From 61b7ea7a3d584e252d6a42319c9720a2e990e819 Mon Sep 17 00:00:00 2001 From: jhb Date: Thu, 3 Sep 2015 18:27:39 +0000 Subject: Currently the Linux character device mmap handling only supports mmap operations that map a single page that has an associated vm_page_t. This does not permit mapping larger regions (such as a PCI memory BAR) and it does not permit mapping addresses beyond the top of RAM (such as a 64-bit BAR located above the top of RAM). Instead of using a single OBJT_DEVICE object and passing the physaddr via the offset as a hack, create a new sglist and OBJT_SG object for each mmap request. The requested memory attribute is applied to the object thus affecting all pages mapped by the request. Reviewed by: hselasky, np MFC after: 1 week Sponsored by: Chelsio Differential Revision: https://reviews.freebsd.org/D3386 --- sys/ofed/include/linux/linux_compat.c | 45 ++++++++++++++++------------------- sys/ofed/include/linux/mm.h | 2 ++ 2 files changed, 22 insertions(+), 25 deletions(-) (limited to 'sys') diff --git a/sys/ofed/include/linux/linux_compat.c b/sys/ofed/include/linux/linux_compat.c index 1acf08e..d082eeb 100644 --- a/sys/ofed/include/linux/linux_compat.c +++ b/sys/ofed/include/linux/linux_compat.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -416,16 +417,6 @@ linux_dev_poll(struct cdev *dev, int events, struct thread *td) } static int -linux_dev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, - int nprot, vm_memattr_t *memattr) -{ - - /* XXX memattr not honored. */ - *paddr = offset; - return (0); -} - -static int linux_dev_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size, struct vm_object **object, int nprot) { @@ -433,36 +424,41 @@ linux_dev_mmap_single(struct cdev *dev, vm_ooffset_t *offset, struct linux_file *filp; struct file *file; struct vm_area_struct vma; - vm_paddr_t paddr; - vm_page_t m; int error; file = curthread->td_fpop; ldev = dev->si_drv1; if (ldev == NULL) return (ENODEV); - if (size != PAGE_SIZE) - return (EINVAL); if ((error = devfs_get_cdevpriv((void **)&filp)) != 0) return (error); filp->f_flags = file->f_flag; vma.vm_start = 0; - vma.vm_end = PAGE_SIZE; + vma.vm_end = size; vma.vm_pgoff = *offset / PAGE_SIZE; vma.vm_pfn = 0; vma.vm_page_prot = 0; if (filp->f_op->mmap) { error = -filp->f_op->mmap(filp, &vma); if (error == 0) { - paddr = (vm_paddr_t)vma.vm_pfn << PAGE_SHIFT; - *offset = paddr; - m = PHYS_TO_VM_PAGE(paddr); - *object = vm_pager_allocate(OBJT_DEVICE, dev, - PAGE_SIZE, nprot, *offset, curthread->td_ucred); - if (*object == NULL) - return (EINVAL); - if (vma.vm_page_prot != VM_MEMATTR_DEFAULT) - pmap_page_set_memattr(m, vma.vm_page_prot); + struct sglist *sg; + + sg = sglist_alloc(1, M_WAITOK); + sglist_append_phys(sg, + (vm_paddr_t)vma.vm_pfn << PAGE_SHIFT, vma.vm_len); + *object = vm_pager_allocate(OBJT_SG, sg, vma.vm_len, + nprot, 0, curthread->td_ucred); + if (*object == NULL) { + sglist_free(sg); + return (EINVAL); + } + *offset = 0; + if (vma.vm_page_prot != VM_MEMATTR_DEFAULT) { + VM_OBJECT_WLOCK(*object); + vm_object_set_memattr(*object, + vma.vm_page_prot); + VM_OBJECT_WUNLOCK(*object); + } } } else error = ENODEV; @@ -479,7 +475,6 @@ struct cdevsw linuxcdevsw = { .d_write = linux_dev_write, .d_ioctl = linux_dev_ioctl, .d_mmap_single = linux_dev_mmap_single, - .d_mmap = linux_dev_mmap, .d_poll = linux_dev_poll, }; diff --git a/sys/ofed/include/linux/mm.h b/sys/ofed/include/linux/mm.h index 80d59e8..b1a575c 100644 --- a/sys/ofed/include/linux/mm.h +++ b/sys/ofed/include/linux/mm.h @@ -40,6 +40,7 @@ struct vm_area_struct { vm_offset_t vm_end; vm_offset_t vm_pgoff; vm_paddr_t vm_pfn; /* PFN For mmap. */ + vm_size_t vm_len; /* length for mmap. */ vm_memattr_t vm_page_prot; }; @@ -78,6 +79,7 @@ io_remap_pfn_range(struct vm_area_struct *vma, { vma->vm_page_prot = prot; vma->vm_pfn = pfn; + vma->vm_len = size; return (0); } -- cgit v1.1