmp = min(spare_needed, min(reserve_freed, + (viodev->cmo.entitled - + VIO_CMO_MIN_ENT))); + + vio_cmo.spare += tmp; + viodev->cmo.entitled -= tmp; + reserve_freed -= tmp; + spare_needed -= tmp; + balance = 1; + } + + /* + * Increase the reserve pool until the desired allocation is met. + * Move an allocation freed from the excess pool into the reserve + * pool and schedule a balance operation. + */ + if (excess_freed && (vio_cmo.desired > vio_cmo.reserve.size)) { + tmp = min(excess_freed, (vio_cmo.desired - vio_cmo.reserve.size)); + + vio_cmo.excess.size -= tmp; + vio_cmo.reserve.size += tmp; + excess_freed -= tmp; + balance = 1; + } + + /* Return memory from the excess pool to that pool */ + if (excess_freed) + vio_cmo.excess.free += excess_freed; + + if (balance) + schedule_delayed_work(&vio_cmo.balance_q, VIO_CMO_BALANCE_DELAY); + spin_unlock_irqrestore(&vio_cmo.lock, flags); +} + +/** + * vio_cmo_entitlement_update - Manage system entitlement changes + * + * @new_entitlement: new system entitlement to attempt to accommodate + * + * Increases in entitlement will be used to fulfill the spare entitlement + * and the rest is given to the excess pool. Decreases, if they are + * possible, come from the excess pool and from unused device entitlement + * + * Returns: 0 on success, -ENOMEM when change can not be made + */ +int vio_cmo_entitlement_update(size_t new_entitlement) +{ + struct vio_dev *viodev; + struct vio_cmo_dev_entry *dev_ent; + unsigned long flags; + size_t avail, delta, tmp; + + spin_lock_irqsave(&vio_cmo.lock, flags); + + /* Entitlement increases */ + if (new_entitlement > vio_cmo.entitled) { + delta = new_entitlement - vio_cmo.entitled; + + /* Fulfill spare allocation */ + if (vio_cmo.spare < VIO_CMO_MIN_ENT) { + tmp = min(delta, (VIO_CMO_MIN_ENT - vio_cmo.spare)); + vio_cmo.spare += tmp; + vio_cmo.reserve.size += tmp; + delta -= tmp; + } + + /* Remaining new allocation goes to the excess pool */ + vio_cmo.entitled += delta; + vio_cmo.excess.size += delta; + vio_cmo.excess.free += delta; + + goto out; + } + + /* Entitlement decreases */ + delta = vio_cmo.entitled - new_entitlement; + avail = vio_cmo.excess.free; + + /* + * Need to check how much unused entitlement each device can + * sacrifice to fulfill entitlement change. + */ + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) { + if (avail >= delta) + break; + + viodev = dev_ent->viodev; + if ((viodev->cmo.entitled > viodev->cmo.allocated) && + (viodev->cmo.entitled > VIO_CMO_MIN_ENT)) + avail += viodev->cmo.entitled - + max_t(size_t, viodev->cmo.allocated, + VIO_CMO_MIN_ENT); + } + + if (delta <= avail) { + vio_cmo.entitled -= delta; + + /* Take entitlement from the excess pool first */ + tmp = min(vio_cmo.excess.free, delta); + vio_cmo.excess.size -= tmp; + vio_cmo.excess.free -= tmp; + delta -= tmp; + + /* + * Remove all but VIO_CMO_MIN_ENT bytes from devices + * until entitlement change is served + */ + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) { + if (!delta) + break; + + viodev = dev_ent->viodev; + tmp = 0; + if ((viodev->cmo.entitled > viodev->cmo.allocated) && + (viodev->cmo.entitled > VIO_CMO_MIN_ENT)) + tmp = viodev->cmo.entitled - + max_t(size_t, viodev->cmo.allocated, + VIO_CMO_MIN_ENT); + viodev->cmo.entitled -= min(tmp, delta); + delta -= min(tmp, delta); + } + } else { + spin_unlock_irqrestore(&vio_cmo.lock, flags); + return -ENOMEM; + } + +out: + schedule_delayed_work(&vio_cmo.balance_q, 0); + spin_unlock_irqrestore(&vio_cmo.lock, flags); + return 0; +} + +/** + * vio_cmo_balance - Balance entitlement among devices + * + * @work: work queue structure for this operation + * + * Any system entitlement above the minimum needed for devices, or + * already allocated to devices, can be distributed to the devices. + * The list of devices is iterated through to recalculate the desired + * entitlement level and to determine how much entitlement above the + * minimum entitlement is allocated to devices. + * + * Small chunks of the available entitlement are given to devices until + * their requirements are fulfilled or there is no entitlement left to give. + * Upon completion sizes of the reserve and excess pools are calculated. + * + * The system minimum entitlement level is also recalculated here. + * Entitlement will be reserved for devices even after vio_bus_remove to + * accommodate reloading the driver. The OF tree is walked to count the + * number of devices present and this will remove entitlement for devices + * that have actually left the system after having vio_bus_remove called. + */ +static void vio_cmo_balance(struct work_struct *work) +{ + struct vio_cmo *cmo; + struct vio_dev *viodev; + struct vio_cmo_dev_entry *dev_ent; + unsigned long flags; + size_t avail = 0, level, chunk, need; + int devcount = 0, fulfilled; + + cmo = container_of(work, struct vio_cmo, balance_q.work); + + spin_lock_irqsave(&vio_cmo.lock, flags); + + /* Calculate minimum entitlement and fulfill spare */ + cmo->min = vio_cmo_num_OF_devs() * VIO_CMO_MIN_ENT; + BUG_ON(cmo->min > cmo->entitled); + cmo->spare = min_t(size_t, VIO_CMO_MIN_ENT, (cmo->entitled - cmo->min)); + cmo->min += cmo->spare; + cmo->desired = cmo->min; + + /* + * Determine how much entitlement is available and reset device + * entitlements + */ + avail = cmo->entitled - cmo->spare; + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) { + viodev = dev_ent->viodev; + devcount++; + viodev->cmo.entitled = VIO_CMO_MIN_ENT; + cmo->desired += (viodev->cmo.desired - VIO_CMO_MIN_ENT); + avail -= max_t(size_t, viodev->cmo.allocated, VIO_CMO_MIN_ENT); + } + + /* + * Having provided each device with the minimum entitlement, loop + * over the devices portioning out the remaining entitlement + * until there is nothing left. + */ + level = VIO_CMO_MIN_ENT; + while (avail) { + fulfilled = 0; + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) { + viodev = dev_ent->viodev; + + if (viodev->cmo.desired <= level) { + fulfilled++; + continue; + } + + /* + * Give the device up to VIO_CMO_BALANCE_CHUNK + * bytes of entitlement, but do not exceed the + * desired level of entitlement for the device. + */ + chunk = min_t(size_t, avail, VIO_CMO_BALANCE_CHUNK); + chunk = min(chunk, (viodev->cmo.desired - + viodev->cmo.entitled)); + viodev->cmo.entitled += chunk; + + /* + * If the memory for this entitlement increase was + * already allocated to the device it does not come + * from the available pool being portioned out. + */ + need = max(viodev->cmo.allocated, viodev->cmo.entitled)- + max(viodev->cmo.allocated, level); + avail -= need; + + } + if (fulfilled == devcount) + break; + level += VIO_CMO_BALANCE_CHUNK; + } + + /* Calculate new reserve and excess pool sizes */ + cmo->reserve.size = cmo->min; + cmo->excess.free = 0; + cmo->excess.size = 0; + need = 0; + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) { + viodev = dev_ent->viodev; + /* Calculated reserve size above the minimum entitlement */ + if (viodev->cmo.entitled) + cmo->reserve.size += (viodev->cmo.entitled - + VIO_CMO_MIN_ENT); + /* Calculated used excess entitlement */ + if (viodev->cmo.allocated > viodev->cmo.entitled) + need += viodev->cmo.allocated - viodev->cmo.entitled; + } + cmo->excess.size = cmo->entitled - cmo->reserve.size; + cmo->excess.free = cmo->excess.size - need; + + cancel_delayed_work(container_of(work, struct delayed_work, work)); + spin_unlock_irqrestore(&vio_cmo.lock, flags); +} + +static void *vio_dma_iommu_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag) +{ + struct vio_dev *viodev = to_vio_dev(dev); + void *ret; + + if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE))) { + atomic_inc(&viodev->cmo.allocs_failed); + return NULL; + } + + ret = dma_iommu_ops.alloc_coherent(dev, size, dma_handle, flag); + if (unlikely(ret == NULL)) { + vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE)); + atomic_inc(&viodev->cmo.allocs_failed); + } + + return ret; +} + +static void vio_dma_iommu_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle) +{ + struct vio_dev *viodev = to_vio_dev(dev); + + dma_iommu_ops.free_coherent(dev, size, vaddr, dma_handle); + + vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE)); +} + +static dma_addr_t vio_dma_iommu_map_single(struct device *dev, void *vaddr, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct vio_dev *viodev = to_vio_dev(dev); + dma_addr_t ret = DMA_ERROR_CODE; + + if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE))) { + atomic_inc(&viodev->cmo.allocs_failed); + return ret; + } + + ret = dma_iommu_ops.map_single(dev, vaddr, size, direction, attrs); + if (unlikely(dma_mapping_error(dev, ret))) { + vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE)); + atomic_inc(&viodev->cmo.allocs_failed); + } + + return ret; +} + +static void vio_dma_iommu_unmap_single(struct device *dev, + dma_addr_t dma_handle, size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct vio_dev *viodev = to_vio_dev(dev); + + dma_iommu_ops.unmap_single(dev, dma_handle, size, direction, attrs); + + vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE)); +} + +static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, + int nelems, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct vio_dev *viodev = to_vio_dev(dev); + struct scatterlist *sgl; + int ret, count = 0; + size_t alloc_size = 0; + + for (sgl = sglist; count < nelems; count++, sgl++) + alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE); + + if (vio_cmo_alloc(viodev, alloc_size)) { + atomic_inc(&viodev->cmo.allocs_failed); + return 0; + } + + ret = dma_iommu_ops.map_sg(dev, sglist, nelems, direction, attrs); + + if (unlikely(!ret)) { + vio_cmo_dealloc(viodev, alloc_size); + atomic_inc(&viodev->cmo.allocs_failed); + } + + for (sgl = sglist, count = 0; count < ret; count++, sgl++) + alloc_size -= roundup(sgl->dma_length, IOMMU_PAGE_SIZE); + if (alloc_size) + vio_cmo_dealloc(viodev, alloc_size); + + return ret; +} + +static void vio_dma_iommu_unmap_sg(struct device *dev, + struct scatterlist *sglist, int nelems, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct vio_dev *viodev = to_vio_dev(dev); + struct scatterlist *sgl; + size_t alloc_size = 0; + int count = 0; + + for (sgl = sglist; count < nelems; count++, sgl++) + alloc_size += roundup(sgl->dma_length, IOMMU_PAGE_SIZE); + + dma_iommu_ops.unmap_sg(dev, sglist, nelems, direction, attrs); + + vio_cmo_dealloc(viodev, alloc_size); +} + +struct dma_mapping_ops vio_dma_mapping_ops = { + .alloc_coherent = vio_dma_iommu_alloc_coherent, + .free_coherent = vio_dma_iommu_free_coherent, + .map_single = vio_dma_iommu_map_single, + .unmap_single = vio_dma_iommu_unmap_single, + .map_sg = vio_dma_iommu_map_sg, + .unmap_sg = vio_dma_iommu_unmap_sg, +}; + +/** + * vio_cmo_set_dev_desired - Set desired entitlement for a device + * + * @viodev: struct vio_dev for device to alter + * @new_desired: new desired entitlement level in bytes + * + * For use by devices to request a change to their entitlement at runtime or + * through sysfs. The desired entitlement level is changed and a balancing + * of system resources is scheduled to run in the future. + */ +void vio_cmo_set_dev_desired(struct vio_dev *viodev, size_t desired) +{ + unsigned long flags; + struct vio_cmo_dev_entry *dev_ent; + int found = 0; + + if (!firmware_has_feature(FW_FEATURE_CMO)) + return; + + spin_lock_irqsave(&vio_cmo.lock, flags); + if (desired < VIO_CMO_MIN_ENT) + desired = VIO_CMO_MIN_ENT; + + /* + * Changes will not be made for devices not in the device list. + * If it is not in the device list, then no driver is loaded + * for the device and it can not receive entitlement. + */ + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) + if (viodev == dev_ent->viodev) { + found = 1; + break; + } + if (!found) + return; + + /* Increase/decrease in desired device entitlement */ + if (desired >= viodev->cmo.desired) { + /* Just bump the bus and device values prior to a balance*/ + vio_cmo.desired += desired - viodev->cmo.desired; + viodev->cmo.desired = desired; + } else { + /* Decrease bus and device values for desired entitlement */ + vio_cmo.desired -= viodev->cmo.desired - desired; + viodev->cmo.desired = desired; + /* + * If less entitlement is desired than current entitlement, move + * any reserve memory in the change region to the excess pool. + */ + if (viodev->cmo.entitled > desired) { + vio_cmo.reserve.size -= viodev->cmo.entitled - desired; + vio_cmo.excess.size += viodev->cmo.entitled - desired; + /* + * If entitlement moving from the reserve pool to the + * excess pool is currently unused, add to the excess + * free counter. + */ + if (viodev->cmo.allocated < viodev->cmo.entitled) + vio_cmo.excess.free += viodev->cmo.entitled - + max(viodev->cmo.allocated, desired); + viodev->cmo.entitled = desired; + } + } + schedule_delayed_work(&vio_cmo.balance_q, 0); + spin_unlock_irqrestore(&vio_cmo.lock, flags); +} + +/** + * vio_cmo_bus_probe - Handle CMO specific bus probe activities + * + * @viodev - Pointer to struct vio_dev for device + * + * Determine the devices IO memory entitlement needs, attempting + * to satisfy the system minimum entitlement at first and scheduling + * a balance operation to take care of the rest at a later time. + * + * Returns: 0 on success, -EINVAL when device doesn't support CMO, and + * -ENOMEM when entitlement is not available for device or + * device entry. + * + */ +static int vio_cmo_bus_probe(struct vio_dev *viodev) +{ + struct vio_cmo_dev_entry *dev_ent; + struct device *dev = &viodev->dev; + struct vio_driver *viodrv = to_vio_driver(dev->driver); + unsigned long flags; + size_t size; + + /* + * Check to see that device has a DMA window and configure + * entitlement for the device. + */ + if (of_get_property(viodev->dev.archdata.of_node, + "ibm,my-dma-window", NULL)) { + /* Check that the driver is CMO enabled and get desired DMA */ + if (!viodrv->get_desired_dma) { + dev_err(dev, "%s: device driver does not support CMO\n", + __func__); + return -EINVAL; + } + + viodev->cmo.desired = IOMMU_PAGE_ALIGN(viodrv->get_desired_dma(viodev)); + if (viodev->cmo.desired < VIO_CMO_MIN_ENT) + viodev->cmo.desired = VIO_CMO_MIN_ENT; + size = VIO_CMO_MIN_ENT; + + dev_ent = kmalloc(sizeof(struct vio_cmo_dev_entry), + GFP_KERNEL); + if (!dev_ent) + return -ENOMEM; + + dev_ent->viodev = viodev; + spin_lock_irqsave(&vio_cmo.lock, flags); + list_add(&dev_ent->list, &vio_cmo.device_list); + } else { + viodev->cmo.desired = 0; + size = 0; + spin_lock_irqsave(&vio_cmo.lock, flags); + } + + /* + * If the needs for vio_cmo.min have not changed since they + * were last set, the number of devices in the OF tree has + * been constant and the IO memory for this is already in + * the reserve pool. + */ + if (vio_cmo.min == ((vio_cmo_num_OF_devs() + 1) * + VIO_CMO_MIN_ENT)) { + /* Updated desired entitlement if device requires it */ + if (size) + vio_cmo.desired += (viodev->cmo.desired - + VIO_CMO_MIN_ENT); + } else { + size_t tmp; + + tmp = vio_cmo.spare + vio_cmo.excess.free; + if (tmp < size) { + dev_err(dev, "%s: insufficient free " + "entitlement to add device. " + "Need %lu, have %lu\n", __func__, + size, (vio_cmo.spare + tmp)); + spin_unlock_irqrestore(&vio_cmo.lock, flags); + return -ENOMEM; + } + + /* Use excess pool first to fulfill request */ + tmp = min(size, vio_cmo.excess.free); + vio_cmo.excess.free -= tmp; + vio_cmo.excess.size -= tmp; + vio_cmo.reserve.size += tmp; + + /* Use spare if excess pool was insufficient */ + vio_cmo.spare -= size - tmp; + + /* Update bus accounting */ + vio_cmo.min += size; + vio_cmo.desired += viodev->cmo.desired; + } + spin_unlock_irqrestore(&vio_cmo.lock, flags); + return 0; +} + +/** + * vio_cmo_bus_remove - Handle CMO specific bus removal activities + * + * @viodev - Pointer to struct vio_dev for device + * + * Remove the device from the cmo device list. The minimum entitlement + * will be reserved for the device as long as it is in the system. The + * rest of the entitlement the device had been allocated will be returned + * to the system. + */ +static void vio_cmo_bus_remove(struct vio_dev *viodev) +{ + struct vio_cmo_dev_entry *dev_ent; + unsigned long flags; + size_t tmp; + + spin_lock_irqsave(&vio_cmo.lock, flags); + if (viodev->cmo.allocated) { + dev_err(&viodev->dev, "%s: device had %lu bytes of IO " + "allocated after remove operation.\n", + __func__, viodev->cmo.allocated); + BUG(); + } + + /* + * Remove the device from the device list being maintained for + * CMO enabled devices. + */ + list_for_each_entry(dev_ent, &vio_cmo.device_list, list) + if (viodev == dev_ent->viodev) { + list_del(&dev_ent->list); + kfree(dev_ent); + break; + } + + /* + * Devices may not require any entitlement and they do not need + * to be processed. Otherwise, return the device's entitlement + * back to the pools. + */ + if (viodev->cmo.entitled) { + /* + * This device has not yet left the OF tree, it's + * minimum entitlement remains in vio_cmo.min and + * vio_cmo.desired + */ + vio_cmo.desired -= (viodev->cmo.desired - VIO_CMO_MIN_ENT); + + /* + * Save min allocation for device in reserve as long + * as it exists in OF tree as determined by later + * balance operation + */ + viodev->cmo.entitled -= VIO_CMO_MIN_ENT; + + /* Replenish spare from freed reserve pool */ + if (viodev->cmo.entitled && (vio_cmo.spare < VIO_CMO_MIN_ENT)) { + tmp = min(viodev->cmo.entitled, (VIO_CMO_MIN_ENT - + vio_cmo.spare)); + vio_cmo.spare += tmp; + viodev->cmo.entitled -= tmp; + } + + /* Remaining reserve goes to excess pool */ + vio_cmo.excess.size += viodev->cmo.entitled; + vio_cmo.excess.free += viodev->cmo.entitled; + vio_cmo.reserve.size -= viodev->cmo.entitled; + + /* + * Until the device is removed it will keep a + * minimum entitlement; this will guarantee that + * a module unload/load will result in a success. + */ + viodev->cmo.entitled = VIO_CMO_MIN_ENT; + viodev->cmo.desired = VIO_CMO_MIN_ENT; + atomic_set(&viodev->cmo.allocs_failed, 0); + } + + spin_unlock_irqrestore(&vio_cmo.lock, flags); +} + +static void vio_cmo_set_dma_ops(struct vio_dev *viodev) +{ + vio_dma_mapping_ops.dma_supported = dma_iommu_ops.dma_supported; + viodev->dev.archdata.dma_ops = &vio_dma_mapping_ops; +} + +/** + * vio_cmo_bus_init - CMO entitlement initialization at bus init time + * + * Set up the reserve and excess entitlement pools based on available + * system entitlement and the number of devices in the OF tree that + * require entitlement in the reserve pool. + */ +static void vio_cmo_bus_init(void) +{ + struct hvcall_mpp_data mpp_data; + int err; + + memset(&vio_cmo, 0, sizeof(struct vio_cmo)); + spin_lock_init(&vio_cmo.lock); + INIT_LIST_HEAD(&vio_cmo.device_list); + INIT_DELAYED_WORK(&vio_cmo.balance_q, vio_cmo_balance); + + /* Get current system entitlement */ + err = h_get_mpp(&mpp_data); + + /* + * On failure, continue with entitlement set to 0, will panic() + * later when spare is reserved. + */ + if (err != H_SUCCESS) { + printk(KERN_ERR "%s: unable to determine system IO "\ + "entitlement. (%d)\n", __func__, err); + vio_cmo.entitled = 0; + } else { + vio_cmo.entitled = mpp_data.entitled_mem; + } + + /* Set reservation and check against entitlement */ + vio_cmo.spare = VIO_CMO_MIN_ENT; + vio_cmo.reserve.size = vio_cmo.spare; + vio_cmo.reserve.size += (vio_cmo_num_OF_devs() * + VIO_CMO_MIN_ENT); + if (vio_cmo.reserve.size > vio_cmo.entitled) { + printk(KERN_ERR "%s: insufficient system entitlement\n", + __func__); + panic("%s: Insufficient system entitlement", __func__); + } + + /* Set the remaining accounting variables */ + vio_cmo.excess.size = vio_cmo.entitled - vio_cmo.reserve.size; + vio_cmo.excess.free = vio_cmo.excess.size; + vio_cmo.min = vio_cmo.reserve.size; + vio_cmo.desired = vio_cmo.reserve.size; +} + +/* sysfs device functions and data structures for CMO */ + +#define viodev_cmo_rd_attr(name) \ +static ssize_t viodev_cmo_##name##_show(struct device *dev, \ + struct device_attribute *attr, \ + char *buf) \ +{ \ + return sprintf(buf, "%lu\n", to_vio_dev(dev)->cmo.name); \ +} + +static ssize_t viodev_cmo_allocs_failed_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct vio_dev *viodev = to_vio_dev(dev); + return sprintf(buf, "%d\n", atomic_read(&viodev->cmo.allocs_failed)); +} + +static ssize_t viodev_cmo_allocs_failed_reset(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct vio_dev *viodev = to_vio_dev(dev); + atomic_set(&viodev->cmo.allocs_failed, 0); + return count; +} + +static ssize_t viodev_cmo_desired_set(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct vio_dev *viodev = to_vio_dev(dev); + size_t new_desired; + int ret; + + ret = strict_strtoul(buf, 10, &new_desired); + if (ret) + return ret; + + vio_cmo_set_dev_desired(viodev, new_desired); + return count; +} + +viodev_cmo_rd_attr(desired); +viodev_cmo_rd_attr(entitled); +viodev_cmo_rd_attr(allocated); + +static ssize_t name_show(struct device *, struct device_attribute *, char *); +static ssize_t devspec_show(struct device *, struct device_attribute *, char *); +static struct device_attribute vio_cmo_dev_attrs[] = { + __ATTR_RO(name), + __ATTR_RO(devspec), + __ATTR(cmo_desired, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH, + viodev_cmo_desired_show, viodev_cmo_desired_set), + __ATTR(cmo_entitled, S_IRUGO, viodev_cmo_entitled_show, NULL), + __ATTR(cmo_allocated, S_IRUGO, viodev_cmo_allocated_show, NULL), + __ATTR(cmo_allocs_failed, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH, + viodev_cmo_allocs_failed_show, viodev_cmo_allocs_failed_reset), + __ATTR_NULL +}; + +/* sysfs bus functions and data structures for CMO */ + +#define viobus_cmo_rd_attr(name) \ +static ssize_t \ +viobus_cmo_##name##_show(struct bus_type *bt, char *buf) \ +{ \ + return sprintf(buf, "%lu\n", vio_cmo.name); \ +} + +#define viobus_cmo_pool_rd_attr(name, var) \ +static ssize_t \ +viobus_cmo_##name##_pool_show_##var(struct bus_type *bt, char *buf) \ +{ \ + return sprintf(buf, "%lu\n", vio_cmo.name.var); \ +} + +static ssize_t viobus_cmo_high_reset(struct bus_type *bt, const char *buf, + size_t count) +{ + unsigned long flags; + + spin_lock_irqsave(&vio_cmo.lock, flags); + vio_cmo.high = vio_cmo.curr; + spin_unlock_irqrestore(&vio_cmo.lock, flags); + + return count; +} + +viobus_cmo_rd_attr(entitled); +viobus_cmo_pool_rd_attr(reserve, size); +viobus_cmo_pool_rd_attr(excess, size); +viobus_cmo_pool_rd_attr(excess, free); +viobus_cmo_rd_attr(spare); +viobus_cmo_rd_attr(min); +viobus_cmo_rd_attr(desired); +viobus_cmo_rd_attr(curr); +viobus_cmo_rd_attr(high); + +static struct bus_attribute vio_cmo_bus_attrs[] = { + __ATTR(cmo_entitled, S_IRUGO, viobus_cmo_entitled_show, NULL), + __ATTR(cmo_reserve_size, S_IRUGO, viobus_cmo_reserve_pool_show_size, NULL), + __ATTR(cmo_excess_size, S_IRUGO, viobus_cmo_excess_pool_show_size, NULL), + __ATTR(cmo_excess_free, S_IRUGO, viobus_cmo_excess_pool_show_free, NULL), + __ATTR(cmo_spare, S_IRUGO, viobus_cmo_spare_show, NULL), + __ATTR(cmo_min, S_IRUGO, viobus_cmo_min_show, NULL), + __ATTR(cmo_desired, S_IRUGO, viobus_cmo_desired_show, NULL), + __ATTR(cmo_curr, S_IRUGO, viobus_cmo_curr_show, NULL), + __ATTR(cmo_high, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH, + viobus_cmo_high_show, viobus_cmo_high_reset), + __ATTR_NULL +}; + +static void vio_cmo_sysfs_init(void) +{ + vio_bus_type.dev_attrs = vio_cmo_dev_attrs; + vio_bus_type.bus_attrs = vio_cmo_bus_attrs; +} +#else /* CONFIG_PPC_SMLPAR */ +/* Dummy functions for iSeries platform */ +int vio_cmo_entitlement_update(size_t new_entitlement) { return 0; } +void vio_cmo_set_dev_desired(struct vio_dev *viodev, size_t desired) {} +static int vio_cmo_bus_probe(struct vio_dev *viodev) { return 0; } +static void vio_cmo_bus_remove(struct vio_dev *viodev) {} +static void vio_cmo_set_dma_ops(struct vio_dev *viodev) {} +static void vio_cmo_bus_init(void) {} +static void vio_cmo_sysfs_init(void) { } +#endif /* CONFIG_PPC_SMLPAR */ +EXPORT_SYMBOL(vio_cmo_entitlement_update); +EXPORT_SYMBOL(vio_cmo_set_dev_desired); + static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev) { const unsigned char *dma_window; @@ -114,8 +1105,17 @@ static int vio_bus_probe(struct device *dev) return error; id = vio_match_device(viodrv->id_table, viodev); - if (id) + if (id) { + memset(&viodev->cmo, 0, sizeof(viodev->cmo)); + if (firmware_has_feature(FW_FEATURE_CMO)) { + error = vio_cmo_bus_probe(viodev); + if (error) + return error; + } error = viodrv->probe(viodev, id); + if (error) + vio_cmo_bus_remove(viodev); + } return error; } @@ -125,12 +1125,23 @@ static int vio_bus_remove(struct device *dev) { struct vio_dev *viodev = to_vio_dev(dev); struct vio_driver *viodrv = to_vio_driver(dev->driver); + struct device *devptr; + int ret = 1; + + /* + * Hold a reference to the device after the remove function is called + * to allow for CMO accounting cleanup for the device. + */ + devptr = get_device(dev); if (viodrv->remove) - return viodrv->remove(viodev); + ret = viodrv->remove(viodev); + + if (!ret && firmware_has_feature(FW_FEATURE_CMO)) + vio_cmo_bus_remove(viodev); - /* driver can't remove */ - return 1; + put_device(devptr); + return ret; } /** @@ -215,7 +1226,11 @@ struct vio_dev *vio_register_device_node(struct device_node *of_node) viodev->unit_address = *unit_address; } viodev->dev.archdata.of_node = of_node_get(of_node); - viodev->dev.archdata.dma_ops = &dma_iommu_ops; + + if (firmware_has_feature(FW_FEATURE_CMO)) + vio_cmo_set_dma_ops(viodev); + else + viodev->dev.archdata.dma_ops = &dma_iommu_ops; viodev->dev.archdata.dma_data = vio_build_iommu_table(viodev); viodev->dev.archdata.numa_node = of_node_to_nid(of_node); @@ -245,6 +1260,9 @@ static int __init vio_bus_init(void) int err; struct device_node *node_vroot; + if (firmware_has_feature(FW_FEATURE_CMO)) + vio_cmo_sysfs_init(); + err = bus_register(&vio_bus_type); if (err) { printk(KERN_ERR "failed to register VIO bus\n"); @@ -262,6 +1280,9 @@ static int __init vio_bus_init(void) return err; } + if (firmware_has_feature(FW_FEATURE_CMO)) + vio_cmo_bus_init(); + node_vroot = of_find_node_by_name(NULL, "vdevice"); if (node_vroot) { struct device_node *of_node; |