From 225a206c4474f8344c8f0c13b735c414d0f170c7 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 20 Aug 2023 09:24:14 -0700 Subject: [PATCH] linux-user: Move shmat and shmdt implementations to mmap.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Rename from do_* to target_*. Fix some minor checkpatch errors. Tested-by: Helge Deller Tested-by: Philippe Mathieu-Daudé Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Warner Losh Signed-off-by: Richard Henderson --- linux-user/mmap.c | 138 +++++++++++++++++++++++++++++++++++++++ linux-user/syscall.c | 143 ++--------------------------------------- linux-user/user-mmap.h | 4 ++ 3 files changed, 146 insertions(+), 139 deletions(-) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 9aab48d4a3..3aeacd1ecd 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -17,6 +17,7 @@ * along with this program; if not, see . */ #include "qemu/osdep.h" +#include #include "trace.h" #include "exec/log.h" #include "qemu.h" @@ -27,6 +28,14 @@ static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER; static __thread int mmap_lock_count; +#define N_SHM_REGIONS 32 + +static struct shm_region { + abi_ulong start; + abi_ulong size; + bool in_use; +} shm_regions[N_SHM_REGIONS]; + void mmap_lock(void) { if (mmap_lock_count++ == 0) { @@ -981,3 +990,132 @@ abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice) return ret; } + +#ifndef TARGET_FORCE_SHMLBA +/* + * For most architectures, SHMLBA is the same as the page size; + * some architectures have larger values, in which case they should + * define TARGET_FORCE_SHMLBA and provide a target_shmlba() function. + * This corresponds to the kernel arch code defining __ARCH_FORCE_SHMLBA + * and defining its own value for SHMLBA. + * + * The kernel also permits SHMLBA to be set by the architecture to a + * value larger than the page size without setting __ARCH_FORCE_SHMLBA; + * this means that addresses are rounded to the large size if + * SHM_RND is set but addresses not aligned to that size are not rejected + * as long as they are at least page-aligned. Since the only architecture + * which uses this is ia64 this code doesn't provide for that oddity. + */ +static inline abi_ulong target_shmlba(CPUArchState *cpu_env) +{ + return TARGET_PAGE_SIZE; +} +#endif + +abi_ulong target_shmat(CPUArchState *cpu_env, int shmid, + abi_ulong shmaddr, int shmflg) +{ + CPUState *cpu = env_cpu(cpu_env); + abi_ulong raddr; + void *host_raddr; + struct shmid_ds shm_info; + int i, ret; + abi_ulong shmlba; + + /* shmat pointers are always untagged */ + + /* find out the length of the shared memory segment */ + ret = get_errno(shmctl(shmid, IPC_STAT, &shm_info)); + if (is_error(ret)) { + /* can't get length, bail out */ + return ret; + } + + shmlba = target_shmlba(cpu_env); + + if (shmaddr & (shmlba - 1)) { + if (shmflg & SHM_RND) { + shmaddr &= ~(shmlba - 1); + } else { + return -TARGET_EINVAL; + } + } + if (!guest_range_valid_untagged(shmaddr, shm_info.shm_segsz)) { + return -TARGET_EINVAL; + } + + mmap_lock(); + + /* + * We're mapping shared memory, so ensure we generate code for parallel + * execution and flush old translations. This will work up to the level + * supported by the host -- anything that requires EXCP_ATOMIC will not + * be atomic with respect to an external process. + */ + if (!(cpu->tcg_cflags & CF_PARALLEL)) { + cpu->tcg_cflags |= CF_PARALLEL; + tb_flush(cpu); + } + + if (shmaddr) { + host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg); + } else { + abi_ulong mmap_start; + + /* In order to use the host shmat, we need to honor host SHMLBA. */ + mmap_start = mmap_find_vma(0, shm_info.shm_segsz, MAX(SHMLBA, shmlba)); + + if (mmap_start == -1) { + errno = ENOMEM; + host_raddr = (void *)-1; + } else { + host_raddr = shmat(shmid, g2h_untagged(mmap_start), + shmflg | SHM_REMAP); + } + } + + if (host_raddr == (void *)-1) { + mmap_unlock(); + return get_errno((intptr_t)host_raddr); + } + raddr = h2g((uintptr_t)host_raddr); + + page_set_flags(raddr, raddr + shm_info.shm_segsz - 1, + PAGE_VALID | PAGE_RESET | PAGE_READ | + (shmflg & SHM_RDONLY ? 0 : PAGE_WRITE)); + + for (i = 0; i < N_SHM_REGIONS; i++) { + if (!shm_regions[i].in_use) { + shm_regions[i].in_use = true; + shm_regions[i].start = raddr; + shm_regions[i].size = shm_info.shm_segsz; + break; + } + } + + mmap_unlock(); + return raddr; +} + +abi_long target_shmdt(abi_ulong shmaddr) +{ + int i; + abi_long rv; + + /* shmdt pointers are always untagged */ + + mmap_lock(); + + for (i = 0; i < N_SHM_REGIONS; ++i) { + if (shm_regions[i].in_use && shm_regions[i].start == shmaddr) { + shm_regions[i].in_use = false; + page_set_flags(shmaddr, shmaddr + shm_regions[i].size - 1, 0); + break; + } + } + rv = get_errno(shmdt(g2h_untagged(shmaddr))); + + mmap_unlock(); + + return rv; +} diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 8d96acd085..ff4eefe7fc 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -3725,14 +3725,6 @@ static abi_long do_socketcall(int num, abi_ulong vptr) } #endif -#define N_SHM_REGIONS 32 - -static struct shm_region { - abi_ulong start; - abi_ulong size; - bool in_use; -} shm_regions[N_SHM_REGIONS]; - #ifndef TARGET_SEMID64_DS /* asm-generic version of this struct */ struct target_semid64_ds @@ -4482,133 +4474,6 @@ static inline abi_long do_shmctl(int shmid, int cmd, abi_long buf) return ret; } -#ifndef TARGET_FORCE_SHMLBA -/* For most architectures, SHMLBA is the same as the page size; - * some architectures have larger values, in which case they should - * define TARGET_FORCE_SHMLBA and provide a target_shmlba() function. - * This corresponds to the kernel arch code defining __ARCH_FORCE_SHMLBA - * and defining its own value for SHMLBA. - * - * The kernel also permits SHMLBA to be set by the architecture to a - * value larger than the page size without setting __ARCH_FORCE_SHMLBA; - * this means that addresses are rounded to the large size if - * SHM_RND is set but addresses not aligned to that size are not rejected - * as long as they are at least page-aligned. Since the only architecture - * which uses this is ia64 this code doesn't provide for that oddity. - */ -static inline abi_ulong target_shmlba(CPUArchState *cpu_env) -{ - return TARGET_PAGE_SIZE; -} -#endif - -static abi_ulong do_shmat(CPUArchState *cpu_env, int shmid, - abi_ulong shmaddr, int shmflg) -{ - CPUState *cpu = env_cpu(cpu_env); - abi_ulong raddr; - void *host_raddr; - struct shmid_ds shm_info; - int i, ret; - abi_ulong shmlba; - - /* shmat pointers are always untagged */ - - /* find out the length of the shared memory segment */ - ret = get_errno(shmctl(shmid, IPC_STAT, &shm_info)); - if (is_error(ret)) { - /* can't get length, bail out */ - return ret; - } - - shmlba = target_shmlba(cpu_env); - - if (shmaddr & (shmlba - 1)) { - if (shmflg & SHM_RND) { - shmaddr &= ~(shmlba - 1); - } else { - return -TARGET_EINVAL; - } - } - if (!guest_range_valid_untagged(shmaddr, shm_info.shm_segsz)) { - return -TARGET_EINVAL; - } - - mmap_lock(); - - /* - * We're mapping shared memory, so ensure we generate code for parallel - * execution and flush old translations. This will work up to the level - * supported by the host -- anything that requires EXCP_ATOMIC will not - * be atomic with respect to an external process. - */ - if (!(cpu->tcg_cflags & CF_PARALLEL)) { - cpu->tcg_cflags |= CF_PARALLEL; - tb_flush(cpu); - } - - if (shmaddr) - host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg); - else { - abi_ulong mmap_start; - - /* In order to use the host shmat, we need to honor host SHMLBA. */ - mmap_start = mmap_find_vma(0, shm_info.shm_segsz, MAX(SHMLBA, shmlba)); - - if (mmap_start == -1) { - errno = ENOMEM; - host_raddr = (void *)-1; - } else - host_raddr = shmat(shmid, g2h_untagged(mmap_start), - shmflg | SHM_REMAP); - } - - if (host_raddr == (void *)-1) { - mmap_unlock(); - return get_errno((intptr_t)host_raddr); - } - raddr = h2g((uintptr_t)host_raddr); - - page_set_flags(raddr, raddr + shm_info.shm_segsz - 1, - PAGE_VALID | PAGE_RESET | PAGE_READ | - (shmflg & SHM_RDONLY ? 0 : PAGE_WRITE)); - - for (i = 0; i < N_SHM_REGIONS; i++) { - if (!shm_regions[i].in_use) { - shm_regions[i].in_use = true; - shm_regions[i].start = raddr; - shm_regions[i].size = shm_info.shm_segsz; - break; - } - } - - mmap_unlock(); - return raddr; -} - -static inline abi_long do_shmdt(abi_ulong shmaddr) -{ - int i; - abi_long rv; - - /* shmdt pointers are always untagged */ - - mmap_lock(); - - for (i = 0; i < N_SHM_REGIONS; ++i) { - if (shm_regions[i].in_use && shm_regions[i].start == shmaddr) { - shm_regions[i].in_use = false; - page_set_flags(shmaddr, shmaddr + shm_regions[i].size - 1, 0); - break; - } - } - rv = get_errno(shmdt(g2h_untagged(shmaddr))); - - mmap_unlock(); - - return rv; -} - #ifdef TARGET_NR_ipc /* ??? This only works with linear mappings. */ /* do_ipc() must return target values and target errnos. */ @@ -4695,7 +4560,7 @@ static abi_long do_ipc(CPUArchState *cpu_env, default: { abi_ulong raddr; - raddr = do_shmat(cpu_env, first, ptr, second); + raddr = target_shmat(cpu_env, first, ptr, second); if (is_error(raddr)) return get_errno(raddr); if (put_user_ual(raddr, third)) @@ -4708,7 +4573,7 @@ static abi_long do_ipc(CPUArchState *cpu_env, } break; case IPCOP_shmdt: - ret = do_shmdt(ptr); + ret = target_shmdt(ptr); break; case IPCOP_shmget: @@ -11008,11 +10873,11 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, #endif #ifdef TARGET_NR_shmat case TARGET_NR_shmat: - return do_shmat(cpu_env, arg1, arg2, arg3); + return target_shmat(cpu_env, arg1, arg2, arg3); #endif #ifdef TARGET_NR_shmdt case TARGET_NR_shmdt: - return do_shmdt(arg1); + return target_shmdt(arg1); #endif case TARGET_NR_fsync: return get_errno(fsync(arg1)); diff --git a/linux-user/user-mmap.h b/linux-user/user-mmap.h index 0f4883eb57..b94bcdcf83 100644 --- a/linux-user/user-mmap.h +++ b/linux-user/user-mmap.h @@ -58,4 +58,8 @@ abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong); void mmap_fork_start(void); void mmap_fork_end(int child); +abi_ulong target_shmat(CPUArchState *cpu_env, int shmid, + abi_ulong shmaddr, int shmflg); +abi_long target_shmdt(abi_ulong shmaddr); + #endif /* LINUX_USER_USER_MMAP_H */