From 3112e9d48546c4c7b13a53224e8907a102ab2b0e Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Thu, 12 Mar 2009 13:45:55 +0000 Subject: MFC r189283: Correct types of variables used to track amount of allocated SysV shared memory from int to size_t. Implement a workaround for current ABI not allowing to properly save size for and report more then 2GB sized segment of shared memory. This makes it possible to use > 2 GB shared memory segments on 64bit architectures. Please note the new BUGS section in shmctl(2) and UPDATING note for limitations of this temporal solution. MFC r189398: Systematically use vm_size_t to specify the size of the segment for VM KPI. Do not overload the local variable size in kern_shmat() due to vm_size_t change. Fix style bug by adding explicit comparision with 0. MFC r189399: Improve the grammar and wording in the changes to shmctl(2) manpage. Put an UPDATING entry and bump __FreeBSD_version for the change. --- sys/kern/sysv_shm.c | 26 +++++++++++++++----------- sys/sys/param.h | 2 +- sys/sys/shm.h | 1 + 3 files changed, 17 insertions(+), 12 deletions(-) (limited to 'sys') diff --git a/sys/kern/sysv_shm.c b/sys/kern/sysv_shm.c index 574c3dee6a61..921b4fc3e634 100644 --- a/sys/kern/sysv_shm.c +++ b/sys/kern/sysv_shm.c @@ -121,7 +121,8 @@ static sy_call_t *shmcalls[] = { #define SHMSEG_ALLOCATED 0x0800 #define SHMSEG_WANTED 0x1000 -static int shm_last_free, shm_nused, shm_committed, shmalloced; +static int shm_last_free, shm_nused, shmalloced; +vm_size_t shm_committed; static struct shmid_kernel *shmsegs; struct shmmap_state { @@ -244,13 +245,13 @@ static void shm_deallocate_segment(shmseg) struct shmid_kernel *shmseg; { - size_t size; + vm_size_t size; GIANT_REQUIRED; vm_object_deallocate(shmseg->u.shm_internal); shmseg->u.shm_internal = NULL; - size = round_page(shmseg->u.shm_segsz); + size = round_page(shmseg->shm_bsegsz); shm_committed -= btoc(size); shm_nused--; shmseg->u.shm_perm.mode = SHMSEG_FREE; @@ -264,13 +265,13 @@ shm_delete_mapping(struct vmspace *vm, struct shmmap_state *shmmap_s) { struct shmid_kernel *shmseg; int segnum, result; - size_t size; + vm_size_t size; GIANT_REQUIRED; segnum = IPCID_TO_IX(shmmap_s->shmid); shmseg = &shmsegs[segnum]; - size = round_page(shmseg->u.shm_segsz); + size = round_page(shmseg->shm_bsegsz); result = vm_map_remove(&vm->vm_map, shmmap_s->va, shmmap_s->va + size); if (result != KERN_SUCCESS) return (EINVAL); @@ -361,8 +362,8 @@ kern_shmat(td, shmid, shmaddr, shmflg) mtx_lock(&Giant); shmmap_s = p->p_vmspace->vm_shm; if (shmmap_s == NULL) { - size = shminfo.shmseg * sizeof(struct shmmap_state); - shmmap_s = malloc(size, M_SHM, M_WAITOK); + shmmap_s = malloc(shminfo.shmseg * sizeof(struct shmmap_state), + M_SHM, M_WAITOK); for (i = 0; i < shminfo.shmseg; i++) shmmap_s[i].shmid = -1; p->p_vmspace->vm_shm = shmmap_s; @@ -390,7 +391,7 @@ kern_shmat(td, shmid, shmaddr, shmflg) error = EMFILE; goto done2; } - size = round_page(shmseg->u.shm_segsz); + size = round_page(shmseg->shm_bsegsz); #ifdef VM_PROT_READ_IS_EXEC prot = VM_PROT_READ | VM_PROT_EXECUTE; #else @@ -422,7 +423,8 @@ kern_shmat(td, shmid, shmaddr, shmflg) vm_object_reference(shmseg->u.shm_internal); rv = vm_map_find(&p->p_vmspace->vm_map, shmseg->u.shm_internal, - 0, &attach_va, size, (flags & MAP_FIXED)?0:1, prot, prot, 0); + 0, &attach_va, size, (flags & MAP_FIXED) ? VMFS_NO_SPACE : + VMFS_ANY_SPACE, prot, prot, 0); if (rv != KERN_SUCCESS) { vm_object_deallocate(shmseg->u.shm_internal); error = ENOMEM; @@ -705,7 +707,7 @@ shmget_existing(td, uap, mode, segnum) if (error != 0) return (error); #endif - if (uap->size && uap->size > shmseg->u.shm_segsz) + if (uap->size != 0 && uap->size > shmseg->shm_bsegsz) return (EINVAL); td->td_retval[0] = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm); return (0); @@ -717,7 +719,8 @@ shmget_allocate_segment(td, uap, mode) struct shmget_args *uap; int mode; { - int i, segnum, shmid, size; + int i, segnum, shmid; + size_t size; struct ucred *cred = td->td_ucred; struct shmid_kernel *shmseg; vm_object_t shm_object; @@ -775,6 +778,7 @@ shmget_allocate_segment(td, uap, mode) shmseg->u.shm_perm.mode = (shmseg->u.shm_perm.mode & SHMSEG_WANTED) | (mode & ACCESSPERMS) | SHMSEG_ALLOCATED; shmseg->u.shm_segsz = uap->size; + shmseg->shm_bsegsz = uap->size; shmseg->u.shm_cpid = td->td_proc->p_pid; shmseg->u.shm_lpid = shmseg->u.shm_nattch = 0; shmseg->u.shm_atime = shmseg->u.shm_dtime = 0; diff --git a/sys/sys/param.h b/sys/sys/param.h index a23d3b941105..17d2a85e70ce 100644 --- a/sys/sys/param.h +++ b/sys/sys/param.h @@ -57,7 +57,7 @@ * is created, otherwise 1. */ #undef __FreeBSD_version -#define __FreeBSD_version 701104 /* Master, propagated to newvers */ +#define __FreeBSD_version 701105 /* Master, propagated to newvers */ #ifndef LOCORE #include diff --git a/sys/sys/shm.h b/sys/sys/shm.h index 88eaf0624d0f..8bd8b50257a1 100644 --- a/sys/sys/shm.h +++ b/sys/sys/shm.h @@ -108,6 +108,7 @@ struct shminfo { struct shmid_kernel { struct shmid_ds u; struct label *label; /* MAC label */ + size_t shm_bsegsz; }; extern struct shminfo shminfo; -- cgit v1.3