diff options
Diffstat (limited to 'REORG.TODO/sysdeps/mach/hurd/mmap.c')
| -rw-r--r-- | REORG.TODO/sysdeps/mach/hurd/mmap.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/mach/hurd/mmap.c b/REORG.TODO/sysdeps/mach/hurd/mmap.c new file mode 100644 index 0000000000..dbd718a688 --- /dev/null +++ b/REORG.TODO/sysdeps/mach/hurd/mmap.c @@ -0,0 +1,188 @@ +/* Copyright (C) 1994-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <sys/types.h> +#include <sys/mman.h> +#include <errno.h> +#include <hurd.h> +#include <hurd/fd.h> + +/* Map addresses starting near ADDR and extending for LEN bytes. from + OFFSET into the file FD describes according to PROT and FLAGS. If ADDR + is nonzero, it is the desired mapping address. If the MAP_FIXED bit is + set in FLAGS, the mapping will be at ADDR exactly (which must be + page-aligned); otherwise the system chooses a convenient nearby address. + The return value is the actual mapping address chosen or (__ptr_t) -1 + for errors (in which case `errno' is set). A successful `mmap' call + deallocates any previous mapping for the affected region. */ + +__ptr_t +__mmap (__ptr_t addr, size_t len, int prot, int flags, int fd, off_t offset) +{ + error_t err; + vm_prot_t vmprot; + memory_object_t memobj; + vm_address_t mapaddr; + + mapaddr = (vm_address_t) addr; + + /* ADDR and OFFSET must be page-aligned. */ + if ((mapaddr & (__vm_page_size - 1)) || (offset & (__vm_page_size - 1))) + return (__ptr_t) (long int) __hurd_fail (EINVAL); + + if ((flags & (MAP_TYPE|MAP_INHERIT)) == MAP_ANON + && prot == (PROT_READ|PROT_WRITE)) /* cf VM_PROT_DEFAULT */ + { + /* vm_allocate has (a little) less overhead in the kernel too. */ + err = __vm_allocate (__mach_task_self (), &mapaddr, len, mapaddr == 0); + + if (err == KERN_NO_SPACE) + { + if (flags & MAP_FIXED) + { + /* XXX this is not atomic as it is in unix! */ + /* The region is already allocated; deallocate it first. */ + err = __vm_deallocate (__mach_task_self (), mapaddr, len); + if (!err) + err = __vm_allocate (__mach_task_self (), &mapaddr, len, 0); + } + else if (mapaddr != 0) + err = __vm_allocate (__mach_task_self (), &mapaddr, len, 1); + } + + return err ? (__ptr_t) (long int) __hurd_fail (err) : (__ptr_t) mapaddr; + } + + vmprot = VM_PROT_NONE; + if (prot & PROT_READ) + vmprot |= VM_PROT_READ; + if (prot & PROT_WRITE) + vmprot |= VM_PROT_WRITE; + if (prot & PROT_EXEC) + vmprot |= VM_PROT_EXECUTE; + + switch (flags & MAP_TYPE) + { + default: + return (__ptr_t) (long int) __hurd_fail (EINVAL); + + case MAP_ANON: + memobj = MACH_PORT_NULL; + break; + + case MAP_FILE: + case 0: /* Allow, e.g., just MAP_SHARED. */ + { + mach_port_t robj, wobj; + if (err = HURD_DPORT_USE (fd, __io_map (port, &robj, &wobj))) + { + if (err == MIG_BAD_ID || err == EOPNOTSUPP || err == ENOSYS) + err = ENODEV; /* File descriptor doesn't support mmap. */ + return (__ptr_t) (long int) __hurd_dfail (fd, err); + } + switch (prot & (PROT_READ|PROT_WRITE)) + { + /* Although it apparently doesn't make sense to map a file with + protection set to PROT_NONE, it is actually sometimes done. + In particular, that's how localedef reserves some space for + the locale archive file, the rationale being that some + implementations take into account whether the mapping is + anonymous or not when selecting addresses. */ + case PROT_NONE: + case PROT_READ: + memobj = robj; + if (wobj != MACH_PORT_NULL) + __mach_port_deallocate (__mach_task_self (), wobj); + break; + case PROT_WRITE: + memobj = wobj; + if (robj != MACH_PORT_NULL) + __mach_port_deallocate (__mach_task_self (), robj); + break; + case PROT_READ|PROT_WRITE: + if (robj == wobj) + { + memobj = wobj; + /* Remove extra reference. */ + __mach_port_deallocate (__mach_task_self (), memobj); + } + else if (wobj == MACH_PORT_NULL && /* Not writable by mapping. */ + !(flags & MAP_SHARED)) + /* The file can only be mapped for reading. Since we are + making a private mapping, we will never try to write the + object anyway, so we don't care. */ + memobj = robj; + else + { + __mach_port_deallocate (__mach_task_self (), wobj); + return (__ptr_t) (long int) __hurd_fail (EACCES); + } + break; + default: + __builtin_unreachable (); + } + break; + /* XXX handle MAP_NOEXTEND */ + } + } + + /* XXX handle MAP_INHERIT */ + + err = __vm_map (__mach_task_self (), + &mapaddr, (vm_size_t) len, (vm_address_t) 0, + mapaddr == 0, + memobj, (vm_offset_t) offset, + ! (flags & MAP_SHARED), + vmprot, VM_PROT_ALL, + (flags & MAP_SHARED) ? VM_INHERIT_SHARE : VM_INHERIT_COPY); + + if (err == KERN_NO_SPACE) + { + if (flags & MAP_FIXED) + { + /* XXX this is not atomic as it is in unix! */ + /* The region is already allocated; deallocate it first. */ + err = __vm_deallocate (__mach_task_self (), mapaddr, len); + if (! err) + err = __vm_map (__mach_task_self (), + &mapaddr, (vm_size_t) len, (vm_address_t) 0, + 0, memobj, (vm_offset_t) offset, + ! (flags & MAP_SHARED), + vmprot, VM_PROT_ALL, + (flags & MAP_SHARED) ? VM_INHERIT_SHARE + : VM_INHERIT_COPY); + } + else if (mapaddr != 0) + err = __vm_map (__mach_task_self (), + &mapaddr, (vm_size_t) len, (vm_address_t) 0, + 1, memobj, (vm_offset_t) offset, + ! (flags & MAP_SHARED), + vmprot, VM_PROT_ALL, + (flags & MAP_SHARED) ? VM_INHERIT_SHARE + : VM_INHERIT_COPY); + } + + if (memobj != MACH_PORT_NULL) + __mach_port_deallocate (__mach_task_self (), memobj); + + if (err) + return (__ptr_t) (long int) __hurd_fail (err); + + return (__ptr_t) mapaddr; +} + +weak_alias (__mmap, mmap) |