[PATCH] f_count may wrap around

make it atomic_long_t; while we are at it, get rid of useless checks in affs,
hfs and hpfs - ->open() always has it equal to 1, ->release() - to 0.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

11 files changed, 27 insertions, 39 deletions

diff --git a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c
index 739b3ab7bccc..ddccc074a76a 100644
--- a/drivers/net/ppp_generic.c
+++ b/drivers/net/ppp_generic.c
@@ -581,12 +581,12 @@ static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                         if (file == ppp->owner)
                                 ppp_shutdown_interface(ppp);
                 }
-                if (atomic_read(&file->f_count) <= 2) {
+                if (atomic_long_read(&file->f_count) <= 2) {
                         ppp_release(NULL, file);
                         err = 0;
                 } else
-                        printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%d\n",
-                               atomic_read(&file->f_count));
+                        printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%ld\n",
+                               atomic_long_read(&file->f_count));
                 unlock_kernel();
                 return err;
         }
diff --git a/fs/affs/file.c b/fs/affs/file.c
index 6eac7bdeec94..1377b1240b6e 100644
--- a/fs/affs/file.c
+++ b/fs/affs/file.c
@@ -46,8 +46,6 @@ const struct inode_operations affs_file_inode_operations = {
 static int
 affs_file_open(struct inode *inode, struct file *filp)
 {
-        if (atomic_read(&filp->f_count) != 1)
-                return 0;
         pr_debug("AFFS: open(%lu,%d)\n",
                  inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
         atomic_inc(&AFFS_I(inode)->i_opencnt);
@@ -57,8 +55,6 @@ affs_file_open(struct inode *inode, struct file *filp)
 static int
 affs_file_release(struct inode *inode, struct file *filp)
 {
-        if (atomic_read(&filp->f_count) != 0)
-                return 0;
         pr_debug("AFFS: release(%lu, %d)\n",
                  inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
 
diff --git a/fs/aio.c b/fs/aio.c
index 0051fd94b44e..f658441d5666 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -512,8 +512,8 @@ static void aio_fput_routine(struct work_struct *data)
  */
 static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
 {
-        dprintk(KERN_DEBUG "aio_put(%p): f_count=%d\n",
-                req, atomic_read(&req->ki_filp->f_count));
+        dprintk(KERN_DEBUG "aio_put(%p): f_count=%ld\n",
+                req, atomic_long_read(&req->ki_filp->f_count));
 
         assert_spin_locked(&ctx->ctx_lock);
 
@@ -528,7 +528,7 @@ static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
         /* Must be done under the lock to serialise against cancellation.
          * Call this aio_fput as it duplicates fput via the fput_work.
          */
-        if (unlikely(atomic_dec_and_test(&req->ki_filp->f_count))) {
+        if (unlikely(atomic_long_dec_and_test(&req->ki_filp->f_count))) {
                 get_ioctx(ctx);
                 spin_lock(&fput_lock);
                 list_add(&req->ki_list, &fput_head);
diff --git a/fs/file_table.c b/fs/file_table.c
index 83084225b4c3..f45a4493f9e7 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -120,7 +120,7 @@ struct file *get_empty_filp(void)
 
         tsk = current;
         INIT_LIST_HEAD(&f->f_u.fu_list);
-        atomic_set(&f->f_count, 1);
+        atomic_long_set(&f->f_count, 1);
         rwlock_init(&f->f_owner.lock);
         f->f_uid = tsk->fsuid;
         f->f_gid = tsk->fsgid;
@@ -219,7 +219,7 @@ EXPORT_SYMBOL(init_file);
 
 void fput(struct file *file)
 {
-        if (atomic_dec_and_test(&file->f_count))
+        if (atomic_long_dec_and_test(&file->f_count))
                 __fput(file);
 }
 
@@ -294,7 +294,7 @@ struct file *fget(unsigned int fd)
         rcu_read_lock();
         file = fcheck_files(files, fd);
         if (file) {
-                if (!atomic_inc_not_zero(&file->f_count)) {
+                if (!atomic_long_inc_not_zero(&file->f_count)) {
                         /* File object ref couldn't be taken */
                         rcu_read_unlock();
                         return NULL;
@@ -326,7 +326,7 @@ struct file *fget_light(unsigned int fd, int *fput_needed)
                 rcu_read_lock();
                 file = fcheck_files(files, fd);
                 if (file) {
-                        if (atomic_inc_not_zero(&file->f_count))
+                        if (atomic_long_inc_not_zero(&file->f_count))
                                 *fput_needed = 1;
                         else
                                 /* Didn't get the reference, someone's freed */
@@ -341,7 +341,7 @@ struct file *fget_light(unsigned int fd, int *fput_needed)
 
 void put_filp(struct file *file)
 {
-        if (atomic_dec_and_test(&file->f_count)) {
+        if (atomic_long_dec_and_test(&file->f_count)) {
                 security_file_free(file);
                 file_kill(file);
                 file_free(file);
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index aa73f3fd5dd9..7e19835efa2e 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -522,8 +522,6 @@ static int hfs_file_open(struct inode *inode, struct file *file)
 {
         if (HFS_IS_RSRC(inode))
                 inode = HFS_I(inode)->rsrc_inode;
-        if (atomic_read(&file->f_count) != 1)
-                return 0;
         atomic_inc(&HFS_I(inode)->opencnt);
         return 0;
 }
@@ -534,8 +532,6 @@ static int hfs_file_release(struct inode *inode, struct file *file)
 
         if (HFS_IS_RSRC(inode))
                 inode = HFS_I(inode)->rsrc_inode;
-        if (atomic_read(&file->f_count) != 0)
-                return 0;
         if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
                 mutex_lock(&inode->i_mutex);
                 hfs_file_truncate(inode);
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index d4014e3044d2..b085d64a2b67 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -254,8 +254,6 @@ static int hfsplus_file_open(struct inode *inode, struct file *file)
 {
         if (HFSPLUS_IS_RSRC(inode))
                 inode = HFSPLUS_I(inode).rsrc_inode;
-        if (atomic_read(&file->f_count) != 1)
-                return 0;
         atomic_inc(&HFSPLUS_I(inode).opencnt);
         return 0;
 }
@@ -266,8 +264,6 @@ static int hfsplus_file_release(struct inode *inode, struct file *file)
 
         if (HFSPLUS_IS_RSRC(inode))
                 inode = HFSPLUS_I(inode).rsrc_inode;
-        if (atomic_read(&file->f_count) != 0)
-                return 0;
         if (atomic_dec_and_test(&HFSPLUS_I(inode).opencnt)) {
                 mutex_lock(&inode->i_mutex);
                 hfsplus_file_truncate(inode);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9d2de4cadabd..7676fa1c20ae 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -795,7 +795,7 @@ struct file {
 #define f_dentry        f_path.dentry
 #define f_vfsmnt        f_path.mnt
         const struct file_operations    *f_op;
-        atomic_t                f_count;
+        atomic_long_t           f_count;
         unsigned int            f_flags;
         mode_t                  f_mode;
         loff_t                  f_pos;
@@ -824,8 +824,8 @@ extern spinlock_t files_lock;
 #define file_list_lock() spin_lock(&files_lock);
 #define file_list_unlock() spin_unlock(&files_lock);
 
-#define get_file(x)     atomic_inc(&(x)->f_count)
-#define file_count(x)   atomic_read(&(x)->f_count)
+#define get_file(x)     atomic_long_inc(&(x)->f_count)
+#define file_count(x)   atomic_long_read(&(x)->f_count)
 
 #ifdef CONFIG_DEBUG_WRITECOUNT
 static inline void file_take_write(struct file *f)
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 2dfa96b0575e..7dd29b7e461d 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -51,7 +51,7 @@ struct unix_sock {
         struct sock             *peer;
         struct sock             *other;
         struct list_head        link;
-        atomic_t                inflight;
+        atomic_long_t           inflight;
         spinlock_t              lock;
         unsigned int            gc_candidate : 1;
         wait_queue_head_t       peer_wait;
diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index 04faa835be17..6b517b9dac5b 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -162,7 +162,7 @@ static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
         qdisc_destroy(flow->q);
         tcf_destroy_chain(&flow->filter_list);
         if (flow->sock) {
-                pr_debug("atm_tc_put: f_count %d\n",
+                pr_debug("atm_tc_put: f_count %ld\n",
                         file_count(flow->sock->file));
                 flow->vcc->pop = flow->old_pop;
                 sockfd_put(flow->sock);
@@ -259,7 +259,7 @@ static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
         sock = sockfd_lookup(fd, &error);
         if (!sock)
                 return error;   /* f_count++ */
-        pr_debug("atm_tc_change: f_count %d\n", file_count(sock->file));
+        pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
                 error = -EPROTOTYPE;
                 goto err_out;
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 70ceb1604ad8..6e7fec74bdb3 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -603,7 +603,7 @@ static struct sock * unix_create1(struct net *net, struct socket *sock)
         u->dentry = NULL;
         u->mnt    = NULL;
         spin_lock_init(&u->lock);
-        atomic_set(&u->inflight, 0);
+        atomic_long_set(&u->inflight, 0);
         INIT_LIST_HEAD(&u->link);
         mutex_init(&u->readlock); /* single task reading lock */
         init_waitqueue_head(&u->peer_wait);
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index ebdff3d877a1..2a27b84f740b 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -127,7 +127,7 @@ void unix_inflight(struct file *fp)
         if(s) {
                 struct unix_sock *u = unix_sk(s);
                 spin_lock(&unix_gc_lock);
-                if (atomic_inc_return(&u->inflight) == 1) {
+                if (atomic_long_inc_return(&u->inflight) == 1) {
                         BUG_ON(!list_empty(&u->link));
                         list_add_tail(&u->link, &gc_inflight_list);
                 } else {
@@ -145,7 +145,7 @@ void unix_notinflight(struct file *fp)
                 struct unix_sock *u = unix_sk(s);
                 spin_lock(&unix_gc_lock);
                 BUG_ON(list_empty(&u->link));
-                if (atomic_dec_and_test(&u->inflight))
+                if (atomic_long_dec_and_test(&u->inflight))
                         list_del_init(&u->link);
                 unix_tot_inflight--;
                 spin_unlock(&unix_gc_lock);
@@ -237,17 +237,17 @@ static void scan_children(struct sock *x, void (*func)(struct unix_sock *),
 
 static void dec_inflight(struct unix_sock *usk)
 {
-        atomic_dec(&usk->inflight);
+        atomic_long_dec(&usk->inflight);
 }
 
 static void inc_inflight(struct unix_sock *usk)
 {
-        atomic_inc(&usk->inflight);
+        atomic_long_inc(&usk->inflight);
 }
 
 static void inc_inflight_move_tail(struct unix_sock *u)
 {
-        atomic_inc(&u->inflight);
+        atomic_long_inc(&u->inflight);
         /*
          * If this is still a candidate, move it to the end of the
          * list, so that it's checked even if it was already passed
@@ -288,11 +288,11 @@ void unix_gc(void)
          * before the detach without atomicity guarantees.
          */
         list_for_each_entry_safe(u, next, &gc_inflight_list, link) {
-                int total_refs;
-                int inflight_refs;
+                long total_refs;
+                long inflight_refs;
 
                 total_refs = file_count(u->sk.sk_socket->file);
-                inflight_refs = atomic_read(&u->inflight);
+                inflight_refs = atomic_long_read(&u->inflight);
 
                 BUG_ON(inflight_refs < 1);
                 BUG_ON(total_refs < inflight_refs);
@@ -324,7 +324,7 @@ void unix_gc(void)
                 /* Move cursor to after the current position. */
                 list_move(&cursor, &u->link);
 
-                if (atomic_read(&u->inflight) > 0) {
+                if (atomic_long_read(&u->inflight) > 0) {
                         list_move_tail(&u->link, &gc_inflight_list);
                         u->gc_candidate = 0;
                         scan_children(&u->sk, inc_inflight_move_tail, NULL);