Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com */
#include "src/internal_config.h"
-#if HAVE_UNISTD_H
-#include <unistd.h> /* Prototypes for lseek */
-#endif
#include <stdio.h>
#include <fcntl.h>
#include <sys/mman.h>
#define PAGE_ALIGN(addr) (void*) (((long)(addr) + xbt_pagesize - 1) & \
~((long)xbt_pagesize - 1))
-/* Return MAP_PRIVATE if MDP represents /dev/zero. Otherwise, return
- MAP_SHARED. */
-#define MAP_PRIVATE_OR_SHARED(MDP) (( MDP -> flags & MMALLOC_ANONYMOUS) \
- ? MAP_PRIVATE \
- : MAP_SHARED)
-
-/* Return MAP_ANONYMOUS if MDP uses anonymous mapping. Otherwise, return 0 */
-#define MAP_IS_ANONYMOUS(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
- ? MAP_ANONYMOUS \
- : 0)
-
-/* Return -1 if MDP uses anonymous mapping. Otherwise, return MDP->FD */
-#define MAP_ANON_OR_FD(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
- ? -1 \
- : (MDP) -> fd)
-
-/* Return 0if MDP uses anonymous mapping. Otherwise, return off */
-#define MAP_ANON_OR_OFFSET(MDP, off) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
- ? 0 \
- : off)
-
/** @brief Add memory to this heap
*
* Get core for the memory region specified by MDP, using SIZE as the
void *mmorecore(struct mdesc *mdp, ssize_t size)
{
void* result; // please keep it uninitialized to track issues
- off_t foffset; /* File offset at which new mapping will start */
size_t mapbytes; /* Number of bytes to map */
void* moveto; /* Address where we wish to move "break value" to */
void* mapto; /* Address we actually mapped to */
- char buf = 0; /* Single byte to write to extend mapped file */
if (size == 0) {
/* Just return the current "break" value. */
fprintf(stderr,"Internal error: mmap was asked to deallocate more memory than it previously allocated. Bailling out now!\n");
abort();
}
- } else {
- /* We are allocating memory. Make sure we have an open file descriptor if not working with anonymous memory. */
- if (!(mdp->flags & MMALLOC_ANONYMOUS) && mdp->fd < 0) {
- fprintf(stderr,"Internal error: mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags.\n",mdp->fd);
+ } else if ((char*)mdp->breakval + size > (char*)mdp->top) {
+ /* The request would move us past the end of the currently mapped memory, so map in enough more memory to satisfy
+ the request. This means we also have to grow the mapped-to file by an appropriate amount, since mmap cannot
+ be used to extend a file. */
+ moveto = PAGE_ALIGN((char*)mdp->breakval + size);
+ mapbytes = (char*)moveto - (char*)mdp->top;
+
+ /* Let's call mmap. Note that it is possible that mdp->top is 0. In this case mmap will choose the address for us.
+ This call might very well overwrite an already existing memory mapping (leading to weird bugs).
+ */
+ mapto = mmap(mdp->top, mapbytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+
+ if (mapto == MAP_FAILED) {
+ char buff[1024];
+ fprintf(stderr, "Internal error: mmap returned MAP_FAILED! error: %s\n", strerror(errno));
+ snprintf(buff, 1024, "cat /proc/%d/maps", getpid());
+ int status = system(buff);
+ if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0))
+ fprintf(stderr, "Something went wrong when trying to %s\n", buff);
+ sleep(1);
abort();
- } else if ((char*)mdp->breakval + size > (char*)mdp->top) {
- /* The request would move us past the end of the currently mapped memory, so map in enough more memory to satisfy
- the request. This means we also have to grow the mapped-to file by an appropriate amount, since mmap cannot
- be used to extend a file. */
- moveto = PAGE_ALIGN((char*)mdp->breakval + size);
- mapbytes = (char*)moveto - (char*)mdp->top;
- foffset = (char*)mdp->top - (char*)mdp->base;
-
- if (mdp->fd > 0) {
- if (lseek(mdp->fd, foffset + mapbytes - 1, SEEK_SET) == -1) {
- fprintf(stderr, "Internal error: lseek into mmap'ed fd failed! error: %s", strerror(errno));
- abort();
- }
- if (write(mdp->fd, &buf, 1) == -1) {
- fprintf(stderr,"Internal error: write to mmap'ed fd failed! error: %s", strerror(errno));
- abort();
- }
- }
-
- /* Let's call mmap. Note that it is possible that mdp->top is 0. In this case mmap will choose the address for us.
- This call might very well overwrite an already existing memory mapping (leading to weird bugs).
- */
- mapto = mmap(mdp->top, mapbytes, PROT_READ | PROT_WRITE,
- MAP_PRIVATE_OR_SHARED(mdp) | MAP_IS_ANONYMOUS(mdp) |
- MAP_FIXED, MAP_ANON_OR_FD(mdp), MAP_ANON_OR_OFFSET(mdp, foffset));
-
- if (mapto == MAP_FAILED) {
- char buff[1024];
- fprintf(stderr,"Internal error: mmap returned MAP_FAILED! error: %s\n",strerror(errno));
- snprintf(buff,1024,"cat /proc/%d/maps",getpid());
- int status = system(buff);
- if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0))
- fprintf(stderr, "Something went wrong when trying to %s\n", buff);
- sleep(1);
- abort();
- }
+ }
- if (mdp->top == 0)
- mdp->base = mdp->breakval = mapto;
+ if (mdp->top == 0)
+ mdp->base = mdp->breakval = mapto;
- mdp->top = PAGE_ALIGN((char*)mdp->breakval + size);
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- } else {
- /* Memory is already mapped, we only need to increase the breakval: */
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- }
+ mdp->top = PAGE_ALIGN((char*)mdp->breakval + size);
+ result = mdp->breakval;
+ mdp->breakval = (char*)mdp->breakval + size;
+ } else {
+ /* Memory is already mapped, we only need to increase the breakval: */
+ result = mdp->breakval;
+ mdp->breakval = (char*)mdp->breakval + size;
}
return result;
}
-
-void* __mmalloc_remap_core(const s_xbt_mheap_t* mdp)
-{
- /* FIXME: Quick hack, needs error checking and other attention. */
-
- return mmap(mdp->base, (char*) mdp->top - (char*) mdp->base,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE_OR_SHARED(mdp) | MAP_FIXED, mdp->fd, 0);
-}
-
