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Clean up locarchive mmap reservation code.

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Roland McGrath 2011-09-19 11:32:27 -07:00 committed by Roland McGrath
parent 5060422095
commit 110946e473
2 changed files with 35 additions and 42 deletions
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3
ChangeLog
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@ -1,5 +1,8 @@
2011-10-08 Roland McGrath <roland@hack.frob.com>
* locale/programs/locarchive.c (prepare_address_space): New function.
(create_archive, enlarge_archive, open_archive): Use it.
* sysdeps/unix/sysv/linux/x86_64/time.c: Move #include <dl-vdso.h>
inside [SHARED], where it is used.

74
locale/programs/locarchive.c
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@ -74,6 +74,29 @@ static const char *locnames[] =
/* Size of the reserved address space area. */
#define RESERVE_MMAP_SIZE 512 * 1024 * 1024
/* To prepare for enlargements of the mmaped area reserve some address
space. On some machines, being a file mapping rather than an anonymous
mapping affects the address selection. So do this mapping from the
actual file, even though it's only a dummy to reserve address space. */
static void *
prepare_address_space (int fd, size_t total, size_t *reserved, int *xflags)
{
if (total < RESERVE_MMAP_SIZE)
{
void *p = mmap64 (NULL, RESERVE_MMAP_SIZE, PROT_NONE, MAP_SHARED, fd, 0);
if (p != MAP_FAILED)
{
*reserved = RESERVE_MMAP_SIZE;
*xflags = MAP_FIXED;
return p;
}
}
*reserved = total;
*xflags = 0;
return NULL;
}
static void
create_archive (const char *archivefname, struct locarhandle *ah)
@ -81,7 +104,6 @@ create_archive (const char *archivefname, struct locarhandle *ah)
int fd;
char fname[strlen (archivefname) + sizeof (".XXXXXX")];
struct locarhead head;
void *p;
size_t total;
strcpy (stpcpy (fname, archivefname), ".XXXXXX");
@ -129,19 +151,9 @@ create_archive (const char *archivefname, struct locarhandle *ah)
error (EXIT_FAILURE, errval, _("cannot resize archive file"));
}
/* To prepare for enlargements of the mmaped area reserve some
address space. */
size_t reserved = RESERVE_MMAP_SIZE;
int xflags = 0;
if (total < reserved
&& ((p = mmap64 (NULL, reserved, PROT_NONE, MAP_PRIVATE | MAP_ANON,
-1, 0)) != MAP_FAILED))
xflags = MAP_FIXED;
else
{
p = NULL;
reserved = total;
}
size_t reserved;
int xflags;
void *p = prepare_address_space (fd, total, &reserved, &xflags);
/* Map the header and all the administration data structures. */
p = mmap64 (p, total, PROT_READ | PROT_WRITE, MAP_SHARED | xflags, fd, 0);
@ -297,7 +309,6 @@ enlarge_archive (struct locarhandle *ah, const struct locarhead *head)
int fd;
struct locarhead newhead;
size_t total;
void *p;
unsigned int cnt, loccnt;
struct namehashent *oldnamehashtab;
struct locarhandle new_ah;
@ -390,19 +401,9 @@ enlarge_archive (struct locarhandle *ah, const struct locarhead *head)
error (EXIT_FAILURE, errval, _("cannot resize archive file"));
}
/* To prepare for enlargements of the mmaped area reserve some
address space. */
size_t reserved = RESERVE_MMAP_SIZE;
int xflags = 0;
if (total < reserved
&& ((p = mmap64 (NULL, reserved, PROT_NONE, MAP_PRIVATE | MAP_ANON,
-1, 0)) != MAP_FAILED))
xflags = MAP_FIXED;
else
{
p = NULL;
reserved = total;
}
size_t reserved;
int xflags;
void *p = prepare_address_space (fd, total, &reserved, &xflags);
/* Map the header and all the administration data structures. */
p = mmap64 (p, total, PROT_READ | PROT_WRITE, MAP_SHARED | xflags, fd, 0);
@ -605,20 +606,9 @@ open_archive (struct locarhandle *ah, bool readonly)
ah->fd = fd;
ah->mmaped = st.st_size;
/* To prepare for enlargements of the mmaped area reserve some
address space. */
size_t reserved = RESERVE_MMAP_SIZE;
int xflags = 0;
void *p;
if (st.st_size < reserved
&& ((p = mmap64 (NULL, reserved, PROT_NONE, MAP_PRIVATE | MAP_ANON,
-1, 0)) != MAP_FAILED))
xflags = MAP_FIXED;
else
{
p = NULL;
reserved = st.st_size;
}
size_t reserved;
int xflags;
void *p = prepare_address_space (fd, st.st_size, &reserved, &xflags);
/* Map the entire file. We might need to compare the category data
in the file with the newly added data. */