From 91d5354a2ce810d848eca6ecf9da1027aeb2be6d Mon Sep 17 00:00:00 2001 From: John Baldwin Date: Wed, 4 Feb 2004 21:52:57 +0000 Subject: Locking for the per-process resource limits structure. - struct plimit includes a mutex to protect a reference count. The plimit structure is treated similarly to struct ucred in that is is always copy on write, so having a reference to a structure is sufficient to read from it without needing a further lock. - The proc lock protects the p_limit pointer and must be held while reading limits from a process to keep the limit structure from changing out from under you while reading from it. - Various global limits that are ints are not protected by a lock since int writes are atomic on all the archs we support and thus a lock wouldn't buy us anything. - All accesses to individual resource limits from a process are abstracted behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return either an rlimit, or the current or max individual limit of the specified resource from a process. - dosetrlimit() was renamed to kern_setrlimit() to match existing style of other similar syscall helper functions. - The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit() (it didn't used the stackgap when it should have) but uses lim_rlimit() and kern_setrlimit() instead. - The svr4 compat no longer uses the stackgap for resource limits calls, but uses lim_rlimit() and kern_setrlimit() instead. - The ibcs2 compat no longer uses the stackgap for resource limits. It also no longer uses the stackgap for accessing sysctl's for the ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result, ibcs2_sysconf() no longer needs Giant. - The p_rlimit macro no longer exists. Submitted by: mtm (mostly, I only did a few cleanups and catchups) Tested on: i386 Compiled on: alpha, amd64 --- sys/gnu/ext2fs/ext2_readwrite.c | 14 +++++++------- sys/gnu/fs/ext2fs/ext2_readwrite.c | 14 +++++++------- 2 files changed, 14 insertions(+), 14 deletions(-) (limited to 'sys/gnu') diff --git a/sys/gnu/ext2fs/ext2_readwrite.c b/sys/gnu/ext2fs/ext2_readwrite.c index ba798354f347..c40ae9898581 100644 --- a/sys/gnu/ext2fs/ext2_readwrite.c +++ b/sys/gnu/ext2fs/ext2_readwrite.c @@ -217,15 +217,15 @@ WRITE(ap) * file servers have no limits, I don't think it matters. */ td = uio->uio_td; - /* For p_rlimit. */ - mtx_assert(&Giant, MA_OWNED); - if (vp->v_type == VREG && td && - uio->uio_offset + uio->uio_resid > - td->td_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) { + if (vp->v_type == VREG && td != NULL) { PROC_LOCK(td->td_proc); - psignal(td->td_proc, SIGXFSZ); + if (uio->uio_offset + uio->uio_resid > + lim_cur(td->td_proc, RLIMIT_FSIZE)) { + psignal(td->td_proc, SIGXFSZ); + PROC_UNLOCK(td->td_proc); + return (EFBIG); + } PROC_UNLOCK(td->td_proc); - return (EFBIG); } resid = uio->uio_resid; diff --git a/sys/gnu/fs/ext2fs/ext2_readwrite.c b/sys/gnu/fs/ext2fs/ext2_readwrite.c index ba798354f347..c40ae9898581 100644 --- a/sys/gnu/fs/ext2fs/ext2_readwrite.c +++ b/sys/gnu/fs/ext2fs/ext2_readwrite.c @@ -217,15 +217,15 @@ WRITE(ap) * file servers have no limits, I don't think it matters. */ td = uio->uio_td; - /* For p_rlimit. */ - mtx_assert(&Giant, MA_OWNED); - if (vp->v_type == VREG && td && - uio->uio_offset + uio->uio_resid > - td->td_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) { + if (vp->v_type == VREG && td != NULL) { PROC_LOCK(td->td_proc); - psignal(td->td_proc, SIGXFSZ); + if (uio->uio_offset + uio->uio_resid > + lim_cur(td->td_proc, RLIMIT_FSIZE)) { + psignal(td->td_proc, SIGXFSZ); + PROC_UNLOCK(td->td_proc); + return (EFBIG); + } PROC_UNLOCK(td->td_proc); - return (EFBIG); } resid = uio->uio_resid; -- cgit v1.3