[PATCH] files: break up files struct
In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically. Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure. This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct. It also changes all
the users to refer to the file table using files_fdtable() macro. Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 167fd89f..2b03418 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -974,6 +974,7 @@
size_t size;
long timeout;
int ret = -EINVAL;
+ struct fdtable *fdt;
timeout = MAX_SCHEDULE_TIMEOUT;
if (tvp) {
@@ -995,7 +996,8 @@
}
}
- if (n < 0 || n > current->files->max_fdset)
+ fdt = files_fdtable(current->files);
+ if (n < 0 || n > fdt->max_fdset)
goto out_nofds;
/*
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index f1201ac..4ad97b3 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -38,6 +38,7 @@
#include <linux/pagemap.h>
#include <linux/mount.h>
#include <linux/bitops.h>
+#include <linux/rcupdate.h>
#include <asm/errno.h>
#include <asm/intrinsics.h>
@@ -2217,15 +2218,17 @@
pfm_free_fd(int fd, struct file *file)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt = files_fdtable(files);
/*
* there ie no fd_uninstall(), so we do it here
*/
spin_lock(&files->file_lock);
- files->fd[fd] = NULL;
+ rcu_assign_pointer(fdt->fd[fd], NULL);
spin_unlock(&files->file_lock);
- if (file) put_filp(file);
+ if (file)
+ put_filp(file);
put_unused_fd(fd);
}
diff --git a/arch/sparc64/solaris/ioctl.c b/arch/sparc64/solaris/ioctl.c
index cac0a1c..3747664 100644
--- a/arch/sparc64/solaris/ioctl.c
+++ b/arch/sparc64/solaris/ioctl.c
@@ -293,11 +293,13 @@
static inline int solaris_sockmod(unsigned int fd, unsigned int cmd, u32 arg)
{
struct inode *ino;
+ struct fdtable *fdt;
/* I wonder which of these tests are superfluous... --patrik */
spin_lock(¤t->files->file_lock);
- if (! current->files->fd[fd] ||
- ! current->files->fd[fd]->f_dentry ||
- ! (ino = current->files->fd[fd]->f_dentry->d_inode) ||
+ fdt = files_fdtable(current->files);
+ if (! fdt->fd[fd] ||
+ ! fdt->fd[fd]->f_dentry ||
+ ! (ino = fdt->fd[fd]->f_dentry->d_inode) ||
! S_ISSOCK(ino->i_mode)) {
spin_unlock(¤t->files->file_lock);
return TBADF;
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 6a56ae4..0bfc7af 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -2454,6 +2454,7 @@
int i;
struct file *filp;
struct tty_ldisc *disc;
+ struct fdtable *fdt;
if (!tty)
return;
@@ -2480,7 +2481,8 @@
task_lock(p);
if (p->files) {
spin_lock(&p->files->file_lock);
- for (i=0; i < p->files->max_fds; i++) {
+ fdt = files_fdtable(p->files);
+ for (i=0; i < fdt->max_fds; i++) {
filp = fcheck_files(p->files, i);
if (!filp)
continue;
diff --git a/fs/exec.c b/fs/exec.c
index 222ab1c..14dd039 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -798,6 +798,7 @@
static inline void flush_old_files(struct files_struct * files)
{
long j = -1;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
for (;;) {
@@ -805,12 +806,13 @@
j++;
i = j * __NFDBITS;
- if (i >= files->max_fds || i >= files->max_fdset)
+ fdt = files_fdtable(files);
+ if (i >= fdt->max_fds || i >= fdt->max_fdset)
break;
- set = files->close_on_exec->fds_bits[j];
+ set = fdt->close_on_exec->fds_bits[j];
if (!set)
continue;
- files->close_on_exec->fds_bits[j] = 0;
+ fdt->close_on_exec->fds_bits[j] = 0;
spin_unlock(&files->file_lock);
for ( ; set ; i++,set >>= 1) {
if (set & 1) {
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 6fbc9d8..bfecc62 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -24,20 +24,24 @@
void fastcall set_close_on_exec(unsigned int fd, int flag)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
+ fdt = files_fdtable(files);
if (flag)
- FD_SET(fd, files->close_on_exec);
+ FD_SET(fd, fdt->close_on_exec);
else
- FD_CLR(fd, files->close_on_exec);
+ FD_CLR(fd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
}
static inline int get_close_on_exec(unsigned int fd)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt;
int res;
spin_lock(&files->file_lock);
- res = FD_ISSET(fd, files->close_on_exec);
+ fdt = files_fdtable(files);
+ res = FD_ISSET(fd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
return res;
}
@@ -54,24 +58,26 @@
unsigned int newfd;
unsigned int start;
int error;
+ struct fdtable *fdt;
error = -EINVAL;
if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
goto out;
+ fdt = files_fdtable(files);
repeat:
/*
* Someone might have closed fd's in the range
- * orig_start..files->next_fd
+ * orig_start..fdt->next_fd
*/
start = orig_start;
- if (start < files->next_fd)
- start = files->next_fd;
+ if (start < fdt->next_fd)
+ start = fdt->next_fd;
newfd = start;
- if (start < files->max_fdset) {
- newfd = find_next_zero_bit(files->open_fds->fds_bits,
- files->max_fdset, start);
+ if (start < fdt->max_fdset) {
+ newfd = find_next_zero_bit(fdt->open_fds->fds_bits,
+ fdt->max_fdset, start);
}
error = -EMFILE;
@@ -89,8 +95,8 @@
if (error)
goto repeat;
- if (start <= files->next_fd)
- files->next_fd = newfd + 1;
+ if (start <= fdt->next_fd)
+ fdt->next_fd = newfd + 1;
error = newfd;
@@ -101,13 +107,16 @@
static int dupfd(struct file *file, unsigned int start)
{
struct files_struct * files = current->files;
+ struct fdtable *fdt;
int fd;
spin_lock(&files->file_lock);
fd = locate_fd(files, file, start);
if (fd >= 0) {
- FD_SET(fd, files->open_fds);
- FD_CLR(fd, files->close_on_exec);
+ /* locate_fd() may have expanded fdtable, load the ptr */
+ fdt = files_fdtable(files);
+ FD_SET(fd, fdt->open_fds);
+ FD_CLR(fd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
fd_install(fd, file);
} else {
@@ -123,6 +132,7 @@
int err = -EBADF;
struct file * file, *tofree;
struct files_struct * files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
if (!(file = fcheck(oldfd)))
@@ -148,13 +158,14 @@
/* Yes. It's a race. In user space. Nothing sane to do */
err = -EBUSY;
- tofree = files->fd[newfd];
- if (!tofree && FD_ISSET(newfd, files->open_fds))
+ fdt = files_fdtable(files);
+ tofree = fdt->fd[newfd];
+ if (!tofree && FD_ISSET(newfd, fdt->open_fds))
goto out_fput;
- files->fd[newfd] = file;
- FD_SET(newfd, files->open_fds);
- FD_CLR(newfd, files->close_on_exec);
+ fdt->fd[newfd] = file;
+ FD_SET(newfd, fdt->open_fds);
+ FD_CLR(newfd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
if (tofree)
diff --git a/fs/file.c b/fs/file.c
index 92b5f25..f5926ce 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -59,13 +59,15 @@
{
struct file **new_fds;
int error, nfds;
+ struct fdtable *fdt;
error = -EMFILE;
- if (files->max_fds >= NR_OPEN || nr >= NR_OPEN)
+ fdt = files_fdtable(files);
+ if (fdt->max_fds >= NR_OPEN || nr >= NR_OPEN)
goto out;
- nfds = files->max_fds;
+ nfds = fdt->max_fds;
spin_unlock(&files->file_lock);
/*
@@ -95,13 +97,14 @@
goto out;
/* Copy the existing array and install the new pointer */
+ fdt = files_fdtable(files);
- if (nfds > files->max_fds) {
+ if (nfds > fdt->max_fds) {
struct file **old_fds;
int i;
- old_fds = xchg(&files->fd, new_fds);
- i = xchg(&files->max_fds, nfds);
+ old_fds = xchg(&fdt->fd, new_fds);
+ i = xchg(&fdt->max_fds, nfds);
/* Don't copy/clear the array if we are creating a new
fd array for fork() */
@@ -164,12 +167,14 @@
{
fd_set *new_openset = NULL, *new_execset = NULL;
int error, nfds = 0;
+ struct fdtable *fdt;
error = -EMFILE;
- if (files->max_fdset >= NR_OPEN || nr >= NR_OPEN)
+ fdt = files_fdtable(files);
+ if (fdt->max_fdset >= NR_OPEN || nr >= NR_OPEN)
goto out;
- nfds = files->max_fdset;
+ nfds = fdt->max_fdset;
spin_unlock(&files->file_lock);
/* Expand to the max in easy steps */
@@ -193,24 +198,25 @@
error = 0;
/* Copy the existing tables and install the new pointers */
- if (nfds > files->max_fdset) {
- int i = files->max_fdset / (sizeof(unsigned long) * 8);
- int count = (nfds - files->max_fdset) / 8;
+ fdt = files_fdtable(files);
+ if (nfds > fdt->max_fdset) {
+ int i = fdt->max_fdset / (sizeof(unsigned long) * 8);
+ int count = (nfds - fdt->max_fdset) / 8;
/*
* Don't copy the entire array if the current fdset is
* not yet initialised.
*/
if (i) {
- memcpy (new_openset, files->open_fds, files->max_fdset/8);
- memcpy (new_execset, files->close_on_exec, files->max_fdset/8);
+ memcpy (new_openset, fdt->open_fds, fdt->max_fdset/8);
+ memcpy (new_execset, fdt->close_on_exec, fdt->max_fdset/8);
memset (&new_openset->fds_bits[i], 0, count);
memset (&new_execset->fds_bits[i], 0, count);
}
- nfds = xchg(&files->max_fdset, nfds);
- new_openset = xchg(&files->open_fds, new_openset);
- new_execset = xchg(&files->close_on_exec, new_execset);
+ nfds = xchg(&fdt->max_fdset, nfds);
+ new_openset = xchg(&fdt->open_fds, new_openset);
+ new_execset = xchg(&fdt->close_on_exec, new_execset);
spin_unlock(&files->file_lock);
free_fdset (new_openset, nfds);
free_fdset (new_execset, nfds);
@@ -237,13 +243,15 @@
int expand_files(struct files_struct *files, int nr)
{
int err, expand = 0;
+ struct fdtable *fdt;
- if (nr >= files->max_fdset) {
+ fdt = files_fdtable(files);
+ if (nr >= fdt->max_fdset) {
expand = 1;
if ((err = expand_fdset(files, nr)))
goto out;
}
- if (nr >= files->max_fds) {
+ if (nr >= fdt->max_fds) {
expand = 1;
if ((err = expand_fd_array(files, nr)))
goto out;
diff --git a/fs/locks.c b/fs/locks.c
index 11956b6..c2c09b4 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -2198,21 +2198,23 @@
{
struct files_struct *files = current->files;
int i, j;
+ struct fdtable *fdt;
if (from == files)
return;
lock_kernel();
j = 0;
+ fdt = files_fdtable(files);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
- if (i >= files->max_fdset || i >= files->max_fds)
+ if (i >= fdt->max_fdset || i >= fdt->max_fds)
break;
- set = files->open_fds->fds_bits[j++];
+ set = fdt->open_fds->fds_bits[j++];
while (set) {
if (set & 1) {
- struct file *file = files->fd[i];
+ struct file *file = fdt->fd[i];
if (file)
__steal_locks(file, from);
}
diff --git a/fs/open.c b/fs/open.c
index 4ee2dcc..b654251 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -842,14 +842,16 @@
{
struct files_struct * files = current->files;
int fd, error;
+ struct fdtable *fdt;
error = -EMFILE;
spin_lock(&files->file_lock);
repeat:
- fd = find_next_zero_bit(files->open_fds->fds_bits,
- files->max_fdset,
- files->next_fd);
+ fdt = files_fdtable(files);
+ fd = find_next_zero_bit(fdt->open_fds->fds_bits,
+ fdt->max_fdset,
+ fdt->next_fd);
/*
* N.B. For clone tasks sharing a files structure, this test
@@ -872,14 +874,14 @@
goto repeat;
}
- FD_SET(fd, files->open_fds);
- FD_CLR(fd, files->close_on_exec);
- files->next_fd = fd + 1;
+ FD_SET(fd, fdt->open_fds);
+ FD_CLR(fd, fdt->close_on_exec);
+ fdt->next_fd = fd + 1;
#if 1
/* Sanity check */
- if (files->fd[fd] != NULL) {
+ if (fdt->fd[fd] != NULL) {
printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd);
- files->fd[fd] = NULL;
+ fdt->fd[fd] = NULL;
}
#endif
error = fd;
@@ -893,9 +895,10 @@
static inline void __put_unused_fd(struct files_struct *files, unsigned int fd)
{
- __FD_CLR(fd, files->open_fds);
- if (fd < files->next_fd)
- files->next_fd = fd;
+ struct fdtable *fdt = files_fdtable(files);
+ __FD_CLR(fd, fdt->open_fds);
+ if (fd < fdt->next_fd)
+ fdt->next_fd = fd;
}
void fastcall put_unused_fd(unsigned int fd)
@@ -924,10 +927,12 @@
void fastcall fd_install(unsigned int fd, struct file * file)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
- if (unlikely(files->fd[fd] != NULL))
+ fdt = files_fdtable(files);
+ if (unlikely(fdt->fd[fd] != NULL))
BUG();
- files->fd[fd] = file;
+ fdt->fd[fd] = file;
spin_unlock(&files->file_lock);
}
@@ -1010,15 +1015,17 @@
{
struct file * filp;
struct files_struct *files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
- if (fd >= files->max_fds)
+ fdt = files_fdtable(files);
+ if (fd >= fdt->max_fds)
goto out_unlock;
- filp = files->fd[fd];
+ filp = fdt->fd[fd];
if (!filp)
goto out_unlock;
- files->fd[fd] = NULL;
- FD_CLR(fd, files->close_on_exec);
+ fdt->fd[fd] = NULL;
+ FD_CLR(fd, fdt->close_on_exec);
__put_unused_fd(files, fd);
spin_unlock(&files->file_lock);
return filp_close(filp, files);
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 37668fe..d88d518 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -159,6 +159,7 @@
{
struct group_info *group_info;
int g;
+ struct fdtable *fdt = NULL;
read_lock(&tasklist_lock);
buffer += sprintf(buffer,
@@ -179,10 +180,12 @@
p->gid, p->egid, p->sgid, p->fsgid);
read_unlock(&tasklist_lock);
task_lock(p);
+ if (p->files)
+ fdt = files_fdtable(p->files);
buffer += sprintf(buffer,
"FDSize:\t%d\n"
"Groups:\t",
- p->files ? p->files->max_fds : 0);
+ fdt ? fdt->max_fds : 0);
group_info = p->group_info;
get_group_info(group_info);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 84751f3..d0087a0 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1039,6 +1039,7 @@
int retval;
char buf[NUMBUF];
struct files_struct * files;
+ struct fdtable *fdt;
retval = -ENOENT;
if (!pid_alive(p))
@@ -1062,8 +1063,9 @@
if (!files)
goto out;
spin_lock(&files->file_lock);
+ fdt = files_fdtable(files);
for (fd = filp->f_pos-2;
- fd < files->max_fds;
+ fd < fdt->max_fds;
fd++, filp->f_pos++) {
unsigned int i,j;
diff --git a/fs/select.c b/fs/select.c
index b80e7eb..2e56325 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -132,11 +132,13 @@
unsigned long *open_fds;
unsigned long set;
int max;
+ struct fdtable *fdt;
/* handle last in-complete long-word first */
set = ~(~0UL << (n & (__NFDBITS-1)));
n /= __NFDBITS;
- open_fds = current->files->open_fds->fds_bits+n;
+ fdt = files_fdtable(current->files);
+ open_fds = fdt->open_fds->fds_bits+n;
max = 0;
if (set) {
set &= BITS(fds, n);
@@ -299,6 +301,7 @@
char *bits;
long timeout;
int ret, size, max_fdset;
+ struct fdtable *fdt;
timeout = MAX_SCHEDULE_TIMEOUT;
if (tvp) {
@@ -326,7 +329,8 @@
goto out_nofds;
/* max_fdset can increase, so grab it once to avoid race */
- max_fdset = current->files->max_fdset;
+ fdt = files_fdtable(current->files);
+ max_fdset = fdt->max_fdset;
if (n > max_fdset)
n = max_fdset;
@@ -464,9 +468,11 @@
unsigned int i;
struct poll_list *head;
struct poll_list *walk;
+ struct fdtable *fdt;
/* Do a sanity check on nfds ... */
- if (nfds > current->files->max_fdset && nfds > OPEN_MAX)
+ fdt = files_fdtable(current->files);
+ if (nfds > fdt->max_fdset && nfds > OPEN_MAX)
return -EINVAL;
if (timeout) {
diff --git a/include/linux/file.h b/include/linux/file.h
index 5206beb..db37223 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -16,23 +16,29 @@
*/
#define NR_OPEN_DEFAULT BITS_PER_LONG
+struct fdtable {
+ unsigned int max_fds;
+ int max_fdset;
+ int next_fd;
+ struct file ** fd; /* current fd array */
+ fd_set *close_on_exec;
+ fd_set *open_fds;
+};
+
/*
* Open file table structure
*/
struct files_struct {
atomic_t count;
spinlock_t file_lock; /* Protects all the below members. Nests inside tsk->alloc_lock */
- int max_fds;
- int max_fdset;
- int next_fd;
- struct file ** fd; /* current fd array */
- fd_set *close_on_exec;
- fd_set *open_fds;
+ struct fdtable fdtab;
fd_set close_on_exec_init;
fd_set open_fds_init;
struct file * fd_array[NR_OPEN_DEFAULT];
};
+#define files_fdtable(files) (&(files)->fdtab)
+
extern void FASTCALL(__fput(struct file *));
extern void FASTCALL(fput(struct file *));
@@ -63,9 +69,10 @@
static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd)
{
struct file * file = NULL;
+ struct fdtable *fdt = files_fdtable(files);
- if (fd < files->max_fds)
- file = files->fd[fd];
+ if (fd < fdt->max_fds)
+ file = fdt->fd[fd];
return file;
}
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index c727c195..94aefa5 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -3,16 +3,21 @@
#include <linux/file.h>
-#define INIT_FILES \
-{ \
- .count = ATOMIC_INIT(1), \
- .file_lock = SPIN_LOCK_UNLOCKED, \
+#define INIT_FDTABLE \
+{ \
.max_fds = NR_OPEN_DEFAULT, \
.max_fdset = __FD_SETSIZE, \
.next_fd = 0, \
.fd = &init_files.fd_array[0], \
.close_on_exec = &init_files.close_on_exec_init, \
.open_fds = &init_files.open_fds_init, \
+}
+
+#define INIT_FILES \
+{ \
+ .count = ATOMIC_INIT(1), \
+ .file_lock = SPIN_LOCK_UNLOCKED, \
+ .fdtab = INIT_FDTABLE, \
.close_on_exec_init = { { 0, } }, \
.open_fds_init = { { 0, } }, \
.fd_array = { NULL, } \
diff --git a/kernel/exit.c b/kernel/exit.c
index 5b0fb9f..83beb1e 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -368,17 +368,19 @@
static inline void close_files(struct files_struct * files)
{
int i, j;
+ struct fdtable *fdt;
j = 0;
+ fdt = files_fdtable(files);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
- if (i >= files->max_fdset || i >= files->max_fds)
+ if (i >= fdt->max_fdset || i >= fdt->max_fds)
break;
- set = files->open_fds->fds_bits[j++];
+ set = fdt->open_fds->fds_bits[j++];
while (set) {
if (set & 1) {
- struct file * file = xchg(&files->fd[i], NULL);
+ struct file * file = xchg(&fdt->fd[i], NULL);
if (file)
filp_close(file, files);
}
@@ -403,16 +405,19 @@
void fastcall put_files_struct(struct files_struct *files)
{
+ struct fdtable *fdt;
+
if (atomic_dec_and_test(&files->count)) {
close_files(files);
/*
* Free the fd and fdset arrays if we expanded them.
*/
- if (files->fd != &files->fd_array[0])
- free_fd_array(files->fd, files->max_fds);
- if (files->max_fdset > __FD_SETSIZE) {
- free_fdset(files->open_fds, files->max_fdset);
- free_fdset(files->close_on_exec, files->max_fdset);
+ fdt = files_fdtable(files);
+ if (fdt->fd != &files->fd_array[0])
+ free_fd_array(fdt->fd, fdt->max_fds);
+ if (fdt->max_fdset > __FD_SETSIZE) {
+ free_fdset(fdt->open_fds, fdt->max_fdset);
+ free_fdset(fdt->close_on_exec, fdt->max_fdset);
}
kmem_cache_free(files_cachep, files);
}
diff --git a/kernel/fork.c b/kernel/fork.c
index b258020..ecc694d 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -568,21 +568,47 @@
static int count_open_files(struct files_struct *files, int size)
{
int i;
+ struct fdtable *fdt;
/* Find the last open fd */
+ fdt = files_fdtable(files);
for (i = size/(8*sizeof(long)); i > 0; ) {
- if (files->open_fds->fds_bits[--i])
+ if (fdt->open_fds->fds_bits[--i])
break;
}
i = (i+1) * 8 * sizeof(long);
return i;
}
+static struct files_struct *alloc_files(void)
+{
+ struct files_struct *newf;
+ struct fdtable *fdt;
+
+ newf = kmem_cache_alloc(files_cachep, SLAB_KERNEL);
+ if (!newf)
+ goto out;
+
+ atomic_set(&newf->count, 1);
+
+ spin_lock_init(&newf->file_lock);
+ fdt = files_fdtable(newf);
+ fdt->next_fd = 0;
+ fdt->max_fds = NR_OPEN_DEFAULT;
+ fdt->max_fdset = __FD_SETSIZE;
+ fdt->close_on_exec = &newf->close_on_exec_init;
+ fdt->open_fds = &newf->open_fds_init;
+ fdt->fd = &newf->fd_array[0];
+out:
+ return newf;
+}
+
static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
{
struct files_struct *oldf, *newf;
struct file **old_fds, **new_fds;
int open_files, size, i, error = 0, expand;
+ struct fdtable *old_fdt, *new_fdt;
/*
* A background process may not have any files ...
@@ -603,35 +629,27 @@
*/
tsk->files = NULL;
error = -ENOMEM;
- newf = kmem_cache_alloc(files_cachep, SLAB_KERNEL);
- if (!newf)
+ newf = alloc_files();
+ if (!newf)
goto out;
- atomic_set(&newf->count, 1);
-
- spin_lock_init(&newf->file_lock);
- newf->next_fd = 0;
- newf->max_fds = NR_OPEN_DEFAULT;
- newf->max_fdset = __FD_SETSIZE;
- newf->close_on_exec = &newf->close_on_exec_init;
- newf->open_fds = &newf->open_fds_init;
- newf->fd = &newf->fd_array[0];
-
spin_lock(&oldf->file_lock);
-
- open_files = count_open_files(oldf, oldf->max_fdset);
+ old_fdt = files_fdtable(oldf);
+ new_fdt = files_fdtable(newf);
+ size = old_fdt->max_fdset;
+ open_files = count_open_files(oldf, old_fdt->max_fdset);
expand = 0;
/*
* Check whether we need to allocate a larger fd array or fd set.
* Note: we're not a clone task, so the open count won't change.
*/
- if (open_files > newf->max_fdset) {
- newf->max_fdset = 0;
+ if (open_files > new_fdt->max_fdset) {
+ new_fdt->max_fdset = 0;
expand = 1;
}
- if (open_files > newf->max_fds) {
- newf->max_fds = 0;
+ if (open_files > new_fdt->max_fds) {
+ new_fdt->max_fds = 0;
expand = 1;
}
@@ -646,11 +664,11 @@
spin_lock(&oldf->file_lock);
}
- old_fds = oldf->fd;
- new_fds = newf->fd;
+ old_fds = old_fdt->fd;
+ new_fds = new_fdt->fd;
- memcpy(newf->open_fds->fds_bits, oldf->open_fds->fds_bits, open_files/8);
- memcpy(newf->close_on_exec->fds_bits, oldf->close_on_exec->fds_bits, open_files/8);
+ memcpy(new_fdt->open_fds->fds_bits, old_fdt->open_fds->fds_bits, open_files/8);
+ memcpy(new_fdt->close_on_exec->fds_bits, old_fdt->close_on_exec->fds_bits, open_files/8);
for (i = open_files; i != 0; i--) {
struct file *f = *old_fds++;
@@ -663,24 +681,24 @@
* is partway through open(). So make sure that this
* fd is available to the new process.
*/
- FD_CLR(open_files - i, newf->open_fds);
+ FD_CLR(open_files - i, new_fdt->open_fds);
}
*new_fds++ = f;
}
spin_unlock(&oldf->file_lock);
/* compute the remainder to be cleared */
- size = (newf->max_fds - open_files) * sizeof(struct file *);
+ size = (new_fdt->max_fds - open_files) * sizeof(struct file *);
/* This is long word aligned thus could use a optimized version */
memset(new_fds, 0, size);
- if (newf->max_fdset > open_files) {
- int left = (newf->max_fdset-open_files)/8;
+ if (new_fdt->max_fdset > open_files) {
+ int left = (new_fdt->max_fdset-open_files)/8;
int start = open_files / (8 * sizeof(unsigned long));
- memset(&newf->open_fds->fds_bits[start], 0, left);
- memset(&newf->close_on_exec->fds_bits[start], 0, left);
+ memset(&new_fdt->open_fds->fds_bits[start], 0, left);
+ memset(&new_fdt->close_on_exec->fds_bits[start], 0, left);
}
tsk->files = newf;
@@ -689,9 +707,9 @@
return error;
out_release:
- free_fdset (newf->close_on_exec, newf->max_fdset);
- free_fdset (newf->open_fds, newf->max_fdset);
- free_fd_array(newf->fd, newf->max_fds);
+ free_fdset (new_fdt->close_on_exec, new_fdt->max_fdset);
+ free_fdset (new_fdt->open_fds, new_fdt->max_fdset);
+ free_fd_array(new_fdt->fd, new_fdt->max_fds);
kmem_cache_free(files_cachep, newf);
goto out;
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 3f0b533..acb5a49 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1594,6 +1594,7 @@
struct avc_audit_data ad;
struct file *file, *devnull = NULL;
struct tty_struct *tty = current->signal->tty;
+ struct fdtable *fdt;
long j = -1;
if (tty) {
@@ -1627,9 +1628,10 @@
j++;
i = j * __NFDBITS;
- if (i >= files->max_fds || i >= files->max_fdset)
+ fdt = files_fdtable(files);
+ if (i >= fdt->max_fds || i >= fdt->max_fdset)
break;
- set = files->open_fds->fds_bits[j];
+ set = fdt->open_fds->fds_bits[j];
if (!set)
continue;
spin_unlock(&files->file_lock);
