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Diffstat (limited to 'winsup/cygwin/mmap.cc')
| -rw-r--r-- | winsup/cygwin/mmap.cc | 1835 |
1 files changed, 0 insertions, 1835 deletions
diff --git a/winsup/cygwin/mmap.cc b/winsup/cygwin/mmap.cc deleted file mode 100644 index 57e0a40e7..000000000 --- a/winsup/cygwin/mmap.cc +++ /dev/null @@ -1,1835 +0,0 @@ -/* mmap.cc - - Copyright 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2004, 2005, - 2006, 2007, 2008, 2009, 2010 Red Hat, Inc. - -This file is part of Cygwin. - -This software is a copyrighted work licensed under the terms of the -Cygwin license. Please consult the file "CYGWIN_LICENSE" for -details. */ - -#include "winsup.h" -#include "miscfuncs.h" -#include <unistd.h> -#include <stdlib.h> -#include <sys/mman.h> -#include <sys/param.h> -#include "cygerrno.h" -#include "security.h" -#include "path.h" -#include "fhandler.h" -#include "dtable.h" -#include "cygheap.h" -#include "ntdll.h" -#include <sys/queue.h> - -/* __PROT_ATTACH indicates an anonymous mapping which is supposed to be - attached to a file mapping for pages beyond the file's EOF. The idea - is to support mappings longer than the file, without the file growing - to mapping length (POSIX semantics). */ -#define __PROT_ATTACH 0x8000000 -/* Filler pages are the pages from the last file backed page to the next - 64K boundary. These pages are created as anonymous pages, but with - the same page protection as the file's pages, since POSIX applications - expect to be able to access this part the same way as the file pages. */ -#define __PROT_FILLER 0x4000000 - -/* Stick with 4K pages for bookkeeping, otherwise we just get confused - when trying to do file mappings with trailing filler pages correctly. */ -#define PAGE_CNT(bytes) howmany((bytes),getsystempagesize()) - -#define PGBITS (sizeof (DWORD)*8) -#define MAPSIZE(pages) howmany ((pages), PGBITS) - -#define MAP_SET(n) (page_map[(n)/PGBITS] |= (1L << ((n) % PGBITS))) -#define MAP_CLR(n) (page_map[(n)/PGBITS] &= ~(1L << ((n) % PGBITS))) -#define MAP_ISSET(n) (page_map[(n)/PGBITS] & (1L << ((n) % PGBITS))) - -/* Used for anonymous mappings. */ -static fhandler_dev_zero fh_anonymous; - -/* Used for thread synchronization while accessing mmap bookkeeping lists. */ -static NO_COPY muto mmap_guard; -#define LIST_LOCK() (mmap_guard.init ("mmap_guard")->acquire ()) -#define LIST_UNLOCK() (mmap_guard.release ()) - -/* Small helpers to avoid having lots of flag bit tests in the code. */ -static inline bool -priv (int flags) -{ - return (flags & MAP_PRIVATE) == MAP_PRIVATE; -} - -static inline bool -fixed (int flags) -{ - return (flags & MAP_FIXED) == MAP_FIXED; -} - -static inline bool -anonymous (int flags) -{ - return (flags & MAP_ANONYMOUS) == MAP_ANONYMOUS; -} - -static inline bool -noreserve (int flags) -{ - return (flags & MAP_NORESERVE) == MAP_NORESERVE; -} - -static inline bool -autogrow (int flags) -{ - return (flags & MAP_AUTOGROW) == MAP_AUTOGROW; -} - -static inline bool -attached (int prot) -{ - return (prot & __PROT_ATTACH) == __PROT_ATTACH; -} - -static inline bool -filler (int prot) -{ - return (prot & __PROT_FILLER) == __PROT_FILLER; -} - -static inline DWORD -gen_create_protect (DWORD openflags, int flags) -{ - DWORD ret = PAGE_READONLY; - - if (priv (flags)) - ret = PAGE_WRITECOPY; - else if (openflags & GENERIC_WRITE) - ret = PAGE_READWRITE; - - if (openflags & GENERIC_EXECUTE) - ret <<= 4; - - return ret; -} - -/* Generate Windows protection flags from mmap prot and flag values. */ -static inline DWORD -gen_protect (int prot, int flags) -{ - DWORD ret = PAGE_NOACCESS; - - /* Attached pages are only reserved, but the protection must be a - valid value, so we just return PAGE_READWRITE. */ - if (attached (prot)) - return PAGE_EXECUTE_READWRITE; - - if (prot & PROT_WRITE) - ret = (priv (flags) && (!anonymous (flags) || filler (prot))) - ? PAGE_WRITECOPY : PAGE_READWRITE; - else if (prot & PROT_READ) - ret = PAGE_READONLY; - - if (prot & PROT_EXEC) - ret <<= 4; - - return ret; -} - -static HANDLE -CreateMapping (HANDLE fhdl, size_t len, _off64_t off, DWORD openflags, - int prot, int flags) -{ - HANDLE h; - NTSTATUS ret; - - LARGE_INTEGER sectionsize = { QuadPart: len }; - ULONG protect = gen_create_protect (openflags, flags); - ULONG attributes = attached (prot) ? SEC_RESERVE : SEC_COMMIT; - - OBJECT_ATTRIBUTES oa; - InitializeObjectAttributes (&oa, NULL, OBJ_INHERIT, NULL, - sec_none.lpSecurityDescriptor); - - if (fhdl == INVALID_HANDLE_VALUE) - { - /* Standard anonymous mapping needs non-zero len. */ - ret = NtCreateSection (&h, SECTION_ALL_ACCESS, &oa, - §ionsize, protect, attributes, NULL); - } - else if (autogrow (flags)) - { - /* Auto-grow only works if the protection is PAGE_READWRITE. So, - first we call NtCreateSection with PAGE_READWRITE, then, if the - requested protection is different, we close the mapping and - reopen it again with the correct protection, if auto-grow worked. */ - sectionsize.QuadPart += off; - ret = NtCreateSection (&h, SECTION_ALL_ACCESS, &oa, - §ionsize, PAGE_READWRITE, attributes, fhdl); - if (NT_SUCCESS (ret) && protect != PAGE_READWRITE) - { - NtClose (h); - ret = NtCreateSection (&h, SECTION_ALL_ACCESS, &oa, - §ionsize, protect, attributes, fhdl); - } - } - else - { - /* Zero len creates mapping for whole file and allows - AT_EXTENDABLE_FILE mapping, if we ever use it... */ - sectionsize.QuadPart = 0; - ret = NtCreateSection (&h, SECTION_ALL_ACCESS, &oa, - §ionsize, protect, attributes, fhdl); - } - if (!NT_SUCCESS (ret)) - { - h = NULL; - SetLastError (RtlNtStatusToDosError (ret)); - } - return h; -} - -static void * -MapView (HANDLE h, void *addr, size_t len, DWORD openflags, - int prot, int flags, _off64_t off) -{ - NTSTATUS ret; - LARGE_INTEGER offset = { QuadPart:off }; - DWORD protect = gen_create_protect (openflags, flags); - void *base = addr; - ULONG commitsize = attached (prot) ? 0 : len; - ULONG viewsize = len; - ULONG alloc_type = (base && !wincap.is_wow64 () ? AT_ROUND_TO_PAGE : 0) - | MEM_TOP_DOWN; - - /* Try mapping using the given address first, even if it's NULL. - If it failed, and addr was not NULL and flags is not MAP_FIXED, - try again with NULL address. - - Note: Retrying the mapping might be unnecessary, now that mmap64 checks - for a valid memory area first. */ - ret = NtMapViewOfSection (h, NtCurrentProcess (), &base, 0, commitsize, - &offset, &viewsize, ViewShare, alloc_type, protect); - if (!NT_SUCCESS (ret) && addr && !fixed (flags)) - { - base = NULL; - ret = NtMapViewOfSection (h, NtCurrentProcess (), &base, 0, commitsize, - &offset, &viewsize, ViewShare, 0, protect); - } - if (!NT_SUCCESS (ret)) - { - base = NULL; - SetLastError (RtlNtStatusToDosError (ret)); - } - debug_printf ("%p (status %p) = NtMapViewOfSection (h:%x, addr:%x, len:%u," - " off:%X, protect:%x, type:%x)", - base, ret, h, addr, len, off, protect, 0); - return base; -} - -/* Class structure used to keep a record of all current mmap areas - in a process. Needed for bookkeeping all mmaps in a process and - for duplicating all mmaps after fork() since mmaps are not propagated - to child processes by Windows. All information must be duplicated - by hand, see fixup_mmaps_after_fork(). - - The class structure: - - One member of class map per process, global variable mmapped_areas. - Contains a singly-linked list of type class mmap_list. Each mmap_list - entry represents all mapping to a file, keyed by file descriptor and - file name hash. - Each list entry contains a singly-linked list of type class mmap_record. - Each mmap_record represents exactly one mapping. For each mapping, there's - an additional so called `page_map'. It's an array of bits, one bit - per mapped memory page. The bit is set if the page is accessible, - unset otherwise. */ - -class mmap_record -{ - public: - LIST_ENTRY (mmap_record) mr_next; - - private: - int fd; - HANDLE mapping_hdl; - DWORD openflags; - int prot; - int flags; - _off64_t offset; - DWORD len; - caddr_t base_address; - DWORD *page_map; - device dev; - - public: - mmap_record (int nfd, HANDLE h, DWORD of, int p, int f, _off64_t o, DWORD l, - caddr_t b) : - fd (nfd), - mapping_hdl (h), - openflags (of), - prot (p), - flags (f), - offset (o), - len (l), - base_address (b), - page_map (NULL) - { - dev.devn = 0; - if (fd >= 0 && !cygheap->fdtab.not_open (fd)) - dev = cygheap->fdtab[fd]->dev (); - else if (fd == -1) - dev.parse (FH_ZERO); - } - - int get_fd () const { return fd; } - HANDLE get_handle () const { return mapping_hdl; } - device& get_device () { return dev; } - int get_prot () const { return prot; } - int get_openflags () const { return openflags; } - int get_flags () const { return flags; } - bool priv () const { return ::priv (flags); } - bool fixed () const { return ::fixed (flags); } - bool anonymous () const { return ::anonymous (flags); } - bool noreserve () const { return ::noreserve (flags); } - bool autogrow () const { return ::autogrow (flags); } - bool attached () const { return ::attached (prot); } - bool filler () const { return ::filler (prot); } - _off64_t get_offset () const { return offset; } - DWORD get_len () const { return len; } - caddr_t get_address () const { return base_address; } - - bool alloc_page_map (); - void free_page_map () { if (page_map) cfree (page_map); } - - DWORD find_unused_pages (DWORD pages) const; - bool match (caddr_t addr, DWORD len, caddr_t &m_addr, DWORD &m_len); - _off64_t map_pages (_off64_t off, DWORD len); - bool map_pages (caddr_t addr, DWORD len); - bool unmap_pages (caddr_t addr, DWORD len); - int access (caddr_t address); - - fhandler_base *alloc_fh (); - void free_fh (fhandler_base *fh); - - DWORD gen_create_protect () const - { return ::gen_create_protect (get_openflags (), get_flags ()); } - DWORD gen_protect () const - { return ::gen_protect (get_prot (), get_flags ()); } - bool compatible_flags (int fl) const; -}; - -class mmap_list -{ - public: - LIST_ENTRY (mmap_list) ml_next; - LIST_HEAD (, mmap_record) recs; - - private: - int fd; - __ino64_t hash; - - public: - int get_fd () const { return fd; } - __ino64_t get_hash () const { return hash; } - - bool anonymous () const { return fd == -1; } - void set (int nfd, struct __stat64 *st); - mmap_record *add_record (mmap_record r); - bool del_record (mmap_record *rec); - caddr_t try_map (void *addr, size_t len, int flags, _off64_t off); -}; - -class mmap_areas -{ - public: - LIST_HEAD (, mmap_list) lists; - - mmap_list *get_list_by_fd (int fd, struct __stat64 *st); - mmap_list *add_list (int fd, struct __stat64 *st); - void del_list (mmap_list *ml); -}; - -/* This is the global map structure pointer. */ -static mmap_areas mmapped_areas; - -bool -mmap_record::compatible_flags (int fl) const -{ -#define MAP_COMPATMASK (MAP_TYPE | MAP_NORESERVE) - return (get_flags () & MAP_COMPATMASK) == (fl & MAP_COMPATMASK); -} - -DWORD -mmap_record::find_unused_pages (DWORD pages) const -{ - DWORD mapped_pages = PAGE_CNT (get_len ()); - DWORD start; - - if (pages > mapped_pages) - return (DWORD)-1; - for (start = 0; start <= mapped_pages - pages; ++start) - if (!MAP_ISSET (start)) - { - DWORD cnt; - for (cnt = 0; cnt < pages; ++cnt) - if (MAP_ISSET (start + cnt)) - break; - if (cnt >= pages) - return start; - } - return (DWORD)-1; -} - -bool -mmap_record::match (caddr_t addr, DWORD len, caddr_t &m_addr, DWORD &m_len) -{ - caddr_t low = (addr >= get_address ()) ? addr : get_address (); - caddr_t high = get_address (); - if (filler ()) - high += get_len (); - else - high += (PAGE_CNT (get_len ()) * getsystempagesize ()); - high = (addr + len < high) ? addr + len : high; - if (low < high) - { - m_addr = low; - m_len = high - low; - return true; - } - return false; -} - -bool -mmap_record::alloc_page_map () -{ - /* Allocate one bit per page */ - if (!(page_map = (DWORD *) ccalloc (HEAP_MMAP, - MAPSIZE (PAGE_CNT (get_len ())), - sizeof (DWORD)))) - return false; - - DWORD start_protect = gen_create_protect (); - DWORD real_protect = gen_protect (); - if (real_protect != start_protect && !noreserve () - && !VirtualProtect (get_address (), get_len (), - real_protect, &start_protect)) - system_printf ("Warning: VirtualProtect (addr: %p, len: 0x%x, " - "new_prot: 0x%x, old_prot: 0x%x), %E", - get_address (), get_len (), - real_protect, start_protect); - DWORD len = PAGE_CNT (get_len ()); - while (len-- > 0) - MAP_SET (len); - return true; -} - -_off64_t -mmap_record::map_pages (_off64_t off, DWORD len) -{ - /* Used ONLY if this mapping matches into the chunk of another already - performed mapping in a special case of MAP_ANON|MAP_PRIVATE. - - Otherwise it's job is now done by alloc_page_map(). */ - DWORD old_prot; - debug_printf ("map_pages (fd=%d, off=%D, len=%u)", get_fd (), off, len); - len = PAGE_CNT (len); - - if ((off = find_unused_pages (len)) == (DWORD)-1) - return 0L; - if (!noreserve () - && !VirtualProtect (get_address () + off * getsystempagesize (), - len * getsystempagesize (), gen_protect (), - &old_prot)) - { - __seterrno (); - return (_off64_t)-1; - } - - while (len-- > 0) - MAP_SET (off + len); - return off * getsystempagesize (); -} - -bool -mmap_record::map_pages (caddr_t addr, DWORD len) -{ - debug_printf ("map_pages (addr=%x, len=%u)", addr, len); - DWORD old_prot; - DWORD off = addr - get_address (); - off /= getsystempagesize (); - len = PAGE_CNT (len); - /* First check if the area is unused right now. */ - for (DWORD l = 0; l < len; ++l) - if (MAP_ISSET (off + l)) - { - set_errno (EINVAL); - return false; - } - if (!noreserve () - && !VirtualProtect (get_address () + off * getsystempagesize (), - len * getsystempagesize (), gen_protect (), - &old_prot)) - { - __seterrno (); - return false; - } - for (; len-- > 0; ++off) - MAP_SET (off); - return true; -} - -bool -mmap_record::unmap_pages (caddr_t addr, DWORD len) -{ - DWORD old_prot; - DWORD off = addr - get_address (); - if (noreserve () - && !VirtualFree (get_address () + off, len, MEM_DECOMMIT)) - debug_printf ("VirtualFree in unmap_pages () failed, %E"); - else if (!VirtualProtect (get_address () + off, len, PAGE_NOACCESS, - &old_prot)) - debug_printf ("VirtualProtect in unmap_pages () failed, %E"); - - off /= getsystempagesize (); - len = PAGE_CNT (len); - for (; len-- > 0; ++off) - MAP_CLR (off); - /* Return TRUE if all pages are free'd which may result in unmapping - the whole chunk. */ - for (len = MAPSIZE (PAGE_CNT (get_len ())); len > 0; ) - if (page_map[--len]) - return false; - return true; -} - -int -mmap_record::access (caddr_t address) -{ - if (address < get_address () || address >= get_address () + get_len ()) - return 0; - DWORD off = (address - get_address ()) / getsystempagesize (); - return MAP_ISSET (off); -} - -fhandler_base * -mmap_record::alloc_fh () -{ - if (anonymous ()) - { - fh_anonymous.set_io_handle (INVALID_HANDLE_VALUE); - fh_anonymous.set_access (GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE); - return &fh_anonymous; - } - - /* The file descriptor could have been closed or, even - worse, could have been reused for another file before - the call to fork(). This requires creating a fhandler - of the correct type to be sure to call the method of the - correct class. */ - fhandler_base *fh = build_fh_dev (get_device ()); - fh->set_access (get_openflags ()); - return fh; -} - -void -mmap_record::free_fh (fhandler_base *fh) -{ - if (!anonymous ()) - delete fh; -} - -mmap_record * -mmap_list::add_record (mmap_record r) -{ - mmap_record *rec = (mmap_record *) cmalloc (HEAP_MMAP, sizeof (mmap_record)); - if (!rec) - return NULL; - *rec = r; - if (!rec->alloc_page_map ()) - { - cfree (rec); - return NULL; - } - LIST_INSERT_HEAD (&recs, rec, mr_next); - return rec; -} - -void -mmap_list::set (int nfd, struct __stat64 *st) -{ - fd = nfd; - if (!anonymous ()) - { - /* The fd isn't sufficient since it could already be the fd of another - file. So we use the inode number as evaluated by fstat to identify - the file. */ - hash = st ? st->st_ino : (__ino64_t) 0; - } - LIST_INIT (&recs); -} - -bool -mmap_list::del_record (mmap_record *rec) -{ - rec->free_page_map (); - LIST_REMOVE (rec, mr_next); - cfree (rec); - /* Return true if the list is empty which allows the caller to remove - this list from the list of lists. */ - return !LIST_FIRST(&recs); -} - -caddr_t -mmap_list::try_map (void *addr, size_t len, int flags, _off64_t off) -{ - mmap_record *rec; - - if (off == 0 && !fixed (flags)) - { - /* If MAP_FIXED isn't given, check if this mapping matches into the - chunk of another already performed mapping. */ - DWORD plen = PAGE_CNT (len); - LIST_FOREACH (rec, &recs, mr_next) - if (rec->find_unused_pages (plen) != (DWORD) -1) - break; - if (rec && rec->compatible_flags (flags)) - { - if ((off = rec->map_pages (off, len)) == (_off64_t) -1) - return (caddr_t) MAP_FAILED; - return (caddr_t) rec->get_address () + off; - } - } - else if (fixed (flags)) - { - /* If MAP_FIXED is given, test if the requested area is in an - unmapped part of an still active mapping. This can happen - if a memory region is unmapped and remapped with MAP_FIXED. */ - caddr_t u_addr; - DWORD u_len; - - LIST_FOREACH (rec, &recs, mr_next) - if (rec->match ((caddr_t) addr, len, u_addr, u_len)) - break; - if (rec) - { - if (u_addr > (caddr_t) addr || u_addr + len < (caddr_t) addr + len - || !rec->compatible_flags (flags)) - { - /* Partial match only, or access mode doesn't match. */ - /* FIXME: Handle partial mappings gracefully if adjacent - memory is available. */ - set_errno (EINVAL); - return (caddr_t) MAP_FAILED; - } - if (!rec->map_pages ((caddr_t) addr, len)) - return (caddr_t) MAP_FAILED; - return (caddr_t) addr; - } - } - return NULL; -} - -mmap_list * -mmap_areas::get_list_by_fd (int fd, struct __stat64 *st) -{ - mmap_list *ml; - LIST_FOREACH (ml, &lists, ml_next) - { - if (fd == -1 && ml->anonymous ()) - return ml; - /* The fd isn't sufficient since it could already be the fd of another - file. So we use the inode number as evaluated by fstat to identify - the file. */ - if (fd != -1 && st && ml->get_hash () == st->st_ino) - return ml; - } - return 0; -} - -mmap_list * -mmap_areas::add_list (int fd, struct __stat64 *st) -{ - mmap_list *ml = (mmap_list *) cmalloc (HEAP_MMAP, sizeof (mmap_list)); - if (!ml) - return NULL; - ml->set (fd, st); - LIST_INSERT_HEAD (&lists, ml, ml_next); - return ml; -} - -void -mmap_areas::del_list (mmap_list *ml) -{ - LIST_REMOVE (ml, ml_next); - cfree (ml); -} - -/* This function is called from exception_handler when a segmentation - violation has occurred. It should also be called from all Cygwin - functions that want to support passing noreserve mmap page addresses - to Windows system calls. In that case, it should be called only after - a system call indicates that the application buffer passed had an - invalid virtual address to avoid any performance impact in non-noreserve - cases. - - Check if the address range is all within noreserve mmap regions. If so, - call VirtualAlloc to commit the pages and return MMAP_NORESERVE_COMMITED - on success. If the page has __PROT_ATTACH (SUSv3 memory protection - extension), or if VirutalAlloc fails, return MMAP_RAISE_SIGBUS. - Otherwise, return MMAP_NONE if the address range is not covered by an - attached or noreserve map. - - On MAP_NORESERVE_COMMITED, the exeception handler should return 0 to - allow the application to retry the memory access, or the calling Cygwin - function should retry the Windows system call. */ -mmap_region_status -mmap_is_attached_or_noreserve (void *addr, size_t len) -{ - mmap_region_status ret = MMAP_NONE; - - LIST_LOCK (); - mmap_list *map_list = mmapped_areas.get_list_by_fd (-1, NULL); - - size_t pagesize = getpagesize (); - caddr_t start_addr = (caddr_t) rounddown ((uintptr_t) addr, pagesize); - len += ((caddr_t) addr - start_addr); - len = roundup2 (len, pagesize); - - if (map_list == NULL) - goto out; - - mmap_record *rec; - caddr_t u_addr; - DWORD u_len; - - LIST_FOREACH (rec, &map_list->recs, mr_next) - { - if (!rec->match (start_addr, len, u_addr, u_len)) - continue; - if (rec->attached ()) - { - ret = MMAP_RAISE_SIGBUS; - break; - } - if (!rec->noreserve ()) - break; - - size_t commit_len = u_len - (start_addr - u_addr); - if (commit_len > len) - commit_len = len; - - if (!VirtualAlloc (start_addr, commit_len, MEM_COMMIT, - rec->gen_protect ())) - { - ret = MMAP_RAISE_SIGBUS; - break; - } - - start_addr += commit_len; - len -= commit_len; - if (!len) - { - ret = MMAP_NORESERVE_COMMITED; - break; - } - } -out: - LIST_UNLOCK (); - return ret; -} - -static caddr_t -mmap_worker (mmap_list *map_list, fhandler_base *fh, caddr_t base, size_t len, - int prot, int flags, int fd, _off64_t off, struct __stat64 *st) -{ - HANDLE h = fh->mmap (&base, len, prot, flags, off); - if (h == INVALID_HANDLE_VALUE) - return NULL; - if (!map_list - && !(map_list = mmapped_areas.get_list_by_fd (fd, st)) - && !(map_list = mmapped_areas.add_list (fd, st))) - { - fh->munmap (h, base, len); - return NULL; - } - mmap_record mmap_rec (fd, h, fh->get_access (), prot, flags, off, len, base); - mmap_record *rec = map_list->add_record (mmap_rec); - if (!rec) - { - fh->munmap (h, base, len); - return NULL; - } - return base; -} - -extern "C" void * -mmap64 (void *addr, size_t len, int prot, int flags, int fd, _off64_t off) -{ - syscall_printf ("addr %x, len %u, prot %x, flags %x, fd %d, off %D", - addr, len, prot, flags, fd, off); - - caddr_t ret = (caddr_t) MAP_FAILED; - fhandler_base *fh = NULL; - fhandler_disk_file *fh_disk_file = NULL; /* Used for reopening a disk file - when necessary. */ - mmap_list *map_list = NULL; - size_t orig_len = 0; - caddr_t base = NULL; - struct __stat64 st; - - DWORD pagesize = getpagesize (); - - fh_anonymous.set_io_handle (INVALID_HANDLE_VALUE); - fh_anonymous.set_access (GENERIC_READ | GENERIC_WRITE | GENERIC_EXECUTE); - - /* EINVAL error conditions. */ - if (off % pagesize - || ((prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))) - || ((flags & MAP_TYPE) != MAP_SHARED - && (flags & MAP_TYPE) != MAP_PRIVATE) - || (fixed (flags) && ((uintptr_t) addr % pagesize)) - || !len) - { - set_errno (EINVAL); - goto out; - } - - if (!anonymous (flags) && fd != -1) - { - /* Ensure that fd is open */ - cygheap_fdget cfd (fd); - if (cfd < 0) - goto out; - - fh = cfd; - - /* mmap /dev/zero is like MAP_ANONYMOUS. */ - if (fh->get_device () == FH_ZERO) - flags |= MAP_ANONYMOUS; - } - - if (anonymous (flags) || fd == -1) - { - fh = &fh_anonymous; - fd = -1; - flags |= MAP_ANONYMOUS; - /* Anonymous mappings are always forced to pagesize length with - no offset. */ - len = roundup2 (len, pagesize); - off = 0; - } - else if (fh->get_device () == FH_FS) - { - /* EACCES error conditions according to SUSv3. File must be opened - for reading, regardless of the requested protection, and file must - be opened for writing when PROT_WRITE together with MAP_SHARED - is requested. */ - if (!(fh->get_access () & GENERIC_READ) - || (!(fh->get_access () & GENERIC_WRITE) - && (prot & PROT_WRITE) && !priv (flags))) - { - set_errno (EACCES); - goto out; - } - - /* You can't create mappings with PAGE_EXECUTE protection if - the file isn't explicitely opened with EXECUTE access. */ - OBJECT_ATTRIBUTES attr; - NTSTATUS status; - HANDLE h; - IO_STATUS_BLOCK io; - - InitializeObjectAttributes (&attr, &ro_u_empty, fh->pc.objcaseinsensitive (), - fh->get_handle (), NULL); - status = NtOpenFile (&h, - fh->get_access () | GENERIC_EXECUTE | SYNCHRONIZE, - &attr, &io, FILE_SHARE_VALID_FLAGS, - FILE_SYNCHRONOUS_IO_NONALERT - | FILE_OPEN_FOR_BACKUP_INTENT); - if (NT_SUCCESS (status)) - { - fh_disk_file = new (ccalloc (HEAP_FHANDLER, 1, sizeof *fh_disk_file)) - fhandler_disk_file; - fh_disk_file->set_name (fh->pc); - fh_disk_file->set_io_handle (h); - fh_disk_file->set_access (fh->get_access () | GENERIC_EXECUTE); - fh = fh_disk_file; - } - else if (prot & PROT_EXEC) - { - /* TODO: To be or not to be... I'm opting for refusing this - mmap request rather than faking it, but that might break - some non-portable code. */ - set_errno (EACCES); - goto out; - } - - if (fh->fstat_fs (&st)) - { - __seterrno (); - goto out; - } - _off64_t fsiz = st.st_size; - - /* Don't allow file mappings beginning beyond EOF since Windows can't - handle that POSIX like, unless MAP_AUTOGROW flag is set, which - mimics Windows behaviour. */ - if (off >= fsiz && !autogrow (flags)) - { - /* Instead, it seems suitable to return an anonymous mapping of - the given size instead. Mapped addresses beyond EOF aren't - written back to the file anyway, so the handling is identical - to other pages beyond EOF. */ - fh = &fh_anonymous; - len = roundup2 (len, pagesize); - prot = PROT_READ | PROT_WRITE | __PROT_ATTACH; - flags &= MAP_FIXED; - flags |= MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE; - fd = -1; - off = 0; - goto go_ahead; - } - fsiz -= off; - /* We're creating the pages beyond EOF as reserved, anonymous pages. - Note that this isn't done in WOW64 environments since apparently - WOW64 does not support the AT_ROUND_TO_PAGE flag which is required - to get this right. Too bad. */ - if (!wincap.is_wow64 () - && ((len > fsiz && !autogrow (flags)) - || roundup2 (len, getsystempagesize ()) - < roundup2 (len, pagesize))) - orig_len = len; - if (len > fsiz) - { - if (autogrow (flags)) - { - /* Allow mapping beyond EOF if MAP_AUTOGROW flag is set. - Check if file has been opened for writing, otherwise - MAP_AUTOGROW is invalid. */ - if (!(fh->get_access () & GENERIC_WRITE)) - { - set_errno (EINVAL); - goto out; - } - } - else - /* Otherwise, don't map beyond EOF, since Windows would change - the file to the new length, in contrast to POSIX. */ - len = fsiz; - } - - /* If the requested offset + len is <= file size, drop MAP_AUTOGROW. - This simplifes fhandler::mmap's job. */ - if (autogrow (flags) && (off + len) <= fsiz) - flags &= ~MAP_AUTOGROW; - } - -go_ahead: - - /* MAP_NORESERVE is only supported on private anonymous mappings. - Remove that bit from flags so that later code doesn't have to - test all bits. */ - if (noreserve (flags) && (!anonymous (flags) || !priv (flags))) - flags &= ~MAP_NORESERVE; - - LIST_LOCK (); - map_list = mmapped_areas.get_list_by_fd (fd, &st); - - /* Test if an existing anonymous mapping can be recycled. */ - if (map_list && anonymous (flags)) - { - caddr_t tried = map_list->try_map (addr, len, flags, off); - /* try_map returns NULL if no map matched, otherwise it returns - a valid address, or MAP_FAILED in case of a fatal error. */ - if (tried) - { - ret = tried; - goto out_with_unlock; - } - } - - if (orig_len) - { - /* If the requested length is bigger than the file size, we try to - allocate an area of the full size first. This area is immediately - deallocated and the address we got is used as base address for the - subsequent real mappings. This ensures that we have enough space - for the whole thing. */ - orig_len = roundup2 (orig_len, pagesize); - PVOID newaddr = VirtualAlloc (addr, orig_len, MEM_TOP_DOWN | MEM_RESERVE, - PAGE_READWRITE); - if (!newaddr) - { - /* If addr is not NULL, but MAP_FIXED isn't given, allow the OS - to choose. */ - if (addr && !fixed (flags)) - newaddr = VirtualAlloc (NULL, orig_len, MEM_TOP_DOWN | MEM_RESERVE, - PAGE_READWRITE); - if (!newaddr) - { - __seterrno (); - goto out_with_unlock; - } - } - if (!VirtualFree (newaddr, 0, MEM_RELEASE)) - { - __seterrno (); - goto out_with_unlock; - } - addr = newaddr; - } - - base = mmap_worker (map_list, fh, (caddr_t) addr, len, prot, flags, fd, off, - &st); - if (!base) - goto out_with_unlock; - - if (orig_len) - { - /* If the requested length is bigger than the file size, the - remainder is created as anonymous mapping. Actually two - mappings are created, first the remainder from the file end to - the next 64K boundary as accessible pages with the same - protection as the file's pages, then as much pages as necessary - to accomodate the requested length, but as reserved pages which - raise a SIGBUS when trying to access them. AT_ROUND_TO_PAGE - and page protection on shared pages is only supported by 32 bit NT, - so don't even try on WOW64. This is accomplished by not setting - orig_len on WOW64 above. */ -#if 0 - orig_len = roundup2 (orig_len, pagesize); -#endif - len = roundup2 (len, getsystempagesize ()); - if (orig_len - len) - { - orig_len -= len; - size_t valid_page_len = orig_len % pagesize; - size_t sigbus_page_len = orig_len - valid_page_len; - - caddr_t at_base = base + len; - if (valid_page_len) - { - prot |= __PROT_FILLER; - flags &= MAP_SHARED | MAP_PRIVATE; - flags |= MAP_ANONYMOUS | MAP_FIXED; - at_base = mmap_worker (NULL, &fh_anonymous, at_base, - valid_page_len, prot, flags, -1, 0, NULL); - if (!at_base) - { - fh->munmap (fh->get_handle (), base, len); - set_errno (ENOMEM); - goto out_with_unlock; - } - at_base += valid_page_len; - } - if (sigbus_page_len) - { - prot = PROT_READ | PROT_WRITE | __PROT_ATTACH; - flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_FIXED; - at_base = mmap_worker (NULL, &fh_anonymous, at_base, - sigbus_page_len, prot, flags, -1, 0, NULL); - if (!at_base) - debug_printf ("Warning: Mapping beyond EOF failed, %E"); - } - } - } - - ret = base; - -out_with_unlock: - LIST_UNLOCK (); - -out: - - if (fh_disk_file) - { - NtClose (fh_disk_file->get_handle ()); - delete fh; - } - - syscall_printf ("%p = mmap() ", ret); - return ret; -} - -extern "C" void * -mmap (void *addr, size_t len, int prot, int flags, int fd, _off_t off) -{ - return mmap64 (addr, len, prot, flags, fd, (_off64_t)off); -} - -/* munmap () removes all mmapped pages between addr and addr+len. */ - -extern "C" int -munmap (void *addr, size_t len) -{ - syscall_printf ("munmap (addr %x, len %u)", addr, len); - - /* Error conditions according to SUSv3 */ - if (!addr || !len || check_invalid_virtual_addr (addr, len)) - { - set_errno (EINVAL); - return -1; - } - size_t pagesize = getpagesize (); - if (((uintptr_t) addr % pagesize) || !len) - { - set_errno (EINVAL); - return -1; - } - len = roundup2 (len, pagesize); - - LIST_LOCK (); - - /* Iterate through the map, unmap pages between addr and addr+len - in all maps. */ - mmap_list *map_list, *next_map_list; - LIST_FOREACH_SAFE (map_list, &mmapped_areas.lists, ml_next, next_map_list) - { - mmap_record *rec, *next_rec; - caddr_t u_addr; - DWORD u_len; - - LIST_FOREACH_SAFE (rec, &map_list->recs, mr_next, next_rec) - { - if (!rec->match ((caddr_t) addr, len, u_addr, u_len)) - continue; - if (rec->unmap_pages (u_addr, u_len)) - { - /* The whole record has been unmapped, so we now actually - unmap it from the system in full length... */ - fhandler_base *fh = rec->alloc_fh (); - fh->munmap (rec->get_handle (), - rec->get_address (), - rec->get_len ()); - rec->free_fh (fh); - - /* ...and delete the record. */ - if (map_list->del_record (rec)) - { - /* Yay, the last record has been removed from the list, - we can remove the list now, too. */ - mmapped_areas.del_list (map_list); - break; - } - } - } - } - - LIST_UNLOCK (); - syscall_printf ("0 = munmap(): %x", addr); - return 0; -} - -/* Sync file with memory. Ignore flags for now. */ - -extern "C" int -msync (void *addr, size_t len, int flags) -{ - int ret = -1; - mmap_list *map_list; - - syscall_printf ("msync (addr: %p, len %u, flags %x)", addr, len, flags); - - LIST_LOCK (); - - if (((uintptr_t) addr % getpagesize ()) - || (flags & ~(MS_ASYNC | MS_SYNC | MS_INVALIDATE)) - || ((flags & (MS_ASYNC | MS_SYNC)) == (MS_ASYNC | MS_SYNC))) - { - set_errno (EINVAL); - goto out; - } -#if 0 /* If I only knew why I did that... */ - len = roundup2 (len, getpagesize ()); -#endif - - /* Iterate through the map, looking for the mmapped area. - Error if not found. */ - LIST_FOREACH (map_list, &mmapped_areas.lists, ml_next) - { - mmap_record *rec; - LIST_FOREACH (rec, &map_list->recs, mr_next) - { - if (rec->access ((caddr_t) addr)) - { - /* Check whole area given by len. */ - for (DWORD i = getpagesize (); i < len; i += getpagesize ()) - if (!rec->access ((caddr_t) addr + i)) - { - set_errno (ENOMEM); - goto out; - } - fhandler_base *fh = rec->alloc_fh (); - ret = fh->msync (rec->get_handle (), (caddr_t) addr, len, flags); - rec->free_fh (fh); - goto out; - } - } - } - - /* No matching mapping exists. */ - set_errno (ENOMEM); - -out: - LIST_UNLOCK (); - syscall_printf ("%d = msync()", ret); - return ret; -} - -/* Set memory protection */ - -extern "C" int -mprotect (void *addr, size_t len, int prot) -{ - bool in_mapped = false; - bool ret = false; - DWORD old_prot; - DWORD new_prot = 0; - - syscall_printf ("mprotect (addr: %p, len %u, prot %x)", addr, len, prot); - - /* See comment in mmap64 for a description. */ - size_t pagesize = getpagesize (); - if ((uintptr_t) addr % pagesize) - { - set_errno (EINVAL); - goto out; - } - len = roundup2 (len, pagesize); - - LIST_LOCK (); - - /* Iterate through the map, protect pages between addr and addr+len - in all maps. */ - mmap_list *map_list; - LIST_FOREACH (map_list, &mmapped_areas.lists, ml_next) - { - mmap_record *rec; - caddr_t u_addr; - DWORD u_len; - - LIST_FOREACH (rec, &map_list->recs, mr_next) - { - if (!rec->match ((caddr_t) addr, len, u_addr, u_len)) - continue; - in_mapped = true; - if (rec->attached ()) - continue; - new_prot = gen_protect (prot, rec->get_flags ()); - if (rec->noreserve ()) - { - if (new_prot == PAGE_NOACCESS) - ret = VirtualFree (u_addr, u_len, MEM_DECOMMIT); - else - ret = !!VirtualAlloc (u_addr, u_len, MEM_COMMIT, new_prot); - } - else - ret = VirtualProtect (u_addr, u_len, new_prot, &old_prot); - if (!ret) - { - __seterrno (); - break; - } - } - } - - LIST_UNLOCK (); - - if (!in_mapped) - { - int flags = 0; - MEMORY_BASIC_INFORMATION mbi; - - ret = VirtualQuery (addr, &mbi, sizeof mbi); - if (ret) - { - /* If write protection is requested, check if the page was - originally protected writecopy. In this case call VirtualProtect - requesting PAGE_WRITECOPY, otherwise the VirtualProtect will fail - on NT version >= 5.0 */ - if (prot & PROT_WRITE) - { - if (mbi.AllocationProtect == PAGE_WRITECOPY - || mbi.AllocationProtect == PAGE_EXECUTE_WRITECOPY) - flags = MAP_PRIVATE; - } - new_prot = gen_protect (prot, flags); - if (new_prot != PAGE_NOACCESS && mbi.State == MEM_RESERVE) - ret = VirtualAlloc (addr, len, MEM_COMMIT, new_prot); - else - ret = VirtualProtect (addr, len, new_prot, &old_prot); - } - if (!ret) - __seterrno (); - } - -out: - - syscall_printf ("%d = mprotect ()", ret ? 0 : -1); - return ret ? 0 : -1; -} - -extern "C" int -mlock (const void *addr, size_t len) -{ - int ret = -1; - - /* Instead of using VirtualLock, which does not guarantee that the pages - aren't swapped out when the process is inactive, we're using - ZwLockVirtualMemory with the LOCK_VM_IN_RAM flag to do what mlock on - POSIX systems does. On NT, this requires SeLockMemoryPrivilege, - which is given only to SYSTEM by default. */ - - push_thread_privilege (SE_LOCK_MEMORY_PRIVILEGE, true); - - /* Align address and length values to page size. */ - size_t pagesize = getpagesize (); - PVOID base = (PVOID) rounddown((uintptr_t) addr, pagesize); - ULONG size = roundup2 (((uintptr_t) addr - (uintptr_t) base) + len, pagesize); - NTSTATUS status = 0; - do - { - status = NtLockVirtualMemory (NtCurrentProcess (), &base, &size, - LOCK_VM_IN_RAM); - if (status == STATUS_WORKING_SET_QUOTA) - { - /* The working set is too small, try to increase it so that the - requested locking region fits in. Unfortunately I don't know - any function which would return the currently locked pages of - a process (no go with NtQueryVirtualMemory). - - So, except for the border cases, what we do here is something - really embarrassing. We raise the working set by 64K at a time - and retry, until either we fail to raise the working set size - further, or until NtLockVirtualMemory returns successfully (or - with another error). */ - ULONG min, max; - if (!GetProcessWorkingSetSize (GetCurrentProcess (), &min, &max)) - { - set_errno (ENOMEM); - break; - } - if (min < size) - min = size + pagesize; - else if (size < pagesize) - min += size; - else - min += pagesize; - if (max < min) - max = min; - if (!SetProcessWorkingSetSize (GetCurrentProcess (), min, max)) - { - set_errno (ENOMEM); - break; - } - } - else if (!NT_SUCCESS (status)) - __seterrno_from_nt_status (status); - else - ret = 0; - } - while (status == STATUS_WORKING_SET_QUOTA); - - pop_thread_privilege (); - - return ret; -} - -extern "C" int -munlock (const void *addr, size_t len) -{ - int ret = -1; - - push_thread_privilege (SE_LOCK_MEMORY_PRIVILEGE, true); - - /* Align address and length values to page size. */ - size_t pagesize = getpagesize (); - PVOID base = (PVOID) rounddown((uintptr_t) addr, pagesize); - ULONG size = roundup2 (((uintptr_t) addr - (uintptr_t) base) + len, pagesize); - NTSTATUS status = NtUnlockVirtualMemory (NtCurrentProcess (), &base, &size, - LOCK_VM_IN_RAM); - if (!NT_SUCCESS (status)) - __seterrno_from_nt_status (status); - else - ret = 0; - - pop_thread_privilege (); - - return ret; -} - -extern "C" int -posix_madvise (void *addr, size_t len, int advice) -{ - /* Check parameters. */ - if (advice < POSIX_MADV_NORMAL || advice > POSIX_MADV_DONTNEED - || !len) - return EINVAL; - - /* Check requested memory area. */ - MEMORY_BASIC_INFORMATION m; - char *p = (char *) addr; - char *endp = p + len; - while (p < endp) - { - if (!VirtualQuery (p, &m, sizeof m) || m.State == MEM_FREE) - return ENOMEM; - p = (char *) m.BaseAddress + m.RegionSize; - } - - /* Eventually do nothing. */ - return 0; -} - -/* - * Base implementation: - * - * `mmap' returns ENODEV as documented in SUSv2. - * In contrast to the global function implementation, the member function - * `mmap' has to return the mapped base address in `addr' and the handle to - * the mapping object as return value. In case of failure, the fhandler - * mmap has to close that handle by itself and return INVALID_HANDLE_VALUE. - * - * `munmap' and `msync' get the handle to the mapping object as first parameter - * additionally. -*/ -HANDLE -fhandler_base::mmap (caddr_t *addr, size_t len, int prot, - int flags, _off64_t off) -{ - set_errno (ENODEV); - return INVALID_HANDLE_VALUE; -} - -int -fhandler_base::munmap (HANDLE h, caddr_t addr, size_t len) -{ - set_errno (ENODEV); - return -1; -} - -int -fhandler_base::msync (HANDLE h, caddr_t addr, size_t len, int flags) -{ - set_errno (ENODEV); - return -1; -} - -bool -fhandler_base::fixup_mmap_after_fork (HANDLE h, int prot, int flags, - _off64_t offset, DWORD size, - void *address) -{ - set_errno (ENODEV); - return -1; -} - -/* Implementation for anonymous maps. Using fhandler_dev_zero looks - quite the natural way. */ -HANDLE -fhandler_dev_zero::mmap (caddr_t *addr, size_t len, int prot, - int flags, _off64_t off) -{ - HANDLE h; - void *base; - - if (priv (flags) && !filler (prot)) - { - /* Private anonymous maps are now implemented using VirtualAlloc. - This has two advantages: - - - VirtualAlloc has a smaller footprint than a copy-on-write - anonymous map. - - - It supports decommitting using VirtualFree, in contrast to - section maps. This allows minimum footprint private maps, - when using the (non-POSIX, yay-Linux) MAP_NORESERVE flag. - */ - DWORD protect = gen_protect (prot, flags); - DWORD alloc_type = MEM_TOP_DOWN | MEM_RESERVE - | (noreserve (flags) ? 0 : MEM_COMMIT); - base = VirtualAlloc (*addr, len, alloc_type, protect); - if (!base && addr && !fixed (flags)) - base = VirtualAlloc (NULL, len, alloc_type, protect); - if (!base || (fixed (flags) && base != *addr)) - { - if (!base) - __seterrno (); - else - { - VirtualFree (base, 0, MEM_RELEASE); - set_errno (EINVAL); - debug_printf ("VirtualAlloc: address shift with MAP_FIXED given"); - } - return INVALID_HANDLE_VALUE; - } - h = (HANDLE) 1; /* Fake handle to indicate success. */ - } - else - { - h = CreateMapping (get_handle (), len, off, get_access (), prot, flags); - if (!h) - { - __seterrno (); - debug_printf ("CreateMapping failed with %E"); - return INVALID_HANDLE_VALUE; - } - - base = MapView (h, *addr, len, get_access(), prot, flags, off); - if (!base || (fixed (flags) && base != *addr)) - { - if (!base) - __seterrno (); - else - { - NtUnmapViewOfSection (NtCurrentProcess (), base); - set_errno (EINVAL); - debug_printf ("MapView: address shift with MAP_FIXED given"); - } - NtClose (h); - return INVALID_HANDLE_VALUE; - } - } - *addr = (caddr_t) base; - return h; -} - -int -fhandler_dev_zero::munmap (HANDLE h, caddr_t addr, size_t len) -{ - if (h == (HANDLE) 1) /* See fhandler_dev_zero::mmap. */ - VirtualFree (addr, 0, MEM_RELEASE); - else - { - NtUnmapViewOfSection (NtCurrentProcess (), addr); - NtClose (h); - } - return 0; -} - -int -fhandler_dev_zero::msync (HANDLE h, caddr_t addr, size_t len, int flags) -{ - return 0; -} - -bool -fhandler_dev_zero::fixup_mmap_after_fork (HANDLE h, int prot, int flags, - _off64_t offset, DWORD size, - void *address) -{ - /* Re-create the map */ - void *base; - if (priv (flags) && !filler (prot)) - { - DWORD alloc_type = MEM_RESERVE | (noreserve (flags) ? 0 : MEM_COMMIT); - /* Always allocate R/W so that ReadProcessMemory doesn't fail - due to a non-writable target address. The protection is - set to the correct one anyway in the fixup loop. */ - base = VirtualAlloc (address, size, alloc_type, PAGE_READWRITE); - } - else - base = MapView (h, address, size, get_access (), prot, flags, offset); - if (base != address) - { - MEMORY_BASIC_INFORMATION m; - VirtualQuery (address, &m, sizeof (m)); - system_printf ("requested %p != %p mem alloc base %p, state %p, " - "size %d, %E", address, base, m.AllocationBase, m.State, - m.RegionSize); - } - return base == address; -} - -/* Implementation for disk files and anonymous mappings. */ -HANDLE -fhandler_disk_file::mmap (caddr_t *addr, size_t len, int prot, - int flags, _off64_t off) -{ - HANDLE h = CreateMapping (get_handle (), len, off, get_access (), - prot, flags); - if (!h) - { - __seterrno (); - debug_printf ("CreateMapping failed with %E"); - return INVALID_HANDLE_VALUE; - } - - void *base = MapView (h, *addr, len, get_access (), prot, flags, off); - if (!base || (fixed (flags) && base != *addr)) - { - if (!base) - __seterrno (); - else - { - NtUnmapViewOfSection (NtCurrentProcess (), base); - set_errno (EINVAL); - debug_printf ("MapView: address shift with MAP_FIXED given"); - } - NtClose (h); - return INVALID_HANDLE_VALUE; - } - - *addr = (caddr_t) base; - return h; -} - -int -fhandler_disk_file::munmap (HANDLE h, caddr_t addr, size_t len) -{ - NtUnmapViewOfSection (NtCurrentProcess (), addr); - NtClose (h); - return 0; -} - -int -fhandler_disk_file::msync (HANDLE h, caddr_t addr, size_t len, int flags) -{ - if (FlushViewOfFile (addr, len) == 0) - { - __seterrno (); - return -1; - } - return 0; -} - -bool -fhandler_disk_file::fixup_mmap_after_fork (HANDLE h, int prot, int flags, - _off64_t offset, DWORD size, - void *address) -{ - /* Re-create the map */ - void *base = MapView (h, address, size, get_access (), prot, flags, offset); - if (base != address) - { - MEMORY_BASIC_INFORMATION m; - VirtualQuery (address, &m, sizeof (m)); - system_printf ("requested %p != %p mem alloc base %p, state %p, " - "size %d, %E", address, base, m.AllocationBase, m.State, - m.RegionSize); - } - return base == address; -} - -HANDLE -fhandler_dev_mem::mmap (caddr_t *addr, size_t len, int prot, - int flags, _off64_t off) -{ - if (off >= mem_size - || (DWORD) len >= mem_size - || off + len >= mem_size) - { - set_errno (EINVAL); - debug_printf ("-1 = mmap(): illegal parameter, set EINVAL"); - return INVALID_HANDLE_VALUE; - } - - OBJECT_ATTRIBUTES attr; - InitializeObjectAttributes (&attr, &ro_u_pmem, - OBJ_CASE_INSENSITIVE | OBJ_INHERIT, - NULL, NULL); - - /* Section access is bit-wise ored, while on the Win32 level access - is only one of the values. It's not quite clear if the section - access has to be defined this way, or if SECTION_ALL_ACCESS would - be sufficient but this worked fine so far, so why change? */ - ACCESS_MASK section_access; - if (prot & PROT_WRITE) - section_access = SECTION_MAP_READ | SECTION_MAP_WRITE; - else - section_access = SECTION_MAP_READ; - - HANDLE h; - NTSTATUS ret = NtOpenSection (&h, section_access, &attr); - if (!NT_SUCCESS (ret)) - { - __seterrno_from_nt_status (ret); - debug_printf ("-1 = mmap(): NtOpenSection failed with %E"); - return INVALID_HANDLE_VALUE; - } - - void *base = MapView (h, *addr, len, get_access (), prot, - flags | MAP_ANONYMOUS, off); - if (!base || (fixed (flags) && base != *addr)) - { - if (!base) - __seterrno (); - else - { - NtUnmapViewOfSection (NtCurrentProcess (), base); - set_errno (EINVAL); - debug_printf ("MapView: address shift with MAP_FIXED given"); - } - NtClose (h); - return INVALID_HANDLE_VALUE; - } - - *addr = (caddr_t) base; - return h; -} - -int -fhandler_dev_mem::munmap (HANDLE h, caddr_t addr, size_t len) -{ - NTSTATUS ret; - if (!NT_SUCCESS (ret = NtUnmapViewOfSection (NtCurrentProcess (), addr))) - { - __seterrno_from_nt_status (ret); - return -1; - } - NtClose (h); - return 0; -} - -int -fhandler_dev_mem::msync (HANDLE h, caddr_t addr, size_t len, int flags) -{ - return 0; -} - -bool -fhandler_dev_mem::fixup_mmap_after_fork (HANDLE h, int prot, int flags, - _off64_t offset, DWORD size, - void *address) -{ - void *base = MapView (h, address, size, get_access (), prot, - flags | MAP_ANONYMOUS, offset); - if (base != address) - { - MEMORY_BASIC_INFORMATION m; - VirtualQuery (address, &m, sizeof (m)); - system_printf ("requested %p != %p mem alloc base %p, state %p, " - "size %d, %E", address, base, m.AllocationBase, m.State, - m.RegionSize); - } - return base == address; -} - -/* Call to re-create all the file mappings in a forked child. Called from - the child in initialization. At this point we are passed a valid - mmapped_areas map, and all the HANDLE's are valid for the child, but - none of the mapped areas are in our address space. We need to iterate - through the map, doing the MapViewOfFile calls. */ - -int __stdcall -fixup_mmaps_after_fork (HANDLE parent) -{ - /* Iterate through the map */ - mmap_list *map_list; - LIST_FOREACH (map_list, &mmapped_areas.lists, ml_next) - { - mmap_record *rec; - LIST_FOREACH (rec, &map_list->recs, mr_next) - { - debug_printf ("fd %d, h 0x%x, address %p, len 0x%x, prot: 0x%x, " - "flags: 0x%x, offset %X", - rec->get_fd (), rec->get_handle (), rec->get_address (), - rec->get_len (), rec->get_prot (), rec->get_flags (), - rec->get_offset ()); - - fhandler_base *fh = rec->alloc_fh (); - bool ret = fh->fixup_mmap_after_fork (rec->get_handle (), - rec->get_prot (), - rec->get_flags () | MAP_FIXED, - rec->get_offset (), - rec->get_len (), - rec->get_address ()); - rec->free_fh (fh); - - if (!ret) - { - if (rec->attached ()) - { - system_printf ("Warning: Fixup mapping beyond EOF failed"); - continue; - } - return -1; - } - - MEMORY_BASIC_INFORMATION mbi; - DWORD old_prot; - - for (char *address = rec->get_address (); - address < rec->get_address () + rec->get_len (); - address += mbi.RegionSize) - { - if (!VirtualQueryEx (parent, address, &mbi, sizeof mbi)) - { - system_printf ("VirtualQueryEx failed for MAP_PRIVATE " - "address %p, %E", address); - return -1; - } - /* Just skip reserved pages. */ - if (mbi.State == MEM_RESERVE) - continue; - /* Copy-on-write pages must be copied to the child to circumvent - a strange notion how copy-on-write is supposed to work. */ - if (rec->priv ()) - { - if (rec->noreserve () - && !VirtualAlloc (address, mbi.RegionSize, - MEM_COMMIT, PAGE_READWRITE)) - { - system_printf ("VirtualAlloc failed for MAP_PRIVATE " - "address %p, %E", address); - return -1; - } - if (mbi.Protect == PAGE_NOACCESS - && !VirtualProtectEx (parent, address, mbi.RegionSize, - PAGE_READONLY, &old_prot)) - { - system_printf ("VirtualProtectEx failed for MAP_PRIVATE " - "address %p, %E", address); - return -1; - } - else if ((mbi.AllocationProtect == PAGE_WRITECOPY - || mbi.AllocationProtect == PAGE_EXECUTE_WRITECOPY) - && (mbi.Protect == PAGE_READWRITE - || mbi.Protect == PAGE_EXECUTE_READWRITE)) - /* A WRITECOPY page which has been written to is set to - READWRITE, but that's an incompatible protection to - set the page to. Convert the protection to WRITECOPY - so that the below VirtualProtect doesn't fail. */ - mbi.Protect <<= 1; - - if (!ReadProcessMemory (parent, address, address, - mbi.RegionSize, NULL)) - { - system_printf ("ReadProcessMemory failed for MAP_PRIVATE " - "address %p, %E", address); - return -1; - } - if (mbi.Protect == PAGE_NOACCESS - && !VirtualProtectEx (parent, address, mbi.RegionSize, - PAGE_NOACCESS, &old_prot)) - { - system_printf ("WARNING: VirtualProtectEx to return to " - "PAGE_NOACCESS state in parent failed for " - "MAP_PRIVATE address %p, %E", address); - return -1; - } - } - /* Set child page protection to parent protection */ - if (!VirtualProtect (address, mbi.RegionSize, - mbi.Protect, &old_prot)) - { - MEMORY_BASIC_INFORMATION m; - VirtualQuery (address, &m, sizeof m); - system_printf ("VirtualProtect failed for " - "address %p, " - "parentstate: 0x%x, " - "state: 0x%x, " - "parentprot: 0x%x, " - "prot: 0x%x, %E", - address, mbi.State, m.State, - mbi.Protect, m.Protect); - return -1; - } - } - } - } - - debug_printf ("succeeded"); - return 0; -} |