X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Ffcntl.c;h=13b97ae9ec3ecf69ee2449073e034351ed88c52c;hb=refs%2Fheads%2Fvserver;hp=65c30d64e6ab69a698c6d2d388aee36c8c290d08;hpb=6a77f38946aaee1cd85eeec6cf4229b204c15071;p=linux-2.6.git diff --git a/fs/fcntl.c b/fs/fcntl.c index 65c30d64e..13b97ae9e 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -9,12 +9,15 @@ #include #include #include +#include #include #include #include #include #include #include +#include +#include #include #include @@ -24,21 +27,25 @@ 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) +static 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); - spin_unlock(&files->file_lock); + rcu_read_lock(); + fdt = files_fdtable(files); + res = FD_ISSET(fd, fdt->close_on_exec); + rcu_read_unlock(); return res; } @@ -54,25 +61,26 @@ static int locate_fd(struct files_struct *files, 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; repeat: + fdt = files_fdtable(files); /* * 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; 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_fds) + newfd = find_next_zero_bit(fdt->open_fds->fds_bits, + fdt->max_fds, start); error = -EMFILE; if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) @@ -91,9 +99,14 @@ repeat: if (error) goto repeat; + /* + * We reacquired files_lock, so we are safe as long as + * we reacquire the fdtable pointer and use it while holding + * the lock, no one can free it during that time. + */ if (start <= files->next_fd) files->next_fd = newfd + 1; - + error = newfd; out: @@ -103,13 +116,16 @@ out: 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); vx_openfd_inc(fd); fd_install(fd, file); @@ -126,6 +142,7 @@ asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd) 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))) @@ -151,13 +168,14 @@ asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd) /* 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); + rcu_assign_pointer(fdt->fd[newfd], file); + FD_SET(newfd, fdt->open_fds); + FD_CLR(newfd, fdt->close_on_exec); spin_unlock(&files->file_lock); if (tofree) @@ -192,11 +210,14 @@ asmlinkage long sys_dup(unsigned int fildes) static int setfl(int fd, struct file * filp, unsigned long arg) { - struct inode * inode = filp->f_dentry->d_inode; + struct inode * inode = filp->f_path.dentry->d_inode; int error = 0; - /* O_APPEND cannot be cleared if the file is marked as append-only */ - if (!(arg & O_APPEND) && IS_APPEND(inode)) + /* + * O_APPEND cannot be cleared if the file is marked as append-only + * and the file is open for write. + */ + if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode)) return -EPERM; /* O_NOATIME can only be set by the owner or superuser */ @@ -235,19 +256,22 @@ static int setfl(int fd, struct file * filp, unsigned long arg) return error; } -static void f_modown(struct file *filp, unsigned long pid, +static void f_modown(struct file *filp, struct pid *pid, enum pid_type type, uid_t uid, uid_t euid, int force) { write_lock_irq(&filp->f_owner.lock); if (force || !filp->f_owner.pid) { - filp->f_owner.pid = pid; + put_pid(filp->f_owner.pid); + filp->f_owner.pid = get_pid(pid); + filp->f_owner.pid_type = type; filp->f_owner.uid = uid; filp->f_owner.euid = euid; } write_unlock_irq(&filp->f_owner.lock); } -int f_setown(struct file *filp, unsigned long arg, int force) +int __f_setown(struct file *filp, struct pid *pid, enum pid_type type, + int force) { int err; @@ -255,15 +279,44 @@ int f_setown(struct file *filp, unsigned long arg, int force) if (err) return err; - f_modown(filp, arg, current->uid, current->euid, force); + f_modown(filp, pid, type, current->uid, current->euid, force); return 0; } +EXPORT_SYMBOL(__f_setown); +int f_setown(struct file *filp, unsigned long arg, int force) +{ + enum pid_type type; + struct pid *pid; + int who = arg; + int result; + type = PIDTYPE_PID; + if (who < 0) { + type = PIDTYPE_PGID; + who = -who; + } + rcu_read_lock(); + pid = find_pid(who); + result = __f_setown(filp, pid, type, force); + rcu_read_unlock(); + return result; +} EXPORT_SYMBOL(f_setown); void f_delown(struct file *filp) { - f_modown(filp, 0, 0, 0, 1); + f_modown(filp, NULL, PIDTYPE_PID, 0, 0, 1); +} + +pid_t f_getown(struct file *filp) +{ + pid_t pid; + read_lock(&filp->f_owner.lock); + pid = pid_nr(filp->f_owner.pid); + if (filp->f_owner.pid_type == PIDTYPE_PGID) + pid = -pid; + read_unlock(&filp->f_owner.lock); + return pid; } static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, @@ -294,7 +347,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, break; case F_SETLK: case F_SETLKW: - err = fcntl_setlk(filp, cmd, (struct flock __user *) arg); + err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg); break; case F_GETOWN: /* @@ -304,7 +357,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, * current syscall conventions, the only way * to fix this will be in libc. */ - err = filp->f_owner.pid; + err = f_getown(filp); force_successful_syscall_return(); break; case F_SETOWN: @@ -315,7 +368,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, break; case F_SETSIG: /* arg == 0 restores default behaviour. */ - if (arg < 0 || arg > _NSIG) { + if (!valid_signal(arg)) { break; } err = 0; @@ -382,7 +435,8 @@ asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg break; case F_SETLK64: case F_SETLKW64: - err = fcntl_setlk64(filp, cmd, (struct flock64 __user *) arg); + err = fcntl_setlk64(fd, filp, cmd, + (struct flock64 __user *) arg); break; default: err = do_fcntl(fd, cmd, arg, filp); @@ -396,7 +450,7 @@ out: /* Table to convert sigio signal codes into poll band bitmaps */ -static long band_table[NSIGPOLL] = { +static const long band_table[NSIGPOLL] = { POLLIN | POLLRDNORM, /* POLL_IN */ POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */ POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */ @@ -437,42 +491,36 @@ static void send_sigio_to_task(struct task_struct *p, /* Make sure we are called with one of the POLL_* reasons, otherwise we could leak kernel stack into userspace. */ - if ((reason & __SI_MASK) != __SI_POLL) - BUG(); + BUG_ON((reason & __SI_MASK) != __SI_POLL); if (reason - POLL_IN >= NSIGPOLL) si.si_band = ~0L; else si.si_band = band_table[reason - POLL_IN]; si.si_fd = fd; - if (!send_sig_info(fown->signum, &si, p)) + if (!group_send_sig_info(fown->signum, &si, p)) break; /* fall-through: fall back on the old plain SIGIO signal */ case 0: - send_group_sig_info(SIGIO, SEND_SIG_PRIV, p); + group_send_sig_info(SIGIO, SEND_SIG_PRIV, p); } } void send_sigio(struct fown_struct *fown, int fd, int band) { struct task_struct *p; - int pid; + enum pid_type type; + struct pid *pid; read_lock(&fown->lock); + type = fown->pid_type; pid = fown->pid; if (!pid) goto out_unlock_fown; read_lock(&tasklist_lock); - if (pid > 0) { - p = find_task_by_real_pid(pid); - if (p) { - send_sigio_to_task(p, fown, fd, band); - } - } else { - do_each_task_pid(-pid, PIDTYPE_PGID, p) { - send_sigio_to_task(p, fown, fd, band); - } while_each_task_pid(-pid, PIDTYPE_PGID, p); - } + do_each_pid_task(pid, type, p) { + send_sigio_to_task(p, fown, fd, band); + } while_each_pid_task(pid, type, p); read_unlock(&tasklist_lock); out_unlock_fown: read_unlock(&fown->lock); @@ -482,15 +530,18 @@ static void send_sigurg_to_task(struct task_struct *p, struct fown_struct *fown) { if (sigio_perm(p, fown, SIGURG)) - send_group_sig_info(SIGURG, SEND_SIG_PRIV, p); + group_send_sig_info(SIGURG, SEND_SIG_PRIV, p); } int send_sigurg(struct fown_struct *fown) { struct task_struct *p; - int pid, ret = 0; + enum pid_type type; + struct pid *pid; + int ret = 0; read_lock(&fown->lock); + type = fown->pid_type; pid = fown->pid; if (!pid) goto out_unlock_fown; @@ -498,24 +549,19 @@ int send_sigurg(struct fown_struct *fown) ret = 1; read_lock(&tasklist_lock); - if (pid > 0) { - p = find_task_by_real_pid(pid); - if (p) { - send_sigurg_to_task(p, fown); - } - } else { - do_each_task_pid(-pid, PIDTYPE_PGID, p) { - send_sigurg_to_task(p, fown); - } while_each_task_pid(-pid, PIDTYPE_PGID, p); - } + do_each_pid_task(pid, type, p) { + send_sigurg_to_task(p, fown); + } while_each_pid_task(pid, type, p); read_unlock(&tasklist_lock); out_unlock_fown: read_unlock(&fown->lock); return ret; } +EXPORT_SYMBOL(send_sigurg); + static DEFINE_RWLOCK(fasync_lock); -static kmem_cache_t *fasync_cache; +static struct kmem_cache *fasync_cache __read_mostly; /* * fasync_helper() is used by some character device drivers (mainly mice) @@ -529,7 +575,7 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap int result = 0; if (on) { - new = kmem_cache_alloc(fasync_cache, SLAB_KERNEL); + new = kmem_cache_alloc(fasync_cache, GFP_KERNEL); if (!new) return -ENOMEM; }