[Qemu-devel] [PATCH] Fix and cleanup IPCOP_shm* ipc calls handling

["Kirill A. Shutemov" <kirill@shutemov.name>]

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
 linux-user/syscall.c |  282 +++++++++++++++++++++++++++++++++++++++----------
 1 files changed, 224 insertions(+), 58 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 1a09d90..d1fccb4 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -2109,6 +2109,206 @@ end:
     return ret;
 }
 
+struct target_shmid_ds
+{
+    struct target_ipc_perm shm_perm;
+    abi_ulong shm_segsz;
+    abi_ulong shm_atime;
+#if TARGET_ABI_BITS == 32
+    abi_ulong __unused1;
+#endif
+    abi_ulong shm_dtime;
+#if TARGET_ABI_BITS == 32
+    abi_ulong __unused2;
+#endif
+    abi_ulong shm_ctime;
+#if TARGET_ABI_BITS == 32
+    abi_ulong __unused3;
+#endif
+    int shm_cpid;
+    int shm_lpid;
+    abi_ulong shm_nattch;
+    unsigned long int __unused4;
+    unsigned long int __unused5;
+};
+
+static inline abi_long target_to_host_shmid_ds(struct shmid_ds *host_sd,
+                                               abi_ulong target_addr)
+{
+    struct target_shmid_ds *target_sd;
+
+    if (!lock_user_struct(VERIFY_READ, target_sd, target_addr, 1))
+        return -TARGET_EFAULT;
+    if (target_to_host_ipc_perm(&(host_sd->shm_perm), target_addr))
+        return -TARGET_EFAULT;
+    __put_user(target_sd->shm_segsz, &host_sd->shm_segsz);
+    __put_user(target_sd->shm_atime, &host_sd->shm_atime);
+    __put_user(target_sd->shm_dtime, &host_sd->shm_dtime);
+    __put_user(target_sd->shm_ctime, &host_sd->shm_ctime);
+    __put_user(target_sd->shm_cpid, &host_sd->shm_cpid);
+    __put_user(target_sd->shm_lpid, &host_sd->shm_lpid);
+    __put_user(target_sd->shm_nattch, &host_sd->shm_nattch);
+    unlock_user_struct(target_sd, target_addr, 0);
+    return 0;
+}
+
+static inline abi_long host_to_target_shmid_ds(abi_ulong target_addr,
+                                               struct shmid_ds *host_sd)
+{
+    struct target_shmid_ds *target_sd;
+
+    if (!lock_user_struct(VERIFY_WRITE, target_sd, target_addr, 0))
+        return -TARGET_EFAULT;
+    if (host_to_target_ipc_perm(target_addr, &(host_sd->shm_perm)))
+        return -TARGET_EFAULT;
+    __put_user(host_sd->shm_segsz, &target_sd->shm_segsz);
+    __put_user(host_sd->shm_atime, &target_sd->shm_atime);
+    __put_user(host_sd->shm_dtime, &target_sd->shm_dtime);
+    __put_user(host_sd->shm_ctime, &target_sd->shm_ctime);
+    __put_user(host_sd->shm_cpid, &target_sd->shm_cpid);
+    __put_user(host_sd->shm_lpid, &target_sd->shm_lpid);
+    __put_user(host_sd->shm_nattch, &target_sd->shm_nattch);
+    unlock_user_struct(target_sd, target_addr, 1);
+    return 0;
+}
+
+struct  target_shminfo {
+    abi_ulong shmmax;
+    abi_ulong shmmin;
+    abi_ulong shmmni;
+    abi_ulong shmseg;
+    abi_ulong shmall;
+};
+
+static inline abi_long host_to_target_shminfo(abi_ulong target_addr,
+                                              struct shminfo *host_shminfo)
+{
+    struct target_shminfo *target_shminfo;
+    if (!lock_user_struct(VERIFY_WRITE, target_shminfo, target_addr, 0))
+        return -TARGET_EFAULT;
+    __put_user(host_shminfo->shmmax, &target_shminfo->shmmax);
+    __put_user(host_shminfo->shmmin, &target_shminfo->shmmin);
+    __put_user(host_shminfo->shmmni, &target_shminfo->shmmni);
+    __put_user(host_shminfo->shmseg, &target_shminfo->shmseg);
+    __put_user(host_shminfo->shmall, &target_shminfo->shmall);
+    unlock_user_struct(target_shminfo, target_addr, 1);
+}
+
+struct target_shm_info {
+    int used_ids;
+    abi_ulong shm_tot;
+    abi_ulong shm_rss;
+    abi_ulong shm_swp;
+    abi_ulong swap_attempts;
+    abi_ulong swap_successes;
+};
+
+static inline abi_long host_to_target_shm_info(abi_ulong target_addr,
+                                               struct shm_info *host_shm_info)
+{
+    struct target_shm_info *target_shm_info;
+    if (!lock_user_struct(VERIFY_WRITE, target_shm_info, target_addr, 0))
+        return -TARGET_EFAULT;
+    __put_user(host_shm_info->used_ids, &target_shm_info->used_ids);
+    __put_user(host_shm_info->shm_tot, &target_shm_info->shm_tot);
+    __put_user(host_shm_info->shm_rss, &target_shm_info->shm_rss);
+    __put_user(host_shm_info->shm_swp, &target_shm_info->shm_swp);
+    __put_user(host_shm_info->swap_attempts, &target_shm_info->swap_attempts);
+    __put_user(host_shm_info->swap_successes, &target_shm_info->swap_successes);
+    unlock_user_struct(target_shm_info, target_addr, 1);
+}
+
+static inline abi_long do_shmctl(int shmid, int cmd, abi_long buf)
+{
+    struct shmid_ds dsarg;
+    struct shminfo shminfo;
+    struct shm_info shm_info;
+    abi_long ret = -TARGET_EINVAL;
+
+    cmd &= 0xff;
+
+    switch(cmd) {
+    case IPC_STAT:
+    case IPC_SET:
+    case SHM_STAT:
+        if (target_to_host_shmid_ds(&dsarg, buf))
+            return -TARGET_EFAULT;
+        ret = get_errno(shmctl(shmid, cmd, &dsarg));
+        if (host_to_target_shmid_ds(buf, &dsarg))
+            return -TARGET_EFAULT;
+        break;
+    case IPC_INFO:
+        ret = get_errno(shmctl(shmid, cmd, (struct shmid_ds *)&shminfo));
+        if (host_to_target_shminfo(buf, &shminfo))
+            return -TARGET_EFAULT;
+        break;
+    case SHM_INFO:
+        ret = get_errno(shmctl(shmid, cmd, (struct shmid_ds *)&shm_info));
+        if (host_to_target_shm_info(buf, &shm_info))
+            return -TARGET_EFAULT;
+        break;
+    case IPC_RMID:
+    case SHM_LOCK:
+    case SHM_UNLOCK:
+        ret = get_errno(shmctl(shmid, cmd, NULL));
+        break;
+    }
+
+    return ret;
+}
+
+static inline abi_long do_shmat(int shmid, abi_ulong shmaddr, int shmflg,
+                                unsigned long *raddr)
+{
+    abi_long ret;
+    struct shmid_ds shm_info;
+    int i;
+
+    /* SHM_* flags are the same on all linux platforms */
+    *raddr = (unsigned long) shmat(shmid, g2h(shmaddr), shmflg);
+
+    if (*raddr == -1) {
+        return get_errno(*raddr);
+    }
+
+    /* 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 */
+        shmdt((void *) *raddr);
+        return get_errno(ret);
+    }
+
+    page_set_flags(h2g(*raddr), h2g(*raddr) + shm_info.shm_segsz,
+                   PAGE_VALID | PAGE_READ |
+                   ((shmflg & SHM_RDONLY)? 0 : PAGE_WRITE));
+
+    for (i = 0; i < N_SHM_REGIONS; i++) {
+        if (shm_regions[i].start == 0) {
+            shm_regions[i].start = h2g(*raddr);
+            shm_regions[i].size = shm_info.shm_segsz;
+            break;
+        }
+    }
+
+    return 0;
+}
+
+static inline abi_long do_shmdt(abi_ulong shmaddr)
+{
+    int i;
+
+    for (i = 0; i < N_SHM_REGIONS; ++i) {
+        if (shm_regions[i].start == shmaddr) {
+            shm_regions[i].start = 0;
+            page_set_flags(shmaddr, shm_regions[i].size, 0);
+            break;
+        }
+    }
+
+    return get_errno(shmdt(g2h(shmaddr)));
+}
+
 #ifdef TARGET_NR_ipc
 /* ??? This only works with linear mappings.  */
 /* do_ipc() must return target values and target errnos. */
@@ -2118,8 +2318,6 @@ static abi_long do_ipc(unsigned int call, int first,
 {
     int version;
     abi_long ret = 0;
-    struct shmid_ds shm_info;
-    int i;
 
     version = call >> 16;
     call &= 0xffff;
@@ -2174,72 +2372,40 @@ static abi_long do_ipc(unsigned int call, int first,
         break;
 
     case IPCOP_shmat:
-        {
-            abi_ulong raddr;
-            void *host_addr;
-            /* SHM_* flags are the same on all linux platforms */
-            host_addr = shmat(first, (void *)g2h(ptr), second);
-            if (host_addr == (void *)-1) {
-                ret = get_errno((long)host_addr);
-                break;
-            }
-            raddr = h2g((unsigned long)host_addr);
-            /* find out the length of the shared memory segment */
-            
-            ret = get_errno(shmctl(first, IPC_STAT, &shm_info));
-            if (is_error(ret)) {
-                /* can't get length, bail out */
-                shmdt(host_addr);
-                break;
-            }
-            page_set_flags(raddr, raddr + shm_info.shm_segsz,
-                           PAGE_VALID | PAGE_READ |
-                           ((second & SHM_RDONLY)? 0: PAGE_WRITE));
-            for (i = 0; i < N_SHM_REGIONS; ++i) {
-                if (shm_regions[i].start == 0) {
-                    shm_regions[i].start = raddr;
-                    shm_regions[i].size = shm_info.shm_segsz;
+        switch (version) {
+        default:
+            {
+                unsigned long raddr;
+
+                ret = do_shmat(first, ptr, second, &raddr);
+                if (ret)
                     break;
-                }
+
+                ret = put_user_ual(raddr, third);
+                break;
             }
-            if (put_user_ual(raddr, third))
-                return -TARGET_EFAULT;
-            ret = 0;
+        case 1:
+            ret = -TARGET_EINVAL;
+            break;
         }
-	break;
+        break;
+
     case IPCOP_shmdt:
-	for (i = 0; i < N_SHM_REGIONS; ++i) {
-	    if (shm_regions[i].start == ptr) {
-		shm_regions[i].start = 0;
-		page_set_flags(ptr, shm_regions[i].size, 0);
-		break;
-	    }
-	}
-	ret = get_errno(shmdt((void *)g2h(ptr)));
-	break;
+        ret = do_shmdt(ptr);
+        break;
 
     case IPCOP_shmget:
-	/* IPC_* flag values are the same on all linux platforms */
-	ret = get_errno(shmget(first, second, third));
-	break;
+        ret = get_errno(shmget(first, second, third));
+        break;
 
-	/* IPC_* and SHM_* command values are the same on all linux platforms */
     case IPCOP_shmctl:
-        switch(second) {
-        case IPC_RMID:
-        case SHM_LOCK:
-        case SHM_UNLOCK:
-            ret = get_errno(shmctl(first, second, NULL));
-            break;
-        default:
-            goto unimplemented;
-        }
+        ret = do_shmctl(first, second, third);
         break;
+
     default:
-    unimplemented:
-	gemu_log("Unsupported ipc call: %d (version %d)\n", call, version);
-	ret = -TARGET_ENOSYS;
-	break;
+        gemu_log("Unsupported ipc call: %d (version %d)\n", call, version);
+        ret = -TARGET_ENOSYS;
+        break;
     }
     return ret;
 }
-- 
1.5.6.5.GIT