Merge remote-tracking branch 'remotes/bsdimp/tags/pull-bsd-user-20210910' into staging

This series of patches gets me to the point that I can run "Hello World" on i386
and x86_64. This is for static binaries only, that are relatively small, but
it's better than the 100% instant mmap failre that is the current state of all
things bsd-user in upstream qemu. Future patch sets will refine this, add
the missing system calls, fix bugs preventing more sophisticated programms
from running and add a bunch of new architecture support.

There's three large themes in these patches, though the changes that
represent them are interrelated making it hard to separate out further.
1. Reorganization to support multiple OS and architectures (though I've only
   tested FreeBSD, other BSDs might not even compile yet).
2. Diff reduction with the bsd-user fork for several files. These diffs include
   changes that borrowed from linux-user as well as changes to make things work
   on FreeBSD. The records keeping when this was done, however, was poor at
   best, so many of the specific borrowings are going unacknowledged here, apart
   from this general ack. These diffs also include some minor code shuffling.
   Some of the changes are done specifically to make it easier to rebase
   the bsd-user fork's changes when these land in the tree (a number of changes
   have been pushed there to make this more possible).
3. Filling in the missing pieces to make things work. There's many changes to
   elfload to make it load things in the right places, to find the interpreter
   better, etc. There's changes to mmap.c to make the mappings work better and
   there's changes to main.c that were inspired, at least, by now-ancient changes
   to linux-user's main.c.

I ran checkpatch.pl on this, and there's 350-odd errors it identifies (the vast
majoirty come from BSD's fetish for tabs), so there will need to be a V2 to fix
this at the very least. In addition, the change set is big (about +~4.5k/-~2.5k
lines), so I anticipate some iteration as well just based on its sheer
size. I've tried to keep each set small to make it easy to review in isolation,
but I've also allowed some interrelated ones to get a little bigger than I'd
normally like. I've not done the customary documentation of the expected
checkpatch.pl output because it is large, and because I wanted to get review
of the other parts rolling to get this project unstuck. Future versions of the
patch will document the expected output.

In addition, I noticed a number of places where I could modernize to make the
code match things like linux-user better. I've resisted the urge to do these at
this time, since it would complicate merging the other ~30k lines of diff that
remains after this batch. Future batches should generally be smaller once this
one has landed since they are, by and large, either a bunch of new files to
support armv7, aarch64, riscv64, mips, mipsel, mips64, ppc, ppc64 and ppc64le,
or are adding system calls, which can be done individually or small groups. I've
removed sparc and sparc64 support as they've been removed from FreeBSD and
have been near totally busted for years.

Stacey Son did the bulk of this work originally, but since I had to move things
around so much and/or retool that work in non-trivial ways, I've kept myself as
author, and added his signed-off-by line. I'm unsure of the qemu standard
practice for this, but am happy to learn if this is too far outside its current
mainstream. For a while Sean Bruno did the merges from upstream, and he's
credited using his signed-off-by in appropriate places, though for this patch
set there's only a few. I've tried to ensure that others who have work in
individual patches that I've aggregated together also are reflected in their
signed-off-by. Given the chaotic stat of the upstream repo for its early
history, this may be the best that can be reconstructed at this late date. Most
of these files are 'foundational' so have existed from the earliest days when
record keeping wasn't quite what I'd wish for in hindsight. There was only
really one change that I could easily cherry-pick (Colin's), so I did that.

# gpg: Signature made Fri 10 Sep 2021 21:24:08 BST
# gpg:                using RSA key 2035F894B00AA3CF7CCDE1B76C1CD1287DB01100
# gpg: Good signature from "Warner Losh <wlosh@netflix.com>" [unknown]
# gpg:                 aka "Warner Losh <imp@bsdimp.com>" [unknown]
# gpg:                 aka "Warner Losh <imp@freebsd.org>" [unknown]
# gpg:                 aka "Warner Losh <imp@village.org>" [unknown]
# gpg:                 aka "Warner Losh <wlosh@bsdimp.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2035 F894 B00A A3CF 7CCD  E1B7 6C1C D128 7DB0 1100

* remotes/bsdimp/tags/pull-bsd-user-20210910: (42 commits)
  bsd-user: Update mapping to handle reserved and starting conditions
  bsd-user: Add '-0 argv0' option to bsd-user/main.c
  bsd-user: Implement interlock for atomic operations
  bsd-user: move gemu_log to later in the file
  bsd-user: Refactor load_elf_sections and is_target_elf_binary
  bsd-user: elfload.c style catch up patch
  bsd-user: add stubbed out core dump support
  bsd-user: Add target_os_user.h to capture the user/kernel structures
  bsd-user: Add target_arch_reg to describe a target's register set
  bsd-user: update debugging in mmap.c
  bsd-user: Rewrite target system call definintion glue
  bsd-user: Remove dead #ifdefs from elfload.c
  bsd-user: elf cleanup
  bsd-user: Add architecture specific signal tramp code
  bsd-user: Move stack initializtion into a per-os file.
  bsd-user: Implement --seed and initialize random state
  bsd-user: *BSD specific siginfo defintions
  bsd-user: Add system independent stack, data and text limiting
  bsd-user: Create target specific vmparam.h
  bsd-user: define max args in terms of pages
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

6 files changed, 403 insertions, 0 deletions

diff --git a/bsd-user/netbsd/host-os.h b/bsd-user/netbsd/host-os.h
new file mode 100644
index 0000000000..c0be51a7ef
--- /dev/null
+++ b/bsd-user/netbsd/host-os.h
@@ -0,0 +1,25 @@
+/*
+ *  NetBSD host dependent code and definitions
+ *
+ *  Copyright (c) 2013 Stacey D. Son
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _HOST_OS_H_
+#define _HOST_OS_H_
+
+#define HOST_DEFAULT_BSD_TYPE target_netbsd
+
+#endif /*!_HOST_OS_H_ */
diff --git a/bsd-user/netbsd/target_os_elf.h b/bsd-user/netbsd/target_os_elf.h
new file mode 100644
index 0000000000..21b475f458
--- /dev/null
+++ b/bsd-user/netbsd/target_os_elf.h
@@ -0,0 +1,146 @@
+/*
+ *  netbsd ELF definitions
+ *
+ *  Copyright (c) 2013 Stacey D. Son
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef _TARGET_OS_ELF_H_
+#define _TARGET_OS_ELF_H_
+
+#include "target_arch_elf.h"
+#include "elf.h"
+
+/* this flag is uneffective under linux too, should be deleted */
+#ifndef MAP_DENYWRITE
+#define MAP_DENYWRITE 0
+#endif
+
+/* should probably go in elf.h */
+#ifndef ELIBBAD
+#define ELIBBAD 80
+#endif
+
+#ifndef ELF_PLATFORM
+#define ELF_PLATFORM (NULL)
+#endif
+
+#ifndef ELF_HWCAP
+#define ELF_HWCAP 0
+#endif
+
+#ifdef TARGET_ABI32
+#undef ELF_CLASS
+#define ELF_CLASS ELFCLASS32
+#undef bswaptls
+#define bswaptls(ptr) bswap32s(ptr)
+#endif
+
+/* max code+data+bss space allocated to elf interpreter */
+#define INTERP_MAP_SIZE (32 * 1024 * 1024)
+
+/* max code+data+bss+brk space allocated to ET_DYN executables */
+#define ET_DYN_MAP_SIZE (128 * 1024 * 1024)
+
+/* Necessary parameters */
+#define TARGET_ELF_EXEC_PAGESIZE TARGET_PAGE_SIZE
+#define TARGET_ELF_PAGESTART(_v) ((_v) & \
+        ~(unsigned long)(TARGET_ELF_EXEC_PAGESIZE - 1))
+#define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE - 1))
+
+#define DLINFO_ITEMS 12
+
+static abi_ulong target_create_elf_tables(abi_ulong p, int argc, int envc,
+                                          abi_ulong stringp,
+                                          struct elfhdr *exec,
+                                          abi_ulong load_addr,
+                                          abi_ulong load_bias,
+                                          abi_ulong interp_load_addr,
+                                          struct image_info *info)
+{
+        abi_ulong sp;
+        int size;
+        abi_ulong u_platform;
+        const char *k_platform;
+        const int n = sizeof(elf_addr_t);
+
+        sp = p;
+        u_platform = 0;
+        k_platform = ELF_PLATFORM;
+        if (k_platform) {
+            size_t len = strlen(k_platform) + 1;
+            sp -= (len + n - 1) & ~(n - 1);
+            u_platform = sp;
+            /* FIXME - check return value of memcpy_to_target() for failure */
+            memcpy_to_target(sp, k_platform, len);
+        }
+        /*
+         * Force 16 byte _final_ alignment here for generality.
+         */
+        sp = sp & ~(abi_ulong)15;
+        size = (DLINFO_ITEMS + 1) * 2;
+        if (k_platform) {
+            size += 2;
+        }
+#ifdef DLINFO_ARCH_ITEMS
+        size += DLINFO_ARCH_ITEMS * 2;
+#endif
+        size += envc + argc + 2;
+        size += 1;                         /* argc itself */
+        size *= n;
+        if (size & 15) {
+            sp -= 16 - (size & 15);
+        }
+
+        /*
+         * NetBSD defines elf_addr_t as Elf32_Off / Elf64_Off
+         */
+#define NEW_AUX_ENT(id, val) do {               \
+            sp -= n; put_user_ual(val, sp);     \
+            sp -= n; put_user_ual(id, sp);      \
+          } while (0)
+
+        NEW_AUX_ENT(AT_NULL, 0);
+
+        /* There must be exactly DLINFO_ITEMS entries here.  */
+        NEW_AUX_ENT(AT_PHDR, (abi_ulong)(load_addr + exec->e_phoff));
+        NEW_AUX_ENT(AT_PHENT, (abi_ulong)(sizeof(struct elf_phdr)));
+        NEW_AUX_ENT(AT_PHNUM, (abi_ulong)(exec->e_phnum));
+        NEW_AUX_ENT(AT_PAGESZ, (abi_ulong)(TARGET_PAGE_SIZE));
+        NEW_AUX_ENT(AT_BASE, (abi_ulong)(interp_load_addr));
+        NEW_AUX_ENT(AT_FLAGS, (abi_ulong)0);
+        NEW_AUX_ENT(AT_ENTRY, load_bias + exec->e_entry);
+        NEW_AUX_ENT(AT_UID, (abi_ulong)getuid());
+        NEW_AUX_ENT(AT_EUID, (abi_ulong)geteuid());
+        NEW_AUX_ENT(AT_GID, (abi_ulong)getgid());
+        NEW_AUX_ENT(AT_EGID, (abi_ulong)getegid());
+        NEW_AUX_ENT(AT_HWCAP, (abi_ulong)ELF_HWCAP);
+        NEW_AUX_ENT(AT_CLKTCK, (abi_ulong)sysconf(_SC_CLK_TCK));
+        if (k_platform) {
+            NEW_AUX_ENT(AT_PLATFORM, u_platform);
+        }
+#ifdef ARCH_DLINFO
+        /*
+         * ARCH_DLINFO must come last so platform specific code can enforce
+         * special alignment requirements on the AUXV if necessary (eg. PPC).
+         */
+        ARCH_DLINFO;
+#endif
+#undef NEW_AUX_ENT
+
+        sp = loader_build_argptr(envc, argc, sp, stringp);
+        return sp;
+}
+
+#endif /* _TARGET_OS_ELF_H_ */
diff --git a/bsd-user/netbsd/target_os_siginfo.h b/bsd-user/netbsd/target_os_siginfo.h
new file mode 100644
index 0000000000..667c19cc7c
--- /dev/null
+++ b/bsd-user/netbsd/target_os_siginfo.h
@@ -0,0 +1,82 @@
+#ifndef _TARGET_OS_SIGINFO_H_
+#define _TARGET_OS_SIGINFO_H_
+
+#define TARGET_NSIG     32  /* counting 0; could be 33 (mask is 1-32) */
+#define TARGET_NSIG_BPW     (sizeof(uint32_t) * 8)
+#define TARGET_NSIG_WORDS   (TARGET_NSIG / TARGET_NSIG_BPW)
+
+/* this struct defines a stack used during syscall handling */
+typedef struct target_sigaltstack {
+    abi_long    ss_sp;
+    abi_ulong   ss_size;
+    abi_long    ss_flags;
+} target_stack_t;
+
+typedef struct {
+    uint32_t __bits[TARGET_NSIG_WORDS];
+} target_sigset_t
+
+struct target_sigaction {
+    abi_ulong   _sa_handler;
+    int32_t     sa_flags;
+    target_sigset_t sa_mask;
+};
+
+/* Compare to sys/siginfo.h */
+typedef union target_sigval {
+    int         sival_int;
+    abi_ulong   sival_ptr;
+} target_sigval_t;
+
+struct target_ksiginfo {
+    int32_t     _signo;
+    int32_t     _code;
+    int32_t     _errno;
+#if TARGET_ABI_BITS == 64
+    int32_t     _pad;
+#endif
+    union {
+        struct {
+            int32_t             _pid;
+            int32_t             _uid;
+            target_sigval_t    _value;
+        } _rt;
+
+        struct {
+            int32_t             _pid;
+            int32_t             _uid;
+            int32_t             _struct;
+            /* clock_t          _utime; */
+            /* clock_t          _stime; */
+        } _child;
+
+        struct {
+            abi_ulong           _addr;
+            int32_t             _trap;
+        } _fault;
+
+        struct {
+            long                _band;
+            int                 _fd;
+        } _poll;
+    } _reason;
+};
+
+typedef union target_siginfo {
+    int8_t     si_pad[128];
+    struct     target_ksiginfo  _info;
+} target_siginfo_t;
+
+#define target_si_signo     _info._signo
+#define target_si_code      _info._code
+#define target_si_errno     _info._errno
+#define target_si_addr      _info._reason._fault._addr
+
+#define TARGET_SEGV_MAPERR  1
+#define TARGET_SEGV_ACCERR  2
+
+#define TARGET_TRAP_BRKPT   1
+#define TARGET_TRAP_TRACE   2
+
+
+#endif /* ! _TARGET_OS_SIGINFO_H_ */
diff --git a/bsd-user/netbsd/target_os_signal.h b/bsd-user/netbsd/target_os_signal.h
new file mode 100644
index 0000000000..a373922f7e
--- /dev/null
+++ b/bsd-user/netbsd/target_os_signal.h
@@ -0,0 +1,69 @@
+#ifndef _TARGET_OS_SIGNAL_H_
+#define _TARGET_OS_SIGNAL_H_
+
+#include "target_os_siginfo.h"
+#include "target_arch_signal.h"
+
+#define TARGET_SIGHUP  1       /* hangup */
+#define TARGET_SIGINT  2       /* interrupt */
+#define TARGET_SIGQUIT 3       /* quit */
+#define TARGET_SIGILL  4       /* illegal instruction (not reset when caught) */
+#define TARGET_SIGTRAP 5       /* trace trap (not reset when caught) */
+#define TARGET_SIGABRT 6       /* abort() */
+#define TARGET_SIGIOT  SIGABRT /* compatibility */
+#define TARGET_SIGEMT  7       /* EMT instruction */
+#define TARGET_SIGFPE  8       /* floating point exception */
+#define TARGET_SIGKILL 9       /* kill (cannot be caught or ignored) */
+#define TARGET_SIGBUS  10      /* bus error */
+#define TARGET_SIGSEGV 11      /* segmentation violation */
+#define TARGET_SIGSYS  12      /* bad argument to system call */
+#define TARGET_SIGPIPE 13      /* write on a pipe with no one to read it */
+#define TARGET_SIGALRM 14      /* alarm clock */
+#define TARGET_SIGTERM 15      /* software termination signal from kill */
+#define TARGET_SIGURG  16      /* urgent condition on IO channel */
+#define TARGET_SIGSTOP 17      /* sendable stop signal not from tty */
+#define TARGET_SIGTSTP 18      /* stop signal from tty */
+#define TARGET_SIGCONT 19      /* continue a stopped process */
+#define TARGET_SIGCHLD 20      /* to parent on child stop or exit */
+#define TARGET_SIGTTIN 21      /* to readers pgrp upon background tty read */
+#define TARGET_SIGTTOU 22      /* like TTIN for out if (tp->t_local&LTOSTOP) */
+#define TARGET_SIGIO   23      /* input/output possible signal */
+#define TARGET_SIGXCPU 24      /* exceeded CPU time limit */
+#define TARGET_SIGXFSZ 25      /* exceeded file size limit */
+#define TARGET_SIGVTALRM 26    /* virtual time alarm */
+#define TARGET_SIGPROF   27    /* profiling time alarm */
+#define TARGET_SIGWINCH  28    /* window size changes */
+#define TARGET_SIGINFO   29    /* information request */
+#define TARGET_SIGUSR1   30    /* user defined signal 1 */
+#define TARGET_SIGUSR2   31    /* user defined signal 2 */
+
+/*
+ * Language spec says we must list exactly one parameter, even though we
+ * actually supply three.  Ugh!
+ */
+#define TARGET_SIG_DFL         ((void (*)(int))0)
+#define TARGET_SIG_IGN         ((void (*)(int))1)
+#define TARGET_SIG_ERR         ((void (*)(int))-1)
+
+#define TARGET_SA_ONSTACK   0x0001  /* take signal on signal stack */
+#define TARGET_SA_RESTART   0x0002  /* restart system on signal return */
+#define TARGET_SA_RESETHAND 0x0004  /* reset to SIG_DFL when taking signal */
+#define TARGET_SA_NODEFER   0x0010  /* don't mask the signal we're delivering */
+#define TARGET_SA_NOCLDWAIT 0x0020  /* don't create zombies (assign to pid 1) */
+#define TARGET_SA_USERTRAMP 0x0100  /* do not bounce off kernel's sigtramp */
+#define TARGET_SA_NOCLDSTOP 0x0008  /* do not generate SIGCHLD on child stop */
+#define TARGET_SA_SIGINFO   0x0040  /* generate siginfo_t */
+
+/*
+ * Flags for sigprocmask:
+ */
+#define TARGET_SIG_BLOCK       1       /* block specified signal set */
+#define TARGET_SIG_UNBLOCK     2       /* unblock specified signal set */
+#define TARGET_SIG_SETMASK     3       /* set specified signal set */
+
+#define TARGET_BADSIG       SIG_ERR
+
+#define TARGET_SS_ONSTACK 0x0001 /* take signals on alternate stack */
+#define TARGET_SS_DISABLE 0x0004 /* disable taking signals on alternate stack */
+
+#endif /* !_TARGET_OS_SIGNAL_H_ */
diff --git a/bsd-user/netbsd/target_os_stack.h b/bsd-user/netbsd/target_os_stack.h
new file mode 100644
index 0000000000..503279c1a9
--- /dev/null
+++ b/bsd-user/netbsd/target_os_stack.h
@@ -0,0 +1,56 @@
+/*
+ *  NetBSD setup_initial_stack() implementation.
+ *
+ *  Copyright (c) 2013-14 Stacey D. Son
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _TARGET_OS_STACK_H_
+#define _TARGET_OS_STACK_H_
+
+#include "target_arch_sigtramp.h"
+
+static inline int setup_initial_stack(struct bsd_binprm *bprm, abi_ulong *p,
+    abi_ulong *stringp)
+{
+    int i;
+    abi_ulong stack_base;
+
+    stack_base = (target_stkbas + target_stksiz) -
+                  MAX_ARG_PAGES * TARGET_PAGE_SIZE;
+    if (p) {
+        *p = stack_base;
+    }
+    if (stringp) {
+        *stringp = stack_base;
+    }
+
+    for (i = 0; i < MAX_ARG_PAGES; i++) {
+        if (bprm->page[i]) {
+            info->rss++;
+            if (!memcpy_to_target(stack_base, bprm->page[i],
+                        TARGET_PAGE_SIZE)) {
+                errno = EFAULT;
+                return -1;
+            }
+            g_free(bprm->page[i]);
+        }
+        stack_base += TARGET_PAGE_SIZE;
+    }
+
+    return 0;
+}
+
+#endif /* !_TARGET_OS_STACK_H_ */
diff --git a/bsd-user/netbsd/target_os_thread.h b/bsd-user/netbsd/target_os_thread.h
new file mode 100644
index 0000000000..904dd1bf78
--- /dev/null
+++ b/bsd-user/netbsd/target_os_thread.h
@@ -0,0 +1,25 @@
+/*
+ *  NetBSD thread dependent code and definitions
+ *
+ *  Copyright (c) 2013 Stacey D. Son
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _TARGET_OS_THREAD_H_
+#define _TARGET_OS_THREAD_H_
+
+#include "target_arch_thread.h"
+
+#endif /* !_TARGET_OS_THREAD_H_ */