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| author | Hans Petter Selasky <hselasky@FreeBSD.org> | 2021-05-11 18:49:13 +0000 |
|---|---|---|
| committer | Hans Petter Selasky <hselasky@FreeBSD.org> | 2021-06-02 11:25:20 +0000 |
| commit | 28d95cc69fee30b160418d83bebaf7fddae6058e (patch) | |
| tree | fdc057d12984da9ec7aa30f0ef9c5a741da342ae | |
| parent | fba2292d65e04d3a07eb5d089f511f230d344ac8 (diff) | |
| download | src-28d95cc69fee30b160418d83bebaf7fddae6058e.tar.gz src-28d95cc69fee30b160418d83bebaf7fddae6058e.zip | |
Implement read-only VM_SHARED flag in the LinuxKPI.
For use by mmap(2) callbacks.
Sponsored by: Mellanox Technologies // NVIDIA Networking
(cherry picked from commit 904390b4787d2e4a0d9d8ca9cb0d6da5a4fb320c)
| -rw-r--r-- | sys/compat/linuxkpi/common/include/linux/mm.h | 1 | ||||
| -rw-r--r-- | sys/compat/linuxkpi/common/src/linux_compat.c | 14 |
2 files changed, 9 insertions, 6 deletions
diff --git a/sys/compat/linuxkpi/common/include/linux/mm.h b/sys/compat/linuxkpi/common/include/linux/mm.h index f6f53afbc8a9..68a0f34acaf3 100644 --- a/sys/compat/linuxkpi/common/include/linux/mm.h +++ b/sys/compat/linuxkpi/common/include/linux/mm.h @@ -63,6 +63,7 @@ CTASSERT((VM_PROT_ALL & -(1 << 8)) == 0); #define VM_DONTCOPY (1 << 14) #define VM_DONTEXPAND (1 << 15) #define VM_DONTDUMP (1 << 16) +#define VM_SHARED (1 << 17) #define VMA_MAX_PREFAULT_RECORD 1 diff --git a/sys/compat/linuxkpi/common/src/linux_compat.c b/sys/compat/linuxkpi/common/src/linux_compat.c index 0fc0ad702788..4337f1f7bbd7 100644 --- a/sys/compat/linuxkpi/common/src/linux_compat.c +++ b/sys/compat/linuxkpi/common/src/linux_compat.c @@ -1226,7 +1226,7 @@ linux_file_kqfilter(struct file *file, struct knote *kn) static int linux_file_mmap_single(struct file *fp, const struct file_operations *fop, vm_ooffset_t *offset, vm_size_t size, struct vm_object **object, - int nprot, struct thread *td) + int nprot, bool is_shared, struct thread *td) { struct task_struct *task; struct vm_area_struct *vmap; @@ -1261,6 +1261,8 @@ linux_file_mmap_single(struct file *fp, const struct file_operations *fop, vmap->vm_pgoff = *offset / PAGE_SIZE; vmap->vm_pfn = 0; vmap->vm_flags = vmap->vm_page_prot = (nprot & VM_PROT_ALL); + if (is_shared) + vmap->vm_flags |= VM_SHARED; vmap->vm_ops = NULL; vmap->vm_file = get_file(filp); vmap->vm_mm = mm; @@ -1595,21 +1597,21 @@ linux_file_ioctl(struct file *fp, u_long cmd, void *data, struct ucred *cred, static int linux_file_mmap_sub(struct thread *td, vm_size_t objsize, vm_prot_t prot, - vm_prot_t *maxprotp, int *flagsp, struct file *fp, + vm_prot_t maxprot, int flags, struct file *fp, vm_ooffset_t *foff, const struct file_operations *fop, vm_object_t *objp) { /* * Character devices do not provide private mappings * of any kind: */ - if ((*maxprotp & VM_PROT_WRITE) == 0 && + if ((maxprot & VM_PROT_WRITE) == 0 && (prot & VM_PROT_WRITE) != 0) return (EACCES); - if ((*flagsp & (MAP_PRIVATE | MAP_COPY)) != 0) + if ((flags & (MAP_PRIVATE | MAP_COPY)) != 0) return (EINVAL); return (linux_file_mmap_single(fp, fop, foff, objsize, objp, - (int)prot, td)); + (int)prot, (flags & MAP_SHARED) ? true : false, td)); } static int @@ -1667,7 +1669,7 @@ linux_file_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size maxprot &= cap_maxprot; linux_get_fop(filp, &fop, &ldev); - error = linux_file_mmap_sub(td, size, prot, &maxprot, &flags, fp, + error = linux_file_mmap_sub(td, size, prot, maxprot, flags, fp, &foff, fop, &object); if (error != 0) goto out; |