/*
* UCW Library -- Mapping of File Parts
*
- * (c) 2003 Martin Mares <mj@ucw.cz>
- * (c) 2003 Robert Spalek <robert@ucw.cz>
+ * (c) 2003--2006 Martin Mares <mj@ucw.cz>
+ * (c) 2003--2005 Robert Spalek <robert@ucw.cz>
*
* This software may be freely distributed and used according to the terms
* of the GNU Lesser General Public License.
#include "lib/lib.h"
#include "lib/lfs.h"
+#include "lib/partmap.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/mman.h>
-#include <sys/user.h>
-
-struct partmap {
- int fd;
- sh_off_t file_size;
- sh_off_t start_off, end_off;
- byte *start_map;
- int writeable;
-};
+#ifdef CONFIG_PARTMAP_IS_MMAP
+#define PARTMAP_WINDOW ~(size_t)0
+#else
#ifdef TEST
#define PARTMAP_WINDOW 4096
#else
#define PARTMAP_WINDOW 16777216
#endif
+#endif
struct partmap *
-partmap_open(byte *name, int writeable)
+partmap_open(char *name, int writeable)
{
struct partmap *p = xmalloc_zero(sizeof(struct partmap));
if ((p->file_size = sh_seek(p->fd, 0, SEEK_END)) < 0)
die("lseek(%s): %m", name);
p->writeable = writeable;
+#ifdef CONFIG_PARTMAP_IS_MMAP
+ partmap_load(p, 0, p->file_size);
+#endif
return p;
}
xfree(p);
}
-void *
-partmap_map(struct partmap *p, sh_off_t start, uns size)
+void
+partmap_load(struct partmap *p, sh_off_t start, uns size)
{
- if (unlikely(!p->start_map || start < p->start_off || (sh_off_t) (start+size) > p->end_off))
- {
- if (p->start_map)
- munmap(p->start_map, p->end_off - p->start_off);
- sh_off_t end = start + size;
- sh_off_t win_start = start/PAGE_SIZE * PAGE_SIZE;
- uns win_len = PARTMAP_WINDOW;
- if ((sh_off_t) (win_start+win_len) > p->file_size)
- win_len = ALIGN(p->file_size - win_start, PAGE_SIZE);
- if ((sh_off_t) (win_start+win_len) < end)
- die("partmap_map: Window is too small for mapping %d bytes", size);
- p->start_map = sh_mmap(NULL, win_len, p->writeable ? (PROT_READ | PROT_WRITE) : PROT_READ, MAP_SHARED, p->fd, win_start);
- if (p->start_map == MAP_FAILED)
- die("mmap failed at position %Ld: %m", (long long)win_start);
- p->start_off = win_start;
- p->end_off = win_start+win_len;
- }
- return p->start_map + (start - p->start_off);
+ if (p->start_map)
+ munmap(p->start_map, p->end_off - p->start_off);
+ sh_off_t end = start + size;
+ sh_off_t win_start = start/CPU_PAGE_SIZE * CPU_PAGE_SIZE;
+ size_t win_len = PARTMAP_WINDOW;
+ if ((sh_off_t) (win_start+win_len) > p->file_size)
+ win_len = ALIGN_TO(p->file_size - win_start, CPU_PAGE_SIZE);
+ if ((sh_off_t) (win_start+win_len) < end)
+ die("partmap_map: Window is too small for mapping %d bytes", size);
+ p->start_map = sh_mmap(NULL, win_len, p->writeable ? (PROT_READ | PROT_WRITE) : PROT_READ, MAP_SHARED, p->fd, win_start);
+ if (p->start_map == MAP_FAILED)
+ die("mmap failed at position %lld: %m", (long long)win_start);
+ p->start_off = win_start;
+ p->end_off = win_start+win_len;
+ madvise(p->start_map, win_len, MADV_SEQUENTIAL);
}
#ifdef TEST