Date: Tue, 11 Nov 2008 14:55:59 +0000 (UTC) From: Ed Schouten <ed@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r184849 - in head: lib/libc/sys sys/amd64/linux32 sys/i386/linux sys/kern sys/sys Message-ID: <200811111455.mABEtxRH004631@svn.freebsd.org>
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Author: ed Date: Tue Nov 11 14:55:59 2008 New Revision: 184849 URL: http://svn.freebsd.org/changeset/base/184849 Log: Several cleanups related to pipe(2). - Use `fildes[2]' instead of `*fildes' to make more clear that pipe(2) fills an array with two descriptors. - Remove EFAULT from the manual page. Because of the current calling convention, pipe(2) raises a segmentation fault when an invalid address is passed. - Introduce kern_pipe() to make it easier for binary emulations to implement pipe(2). - Make Linux binary emulation use kern_pipe(), which means we don't have to recover td_retval after calling the FreeBSD system call. Approved by: rdivacky Discussed on: arch Modified: head/lib/libc/sys/pipe.2 head/sys/amd64/linux32/linux32_machdep.c head/sys/i386/linux/linux_machdep.c head/sys/kern/sys_pipe.c head/sys/sys/syscallsubr.h Modified: head/lib/libc/sys/pipe.2 ============================================================================== --- head/lib/libc/sys/pipe.2 Tue Nov 11 14:45:27 2008 (r184848) +++ head/lib/libc/sys/pipe.2 Tue Nov 11 14:55:59 2008 (r184849) @@ -39,7 +39,7 @@ .Sh SYNOPSIS .In unistd.h .Ft int -.Fn pipe "int *fildes" +.Fn pipe "int fildes[2]" .Sh DESCRIPTION The .Fn pipe @@ -96,11 +96,6 @@ Too many descriptors are active. The system file table is full. .It Bq Er ENOMEM Not enough kernel memory to establish a pipe. -.It Bq Er EFAULT -The -.Fa fildes -buffer is in an invalid area of the process's address -space. .El .Sh SEE ALSO .Xr sh 1 , Modified: head/sys/amd64/linux32/linux32_machdep.c ============================================================================== --- head/sys/amd64/linux32/linux32_machdep.c Tue Nov 11 14:45:27 2008 (r184848) +++ head/sys/amd64/linux32/linux32_machdep.c Tue Nov 11 14:55:59 2008 (r184849) @@ -977,33 +977,20 @@ linux_iopl(struct thread *td, struct lin int linux_pipe(struct thread *td, struct linux_pipe_args *args) { - int pip[2]; int error; - register_t reg_rdx; + int fildes[2]; #ifdef DEBUG if (ldebug(pipe)) printf(ARGS(pipe, "*")); #endif - reg_rdx = td->td_retval[1]; - error = pipe(td, 0); - if (error) { - td->td_retval[1] = reg_rdx; - return (error); - } - - pip[0] = td->td_retval[0]; - pip[1] = td->td_retval[1]; - error = copyout(pip, args->pipefds, 2 * sizeof(int)); - if (error) { - td->td_retval[1] = reg_rdx; + error = kern_pipe(td, fildes); + if (error) return (error); - } - td->td_retval[1] = reg_rdx; - td->td_retval[0] = 0; - return (0); + /* XXX: Close descriptors on error. */ + return (copyout(fildes, args->pipefds, sizeof fildes)); } int Modified: head/sys/i386/linux/linux_machdep.c ============================================================================== --- head/sys/i386/linux/linux_machdep.c Tue Nov 11 14:45:27 2008 (r184848) +++ head/sys/i386/linux/linux_machdep.c Tue Nov 11 14:55:59 2008 (r184849) @@ -813,29 +813,19 @@ int linux_pipe(struct thread *td, struct linux_pipe_args *args) { int error; - int reg_edx; + int fildes[2]; #ifdef DEBUG if (ldebug(pipe)) printf(ARGS(pipe, "*")); #endif - reg_edx = td->td_retval[1]; - error = pipe(td, 0); - if (error) { - td->td_retval[1] = reg_edx; - return (error); - } - - error = copyout(td->td_retval, args->pipefds, 2*sizeof(int)); - if (error) { - td->td_retval[1] = reg_edx; + error = kern_pipe(td, fildes); + if (error) return (error); - } - td->td_retval[1] = reg_edx; - td->td_retval[0] = 0; - return (0); + /* XXX: Close descriptors on error. */ + return (copyout(fildes, args->pipefds, sizeof fildes)); } int Modified: head/sys/kern/sys_pipe.c ============================================================================== --- head/sys/kern/sys_pipe.c Tue Nov 11 14:45:27 2008 (r184848) +++ head/sys/kern/sys_pipe.c Tue Nov 11 14:55:59 2008 (r184849) @@ -108,6 +108,7 @@ __FBSDID("$FreeBSD$"); #include <sys/poll.h> #include <sys/selinfo.h> #include <sys/signalvar.h> +#include <sys/syscallsubr.h> #include <sys/sysctl.h> #include <sys/sysproto.h> #include <sys/pipe.h> @@ -307,13 +308,8 @@ pipe_zone_fini(void *mem, int size) * The pipe system call for the DTYPE_PIPE type of pipes. If we fail, let * the zone pick up the pieces via pipeclose(). */ -/* ARGSUSED */ int -pipe(td, uap) - struct thread *td; - struct pipe_args /* { - int dummy; - } */ *uap; +kern_pipe(struct thread *td, int fildes[2]) { struct filedesc *fdp = td->td_proc->p_fd; struct file *rf, *wf; @@ -357,7 +353,7 @@ pipe(td, uap) return (error); } /* An extra reference on `rf' has been held for us by falloc(). */ - td->td_retval[0] = fd; + fildes[0] = fd; /* * Warning: once we've gotten past allocation of the fd for the @@ -368,7 +364,7 @@ pipe(td, uap) finit(rf, FREAD | FWRITE, DTYPE_PIPE, rpipe, &pipeops); error = falloc(td, &wf, &fd); if (error) { - fdclose(fdp, rf, td->td_retval[0], td); + fdclose(fdp, rf, fildes[0], td); fdrop(rf, td); /* rpipe has been closed by fdrop(). */ pipeclose(wpipe); @@ -377,12 +373,29 @@ pipe(td, uap) /* An extra reference on `wf' has been held for us by falloc(). */ finit(wf, FREAD | FWRITE, DTYPE_PIPE, wpipe, &pipeops); fdrop(wf, td); - td->td_retval[1] = fd; + fildes[1] = fd; fdrop(rf, td); return (0); } +/* ARGSUSED */ +int +pipe(struct thread *td, struct pipe_args *uap) +{ + int error; + int fildes[2]; + + error = kern_pipe(td, fildes); + if (error) + return (error); + + td->td_retval[0] = fildes[0]; + td->td_retval[1] = fildes[1]; + + return (0); +} + /* * Allocate kva for pipe circular buffer, the space is pageable * This routine will 'realloc' the size of a pipe safely, if it fails Modified: head/sys/sys/syscallsubr.h ============================================================================== --- head/sys/sys/syscallsubr.h Tue Nov 11 14:45:27 2008 (r184848) +++ head/sys/sys/syscallsubr.h Tue Nov 11 14:55:59 2008 (r184849) @@ -142,6 +142,7 @@ int kern_openat(struct thread *td, int f enum uio_seg pathseg, int flags, int mode); int kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name); +int kern_pipe(struct thread *td, int fildes[2]); int kern_preadv(struct thread *td, int fd, struct uio *auio, off_t offset); int kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data);
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