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#include "vm/mmap.h"
#include "errno.h"
#include "fs/file.h"
#include "fs/vfs.h"
#include "fs/vnode.h"
#include "globals.h"
#include "mm/mm.h"
#include "mm/mman.h"
#include "mm/tlb.h"
#include "util/debug.h"
/*
* This function implements the mmap(2) syscall: Add a mapping to the current
* process's address space. Supports the following flags: MAP_SHARED,
* MAP_PRIVATE, MAP_FIXED, and MAP_ANON.
*
* ret - If provided, on success, *ret must point to the start of the mapped area
*
* Return 0 on success, or:
* - EACCES:
* - a file mapping was requested, but fd is not open for reading.
* - MAP_SHARED was requested and PROT_WRITE is set, but fd is
* not open in read/write (O_RDWR) mode.
* - PROT_WRITE is set, but the file has FMODE_APPEND specified.
* - EBADF:
* - fd is not a valid file descriptor and MAP_ANON was
* not set
* - EINVAL:
* - addr is not page aligned and MAP_FIXED is specified
* - addr is out of range of the user address space and MAP_FIXED is specified
* - off is not page aligned
* - len is <= 0 or off < 0
* - flags do not contain MAP_PRIVATE or MAP_SHARED
* - ENODEV:
* - The underlying filesystem of the specified file does not
* support memory mapping or in other words, the file's vnode's mmap
* operation doesn't exist
* - Propagate errors from vmmap_map()
*
* See the errors section of the mmap(2) man page for more details
*
* Hints:
* 1) A lot of error checking.
* 2) Call vmmap_map() to create the mapping.
* a) Use VMMAP_DIR_HILO as default, which will make other stencil code in
* Weenix happy.
* 3) Call tlb_flush_range() on the newly-mapped region. This is because the
* newly-mapped region could have been used by someone else, and you don't
* want to get stale mappings.
* 4) Don't forget to set ret if it was provided.
*
* If you are mapping less than a page, make sure that you are still allocating
* a full page.
*/
long do_mmap(void *addr, size_t len, int prot, int flags, int fd, off_t off,
void **ret)
{
NOT_YET_IMPLEMENTED("VM: do_mmap");
return -1;
}
/*
* This function implements the munmap(2) syscall.
*
* Return 0 on success, or:
* - EINVAL:
* - addr is not aligned on a page boundary
* - the region to unmap is out of range of the user address space
* - len is 0
* - Propagate errors from vmmap_remove()
*
* See the errors section of the munmap(2) man page for more details
*
* Hints:
* - Similar to do_mmap():
* 1) Perform error checking.
* 2) Call vmmap_remove().
*/
long do_munmap(void *addr, size_t len)
{
NOT_YET_IMPLEMENTED("VM: do_munmap");
return -1;
}
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