OpenZFS 7431 - ZFS Channel Programs

Authored by: Chris Williamson <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: John Kennedy <[email protected]>
Reviewed by: Dan Kimmel <[email protected]>
Approved by: Garrett D'Amore <[email protected]>
Ported-by: Don Brady <[email protected]>
Ported-by: John Kennedy <[email protected]>

OpenZFS-issue: https://www.illumos.org/issues/7431
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/dfc11533

Porting Notes:
* The CLI long option arguments for '-t' and '-m' don't parse on linux
* Switched from kmem_alloc to vmem_alloc in zcp_lua_alloc
* Lua implementation is built as its own module (zlua.ko)
* Lua headers consumed directly by zfs code moved to 'include/sys/lua/'
* There is no native setjmp/longjump available in stock Linux kernel.
  Brought over implementations from illumos and FreeBSD
* The get_temporary_prop() was adapted due to VFS platform differences
* Use of inline functions in lua parser to reduce stack usage per C call
* Skip some ZFS Test Suite ZCP tests on sparc64 to avoid stack overflow

1 files changed, 289 insertions, 0 deletions

diff --git a/module/lua/ltablib.c b/module/lua/ltablib.c
new file mode 100644
index 000000000..d01b5ba07
--- /dev/null
+++ b/module/lua/ltablib.c
@@ -0,0 +1,289 @@
+/* BEGIN CSTYLED */
+/*
+** $Id: ltablib.c,v 1.65.1.2 2014/05/07 16:32:55 roberto Exp $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+
+#define ltablib_c
+#define LUA_LIB
+
+#include <sys/lua/lua.h>
+
+#include <sys/lua/lauxlib.h>
+#include <sys/lua/lualib.h>
+
+
+#define aux_getn(L,n)	(luaL_checktype(L, n, LUA_TTABLE), luaL_len(L, n))
+
+
+
+#if defined(LUA_COMPAT_MAXN)
+static int maxn (lua_State *L) {
+  lua_Number max = 0;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushnil(L);  /* first key */
+  while (lua_next(L, 1)) {
+    lua_pop(L, 1);  /* remove value */
+    if (lua_type(L, -1) == LUA_TNUMBER) {
+      lua_Number v = lua_tonumber(L, -1);
+      if (v > max) max = v;
+    }
+  }
+  lua_pushnumber(L, max);
+  return 1;
+}
+#endif
+
+
+static int tinsert (lua_State *L) {
+  int e = aux_getn(L, 1) + 1;  /* first empty element */
+  int pos;  /* where to insert new element */
+  switch (lua_gettop(L)) {
+    case 2: {  /* called with only 2 arguments */
+      pos = e;  /* insert new element at the end */
+      break;
+    }
+    case 3: {
+      int i;
+      pos = luaL_checkint(L, 2);  /* 2nd argument is the position */
+      luaL_argcheck(L, 1 <= pos && pos <= e, 2, "position out of bounds");
+      for (i = e; i > pos; i--) {  /* move up elements */
+        lua_rawgeti(L, 1, i-1);
+        lua_rawseti(L, 1, i);  /* t[i] = t[i-1] */
+      }
+      break;
+    }
+    default: {
+      return luaL_error(L, "wrong number of arguments to " LUA_QL("insert"));
+    }
+  }
+  lua_rawseti(L, 1, pos);  /* t[pos] = v */
+  return 0;
+}
+
+
+static int tremove (lua_State *L) {
+  int size = aux_getn(L, 1);
+  int pos = luaL_optint(L, 2, size);
+  if (pos != size)  /* validate 'pos' if given */
+    luaL_argcheck(L, 1 <= pos && pos <= size + 1, 1, "position out of bounds");
+  lua_rawgeti(L, 1, pos);  /* result = t[pos] */
+  for ( ; pos < size; pos++) {
+    lua_rawgeti(L, 1, pos+1);
+    lua_rawseti(L, 1, pos);  /* t[pos] = t[pos+1] */
+  }
+  lua_pushnil(L);
+  lua_rawseti(L, 1, pos);  /* t[pos] = nil */
+  return 1;
+}
+
+
+static void addfield (lua_State *L, luaL_Buffer *b, int i) {
+  lua_rawgeti(L, 1, i);
+  if (!lua_isstring(L, -1))
+    luaL_error(L, "invalid value (%s) at index %d in table for "
+                  LUA_QL("concat"), luaL_typename(L, -1), i);
+  luaL_addvalue(b);
+}
+
+
+static int tconcat (lua_State *L) {
+  luaL_Buffer b;
+  size_t lsep;
+  int i, last;
+  const char *sep = luaL_optlstring(L, 2, "", &lsep);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i = luaL_optint(L, 3, 1);
+  last = luaL_opt(L, luaL_checkint, 4, luaL_len(L, 1));
+  luaL_buffinit(L, &b);
+  for (; i < last; i++) {
+    addfield(L, &b, i);
+    luaL_addlstring(&b, sep, lsep);
+  }
+  if (i == last)  /* add last value (if interval was not empty) */
+    addfield(L, &b, i);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** Pack/unpack
+** =======================================================
+*/
+
+static int pack (lua_State *L) {
+  int n = lua_gettop(L);  /* number of elements to pack */
+  lua_createtable(L, n, 1);  /* create result table */
+  lua_pushinteger(L, n);
+  lua_setfield(L, -2, "n");  /* t.n = number of elements */
+  if (n > 0) {  /* at least one element? */
+    int i;
+    lua_pushvalue(L, 1);
+    lua_rawseti(L, -2, 1);  /* insert first element */
+    lua_replace(L, 1);  /* move table into index 1 */
+    for (i = n; i >= 2; i--)  /* assign other elements */
+      lua_rawseti(L, 1, i);
+  }
+  return 1;  /* return table */
+}
+
+
+static int unpack (lua_State *L) {
+  int i, e;
+  unsigned int n;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i = luaL_optint(L, 2, 1);
+  e = luaL_opt(L, luaL_checkint, 3, luaL_len(L, 1));
+  if (i > e) return 0;  /* empty range */
+  n = (unsigned int)e - (unsigned int)i;  /* number of elements minus 1 */
+  if (n > (INT_MAX - 10) || !lua_checkstack(L, ++n))
+    return luaL_error(L, "too many results to unpack");
+  lua_rawgeti(L, 1, i);  /* push arg[i] (avoiding overflow problems) */
+  while (i++ < e)  /* push arg[i + 1...e] */
+    lua_rawgeti(L, 1, i);
+  return n;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Quicksort
+** (based on `Algorithms in MODULA-3', Robert Sedgewick;
+**  Addison-Wesley, 1993.)
+** =======================================================
+*/
+
+
+static void set2 (lua_State *L, int i, int j) {
+  lua_rawseti(L, 1, i);
+  lua_rawseti(L, 1, j);
+}
+
+static int sort_comp (lua_State *L, int a, int b) {
+  if (!lua_isnil(L, 2)) {  /* function? */
+    int res;
+    lua_pushvalue(L, 2);
+    lua_pushvalue(L, a-1);  /* -1 to compensate function */
+    lua_pushvalue(L, b-2);  /* -2 to compensate function and `a' */
+    lua_call(L, 2, 1);
+    res = lua_toboolean(L, -1);
+    lua_pop(L, 1);
+    return res;
+  }
+  else  /* a < b? */
+    return lua_compare(L, a, b, LUA_OPLT);
+}
+
+static void auxsort (lua_State *L, int l, int u) {
+  while (l < u) {  /* for tail recursion */
+    int i, j;
+    /* sort elements a[l], a[(l+u)/2] and a[u] */
+    lua_rawgeti(L, 1, l);
+    lua_rawgeti(L, 1, u);
+    if (sort_comp(L, -1, -2))  /* a[u] < a[l]? */
+      set2(L, l, u);  /* swap a[l] - a[u] */
+    else
+      lua_pop(L, 2);
+    if (u-l == 1) break;  /* only 2 elements */
+    i = (l+u)/2;
+    lua_rawgeti(L, 1, i);
+    lua_rawgeti(L, 1, l);
+    if (sort_comp(L, -2, -1))  /* a[i]<a[l]? */
+      set2(L, i, l);
+    else {
+      lua_pop(L, 1);  /* remove a[l] */
+      lua_rawgeti(L, 1, u);
+      if (sort_comp(L, -1, -2))  /* a[u]<a[i]? */
+        set2(L, i, u);
+      else
+        lua_pop(L, 2);
+    }
+    if (u-l == 2) break;  /* only 3 elements */
+    lua_rawgeti(L, 1, i);  /* Pivot */
+    lua_pushvalue(L, -1);
+    lua_rawgeti(L, 1, u-1);
+    set2(L, i, u-1);
+    /* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */
+    i = l; j = u-1;
+    for (;;) {  /* invariant: a[l..i] <= P <= a[j..u] */
+      /* repeat ++i until a[i] >= P */
+      while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {
+        if (i>=u) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[i] */
+      }
+      /* repeat --j until a[j] <= P */
+      while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {
+        if (j<=l) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[j] */
+      }
+      if (j<i) {
+        lua_pop(L, 3);  /* pop pivot, a[i], a[j] */
+        break;
+      }
+      set2(L, i, j);
+    }
+    lua_rawgeti(L, 1, u-1);
+    lua_rawgeti(L, 1, i);
+    set2(L, u-1, i);  /* swap pivot (a[u-1]) with a[i] */
+    /* a[l..i-1] <= a[i] == P <= a[i+1..u] */
+    /* adjust so that smaller half is in [j..i] and larger one in [l..u] */
+    if (i-l < u-i) {
+      j=l; i=i-1; l=i+2;
+    }
+    else {
+      j=i+1; i=u; u=j-2;
+    }
+    auxsort(L, j, i);  /* call recursively the smaller one */
+  }  /* repeat the routine for the larger one */
+}
+
+static int sort (lua_State *L) {
+  int n = aux_getn(L, 1);
+  luaL_checkstack(L, 40, "");  /* assume array is smaller than 2^40 */
+  if (!lua_isnoneornil(L, 2))  /* is there a 2nd argument? */
+    luaL_checktype(L, 2, LUA_TFUNCTION);
+  lua_settop(L, 2);  /* make sure there is two arguments */
+  auxsort(L, 1, n);
+  return 0;
+}
+
+/* }====================================================== */
+
+
+static const luaL_Reg tab_funcs[] = {
+  {"concat", tconcat},
+#if defined(LUA_COMPAT_MAXN)
+  {"maxn", maxn},
+#endif
+  {"insert", tinsert},
+  {"pack", pack},
+  {"unpack", unpack},
+  {"remove", tremove},
+  {"sort", sort},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_table (lua_State *L) {
+  luaL_newlib(L, tab_funcs);
+#if defined(LUA_COMPAT_UNPACK)
+  /* _G.unpack = table.unpack */
+  lua_getfield(L, -1, "unpack");
+  lua_setglobal(L, "unpack");
+#endif
+  return 1;
+}
+
+#if defined(_KERNEL) && defined(HAVE_SPL)
+
+EXPORT_SYMBOL(luaopen_table);
+
+#endif
+/* END CSTYLED */