diff options
Diffstat (limited to 'drivers/infiniband/sw/rdmavt/mmap.c')
| -rw-r--r-- | drivers/infiniband/sw/rdmavt/mmap.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/drivers/infiniband/sw/rdmavt/mmap.c b/drivers/infiniband/sw/rdmavt/mmap.c new file mode 100644 index 000000000..4d2238f3f --- /dev/null +++ b/drivers/infiniband/sw/rdmavt/mmap.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause +/* + * Copyright(c) 2016 Intel Corporation. + */ + +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <rdma/uverbs_ioctl.h> +#include "mmap.h" + +/** + * rvt_mmap_init - init link list and lock for mem map + * @rdi: rvt dev struct + */ +void rvt_mmap_init(struct rvt_dev_info *rdi) +{ + INIT_LIST_HEAD(&rdi->pending_mmaps); + spin_lock_init(&rdi->pending_lock); + rdi->mmap_offset = PAGE_SIZE; + spin_lock_init(&rdi->mmap_offset_lock); +} + +/** + * rvt_release_mmap_info - free mmap info structure + * @ref: a pointer to the kref within struct rvt_mmap_info + */ +void rvt_release_mmap_info(struct kref *ref) +{ + struct rvt_mmap_info *ip = + container_of(ref, struct rvt_mmap_info, ref); + struct rvt_dev_info *rdi = ib_to_rvt(ip->context->device); + + spin_lock_irq(&rdi->pending_lock); + list_del(&ip->pending_mmaps); + spin_unlock_irq(&rdi->pending_lock); + + vfree(ip->obj); + kfree(ip); +} + +static void rvt_vma_open(struct vm_area_struct *vma) +{ + struct rvt_mmap_info *ip = vma->vm_private_data; + + kref_get(&ip->ref); +} + +static void rvt_vma_close(struct vm_area_struct *vma) +{ + struct rvt_mmap_info *ip = vma->vm_private_data; + + kref_put(&ip->ref, rvt_release_mmap_info); +} + +static const struct vm_operations_struct rvt_vm_ops = { + .open = rvt_vma_open, + .close = rvt_vma_close, +}; + +/** + * rvt_mmap - create a new mmap region + * @context: the IB user context of the process making the mmap() call + * @vma: the VMA to be initialized + * + * Return: zero if the mmap is OK. Otherwise, return an errno. + */ +int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) +{ + struct rvt_dev_info *rdi = ib_to_rvt(context->device); + unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; + unsigned long size = vma->vm_end - vma->vm_start; + struct rvt_mmap_info *ip, *pp; + int ret = -EINVAL; + + /* + * Search the device's list of objects waiting for a mmap call. + * Normally, this list is very short since a call to create a + * CQ, QP, or SRQ is soon followed by a call to mmap(). + */ + spin_lock_irq(&rdi->pending_lock); + list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps, + pending_mmaps) { + /* Only the creator is allowed to mmap the object */ + if (context != ip->context || (__u64)offset != ip->offset) + continue; + /* Don't allow a mmap larger than the object. */ + if (size > ip->size) + break; + + list_del_init(&ip->pending_mmaps); + spin_unlock_irq(&rdi->pending_lock); + + ret = remap_vmalloc_range(vma, ip->obj, 0); + if (ret) + goto done; + vma->vm_ops = &rvt_vm_ops; + vma->vm_private_data = ip; + rvt_vma_open(vma); + goto done; + } + spin_unlock_irq(&rdi->pending_lock); +done: + return ret; +} + +/** + * rvt_create_mmap_info - allocate information for hfi1_mmap + * @rdi: rvt dev struct + * @size: size in bytes to map + * @udata: user data (must be valid!) + * @obj: opaque pointer to a cq, wq etc + * + * Return: rvt_mmap struct on success, ERR_PTR on failure + */ +struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size, + struct ib_udata *udata, void *obj) +{ + struct rvt_mmap_info *ip; + + if (!udata) + return ERR_PTR(-EINVAL); + + ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node); + if (!ip) + return ERR_PTR(-ENOMEM); + + size = PAGE_ALIGN(size); + + spin_lock_irq(&rdi->mmap_offset_lock); + if (rdi->mmap_offset == 0) + rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA); + ip->offset = rdi->mmap_offset; + rdi->mmap_offset += ALIGN(size, SHMLBA); + spin_unlock_irq(&rdi->mmap_offset_lock); + + INIT_LIST_HEAD(&ip->pending_mmaps); + ip->size = size; + ip->context = + container_of(udata, struct uverbs_attr_bundle, driver_udata) + ->context; + ip->obj = obj; + kref_init(&ip->ref); + + return ip; +} + +/** + * rvt_update_mmap_info - update a mem map + * @rdi: rvt dev struct + * @ip: mmap info pointer + * @size: size to grow by + * @obj: opaque pointer to cq, wq, etc. + */ +void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip, + u32 size, void *obj) +{ + size = PAGE_ALIGN(size); + + spin_lock_irq(&rdi->mmap_offset_lock); + if (rdi->mmap_offset == 0) + rdi->mmap_offset = PAGE_SIZE; + ip->offset = rdi->mmap_offset; + rdi->mmap_offset += size; + spin_unlock_irq(&rdi->mmap_offset_lock); + + ip->size = size; + ip->obj = obj; +} |