checks.c

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/*
 * (C) Copyright David Gibson <[email protected]>, IBM Corporation.  2007.
 *
 *
 * 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, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *                                                                   USA
 */

#include "dtc.h"

#ifdef TRACE_CHECKS
#define TRACE(c, ...) \
    do { \
        fprintf(stderr, "=== %s: ", (c)->name); \
        fprintf(stderr, __VA_ARGS__); \
        fprintf(stderr, "\n"); \
    } while (0)
#else
#define TRACE(c, fmt, ...)  do { } while (0)
#endif

enum checkstatus {
    UNCHECKED = 0,
    PREREQ,
    PASSED,
    FAILED,
};

struct check;

typedef void (*tree_check_fn)(struct check *c, struct node *dt);
typedef void (*node_check_fn)(struct check *c, struct node *dt, struct node *node);
typedef void (*prop_check_fn)(struct check *c, struct node *dt,
                  struct node *node, struct property *prop);

struct check {
    const char *name;
    tree_check_fn tree_fn;
    node_check_fn node_fn;
    prop_check_fn prop_fn;
    void *data;
    bool warn, error;
    enum checkstatus status;
    int inprogress;
    int num_prereqs;
    struct check **prereq;
};

#define CHECK_ENTRY(nm, tfn, nfn, pfn, d, w, e, ...)           \
    static struct check *nm##_prereqs[] = { __VA_ARGS__ }; \
    static struct check nm = { \
        .name = #nm, \
        .tree_fn = (tfn), \
        .node_fn = (nfn), \
        .prop_fn = (pfn), \
        .data = (d), \
        .warn = (w), \
        .error = (e), \
        .status = UNCHECKED, \
        .num_prereqs = ARRAY_SIZE(nm##_prereqs), \
        .prereq = nm##_prereqs, \
    };
#define WARNING(nm, tfn, nfn, pfn, d, ...) \
    CHECK_ENTRY(nm, tfn, nfn, pfn, d, true, false, __VA_ARGS__)
#define ERROR(nm, tfn, nfn, pfn, d, ...) \
    CHECK_ENTRY(nm, tfn, nfn, pfn, d, false, true, __VA_ARGS__)
#define CHECK(nm, tfn, nfn, pfn, d, ...) \
    CHECK_ENTRY(nm, tfn, nfn, pfn, d, false, false, __VA_ARGS__)

#define TREE_WARNING(nm, d, ...) \
    WARNING(nm, check_##nm, NULL, NULL, d, __VA_ARGS__)
#define TREE_ERROR(nm, d, ...) \
    ERROR(nm, check_##nm, NULL, NULL, d, __VA_ARGS__)
#define TREE_CHECK(nm, d, ...) \
    CHECK(nm, check_##nm, NULL, NULL, d, __VA_ARGS__)
#define NODE_WARNING(nm, d, ...) \
    WARNING(nm, NULL, check_##nm, NULL, d,  __VA_ARGS__)
#define NODE_ERROR(nm, d, ...) \
    ERROR(nm, NULL, check_##nm, NULL, d, __VA_ARGS__)
#define NODE_CHECK(nm, d, ...) \
    CHECK(nm, NULL, check_##nm, NULL, d, __VA_ARGS__)
#define PROP_WARNING(nm, d, ...) \
    WARNING(nm, NULL, NULL, check_##nm, d, __VA_ARGS__)
#define PROP_ERROR(nm, d, ...) \
    ERROR(nm, NULL, NULL, check_##nm, d, __VA_ARGS__)
#define PROP_CHECK(nm, d, ...) \
    CHECK(nm, NULL, NULL, check_##nm, d, __VA_ARGS__)

#ifdef __GNUC__
static inline void check_msg(struct check *c, const char *fmt, ...) __attribute__((format (printf, 2, 3)));
#endif
static inline void check_msg(struct check *c, const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);

    if ((c->warn && (quiet < 1))
        || (c->error && (quiet < 2))) {
        fprintf(stderr, "%s (%s): ",
            (c->error) ? "ERROR" : "Warning", c->name);
        vfprintf(stderr, fmt, ap);
        fprintf(stderr, "\n");
    }
}

#define FAIL(c, ...) \
    do { \
        TRACE((c), "\t\tFAILED at %s:%d", __FILE__, __LINE__); \
        (c)->status = FAILED; \
        check_msg((c), __VA_ARGS__); \
    } while (0)

static void check_nodes_props(struct check *c, struct node *dt, struct node *node)
{
    struct node *child;
    struct property *prop;

    TRACE(c, "%s", node->fullpath);
    if (c->node_fn)
        c->node_fn(c, dt, node);

    if (c->prop_fn)
        for_each_property(node, prop) {
            TRACE(c, "%s\t'%s'", node->fullpath, prop->name);
            c->prop_fn(c, dt, node, prop);
        }

    for_each_child(node, child)
        check_nodes_props(c, dt, child);
}

static int run_check(struct check *c, struct node *dt)
{
    int error = 0;
    int i;

    assert(!c->inprogress);

    if (c->status != UNCHECKED)
        goto out;

    c->inprogress = 1;

    for (i = 0; i < c->num_prereqs; i++) {
        struct check *prq = c->prereq[i];
        error |= run_check(prq, dt);
        if (prq->status != PASSED) {
            c->status = PREREQ;
            check_msg(c, "Failed prerequisite '%s'",
                  c->prereq[i]->name);
        }
    }

    if (c->status != UNCHECKED)
        goto out;

    if (c->node_fn || c->prop_fn)
        check_nodes_props(c, dt, dt);

    if (c->tree_fn)
        c->tree_fn(c, dt);
    if (c->status == UNCHECKED)
        c->status = PASSED;

    TRACE(c, "\tCompleted, status %d", c->status);

out:
    c->inprogress = 0;
    if ((c->status != PASSED) && (c->error))
        error = 1;
    return error;
}

/*
 * Utility check functions
 */

/* A check which always fails, for testing purposes only */
static inline void check_always_fail(struct check *c, struct node *dt)
{
    FAIL(c, "always_fail check");
}
TREE_CHECK(always_fail, NULL);

static void check_is_string(struct check *c, struct node *root,
                struct node *node)
{
    struct property *prop;
    char *propname = c->data;

    prop = get_property(node, propname);
    if (!prop)
        return; /* Not present, assumed ok */

    if (!data_is_one_string(prop->val))
        FAIL(c, "\"%s\" property in %s is not a string",
             propname, node->fullpath);
}
#define WARNING_IF_NOT_STRING(nm, propname) \
    WARNING(nm, NULL, check_is_string, NULL, (propname))
#define ERROR_IF_NOT_STRING(nm, propname) \
    ERROR(nm, NULL, check_is_string, NULL, (propname))

static void check_is_cell(struct check *c, struct node *root,
              struct node *node)
{
    struct property *prop;
    char *propname = c->data;

    prop = get_property(node, propname);
    if (!prop)
        return; /* Not present, assumed ok */

    if (prop->val.len != sizeof(cell_t))
        FAIL(c, "\"%s\" property in %s is not a single cell",
             propname, node->fullpath);
}
#define WARNING_IF_NOT_CELL(nm, propname) \
    WARNING(nm, NULL, check_is_cell, NULL, (propname))
#define ERROR_IF_NOT_CELL(nm, propname) \
    ERROR(nm, NULL, check_is_cell, NULL, (propname))

/*
 * Structural check functions
 */

static void check_duplicate_node_names(struct check *c, struct node *dt,
                       struct node *node)
{
    struct node *child, *child2;

    for_each_child(node, child)
        for (child2 = child->next_sibling;
             child2;
             child2 = child2->next_sibling)
            if (streq(child->name, child2->name))
                FAIL(c, "Duplicate node name %s",
                     child->fullpath);
}
NODE_ERROR(duplicate_node_names, NULL);

static void check_duplicate_property_names(struct check *c, struct node *dt,
                       struct node *node)
{
    struct property *prop, *prop2;

    for_each_property(node, prop) {
        for (prop2 = prop->next; prop2; prop2 = prop2->next) {
            if (prop2->deleted)
                continue;
            if (streq(prop->name, prop2->name))
                FAIL(c, "Duplicate property name %s in %s",
                     prop->name, node->fullpath);
        }
    }
}
NODE_ERROR(duplicate_property_names, NULL);

#define LOWERCASE   "abcdefghijklmnopqrstuvwxyz"
#define UPPERCASE   "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#define DIGITS      "0123456789"
#define PROPNODECHARS   LOWERCASE UPPERCASE DIGITS ",._+*#?-"

static void check_node_name_chars(struct check *c, struct node *dt,
                  struct node *node)
{
    int n = strspn(node->name, c->data);

    if (n < strlen(node->name))
        FAIL(c, "Bad character '%c' in node %s",
             node->name[n], node->fullpath);
}
NODE_ERROR(node_name_chars, PROPNODECHARS "@");

static void check_node_name_format(struct check *c, struct node *dt,
                   struct node *node)
{
    if (strchr(get_unitname(node), '@'))
        FAIL(c, "Node %s has multiple '@' characters in name",
             node->fullpath);
}
NODE_ERROR(node_name_format, NULL, &node_name_chars);

static void check_property_name_chars(struct check *c, struct node *dt,
                      struct node *node, struct property *prop)
{
    int n = strspn(prop->name, c->data);

    if (n < strlen(prop->name))
        FAIL(c, "Bad character '%c' in property name \"%s\", node %s",
             prop->name[n], prop->name, node->fullpath);
}
PROP_ERROR(property_name_chars, PROPNODECHARS);

#define DESCLABEL_FMT   "%s%s%s%s%s"
#define DESCLABEL_ARGS(node,prop,mark)      \
    ((mark) ? "value of " : ""),        \
    ((prop) ? "'" : ""), \
    ((prop) ? (prop)->name : ""), \
    ((prop) ? "' in " : ""), (node)->fullpath

static void check_duplicate_label(struct check *c, struct node *dt,
                  const char *label, struct node *node,
                  struct property *prop, struct marker *mark)
{
    struct node *othernode = NULL;
    struct property *otherprop = NULL;
    struct marker *othermark = NULL;

    othernode = get_node_by_label(dt, label);

    if (!othernode)
        otherprop = get_property_by_label(dt, label, &othernode);
    if (!othernode)
        othermark = get_marker_label(dt, label, &othernode,
                           &otherprop);

    if (!othernode)
        return;

    if ((othernode != node) || (otherprop != prop) || (othermark != mark))
        FAIL(c, "Duplicate label '%s' on " DESCLABEL_FMT
             " and " DESCLABEL_FMT,
             label, DESCLABEL_ARGS(node, prop, mark),
             DESCLABEL_ARGS(othernode, otherprop, othermark));
}

static void check_duplicate_label_node(struct check *c, struct node *dt,
                       struct node *node)
{
    struct label *l;

    for_each_label(node->labels, l)
        check_duplicate_label(c, dt, l->label, node, NULL, NULL);
}
static void check_duplicate_label_prop(struct check *c, struct node *dt,
                       struct node *node, struct property *prop)
{
    struct marker *m = prop->val.markers;
    struct label *l;

    for_each_label(prop->labels, l)
        check_duplicate_label(c, dt, l->label, node, prop, NULL);

    for_each_marker_of_type(m, LABEL)
        check_duplicate_label(c, dt, m->ref, node, prop, m);
}
ERROR(duplicate_label, NULL, check_duplicate_label_node,
      check_duplicate_label_prop, NULL);

static void check_explicit_phandles(struct check *c, struct node *root,
                    struct node *node, struct property *prop)
{
    struct marker *m;
    struct node *other;
    cell_t phandle;

    if (!streq(prop->name, "phandle")
        && !streq(prop->name, "linux,phandle"))
        return;

    if (prop->val.len != sizeof(cell_t)) {
        FAIL(c, "%s has bad length (%d) %s property",
             node->fullpath, prop->val.len, prop->name);
        return;
    }

    m = prop->val.markers;
    for_each_marker_of_type(m, REF_PHANDLE) {
        assert(m->offset == 0);
        if (node != get_node_by_ref(root, m->ref))
            /* "Set this node's phandle equal to some
             * other node's phandle".  That's nonsensical
             * by construction. */ {
            FAIL(c, "%s in %s is a reference to another node",
                 prop->name, node->fullpath);
            return;
        }
        /* But setting this node's phandle equal to its own
         * phandle is allowed - that means allocate a unique
         * phandle for this node, even if it's not otherwise
         * referenced.  The value will be filled in later, so
         * no further checking for now. */
        return;
    }

    phandle = propval_cell(prop);

    if ((phandle == 0) || (phandle == -1)) {
        FAIL(c, "%s has bad value (0x%x) in %s property",
             node->fullpath, phandle, prop->name);
        return;
    }

    if (node->phandle && (node->phandle != phandle))
        FAIL(c, "%s has %s property which replaces existing phandle information",
             node->fullpath, prop->name);

    other = get_node_by_phandle(root, phandle);
    if (other && (other != node)) {
        FAIL(c, "%s has duplicated phandle 0x%x (seen before at %s)",
             node->fullpath, phandle, other->fullpath);
        return;
    }

    node->phandle = phandle;
}
PROP_ERROR(explicit_phandles, NULL);

static void check_name_properties(struct check *c, struct node *root,
                  struct node *node)
{
    struct property **pp, *prop = NULL;

    for (pp = &node->proplist; *pp; pp = &((*pp)->next))
        if (streq((*pp)->name, "name")) {
            prop = *pp;
            break;
        }

    if (!prop)
        return; /* No name property, that's fine */

    if ((prop->val.len != node->basenamelen+1)
        || (memcmp(prop->val.val, node->name, node->basenamelen) != 0)) {
        FAIL(c, "\"name\" property in %s is incorrect (\"%s\" instead"
             " of base node name)", node->fullpath, prop->val.val);
    } else {
        /* The name property is correct, and therefore redundant.
         * Delete it */
        *pp = prop->next;
        free(prop->name);
        data_free(prop->val);
        free(prop);
    }
}
ERROR_IF_NOT_STRING(name_is_string, "name");
NODE_ERROR(name_properties, NULL, &name_is_string);

/*
 * Reference fixup functions
 */

static void fixup_phandle_references(struct check *c, struct node *dt,
                     struct node *node, struct property *prop)
{
    struct marker *m = prop->val.markers;
    struct node *refnode;
    cell_t phandle;

    for_each_marker_of_type(m, REF_PHANDLE) {
        assert(m->offset + sizeof(cell_t) <= prop->val.len);

        refnode = get_node_by_ref(dt, m->ref);
        if (! refnode) {
            FAIL(c, "Reference to non-existent node or label \"%s\"\n",
                 m->ref);
            continue;
        }

        phandle = get_node_phandle(dt, refnode);
        *((cell_t *)(prop->val.val + m->offset)) = cpu_to_fdt32(phandle);
    }
}
ERROR(phandle_references, NULL, NULL, fixup_phandle_references, NULL,
      &duplicate_node_names, &explicit_phandles);

static void fixup_path_references(struct check *c, struct node *dt,
                  struct node *node, struct property *prop)
{
    struct marker *m = prop->val.markers;
    struct node *refnode;
    char *path;

    for_each_marker_of_type(m, REF_PATH) {
        assert(m->offset <= prop->val.len);

        refnode = get_node_by_ref(dt, m->ref);
        if (!refnode) {
            FAIL(c, "Reference to non-existent node or label \"%s\"\n",
                 m->ref);
            continue;
        }

        path = refnode->fullpath;
        prop->val = data_insert_at_marker(prop->val, m, path,
                          strlen(path) + 1);
    }
}
ERROR(path_references, NULL, NULL, fixup_path_references, NULL,
      &duplicate_node_names);

/*
 * Semantic checks
 */
WARNING_IF_NOT_CELL(address_cells_is_cell, "#address-cells");
WARNING_IF_NOT_CELL(size_cells_is_cell, "#size-cells");
WARNING_IF_NOT_CELL(interrupt_cells_is_cell, "#interrupt-cells");

WARNING_IF_NOT_STRING(device_type_is_string, "device_type");
WARNING_IF_NOT_STRING(model_is_string, "model");
WARNING_IF_NOT_STRING(status_is_string, "status");

static void fixup_addr_size_cells(struct check *c, struct node *dt,
                  struct node *node)
{
    struct property *prop;

    node->addr_cells = -1;
    node->size_cells = -1;

    prop = get_property(node, "#address-cells");
    if (prop)
        node->addr_cells = propval_cell(prop);

    prop = get_property(node, "#size-cells");
    if (prop)
        node->size_cells = propval_cell(prop);
}
WARNING(addr_size_cells, NULL, fixup_addr_size_cells, NULL, NULL,
    &address_cells_is_cell, &size_cells_is_cell);

#define node_addr_cells(n) \
    (((n)->addr_cells == -1) ? 2 : (n)->addr_cells)
#define node_size_cells(n) \
    (((n)->size_cells == -1) ? 1 : (n)->size_cells)

static void check_reg_format(struct check *c, struct node *dt,
                 struct node *node)
{
    struct property *prop;
    int addr_cells, size_cells, entrylen;

    prop = get_property(node, "reg");
    if (!prop)
        return; /* No "reg", that's fine */

    if (!node->parent) {
        FAIL(c, "Root node has a \"reg\" property");
        return;
    }

    if (prop->val.len == 0)
        FAIL(c, "\"reg\" property in %s is empty", node->fullpath);

    addr_cells = node_addr_cells(node->parent);
    size_cells = node_size_cells(node->parent);
    entrylen = (addr_cells + size_cells) * sizeof(cell_t);

    if ((prop->val.len % entrylen) != 0)
        FAIL(c, "\"reg\" property in %s has invalid length (%d bytes) "
             "(#address-cells == %d, #size-cells == %d)",
             node->fullpath, prop->val.len, addr_cells, size_cells);
}
NODE_WARNING(reg_format, NULL, &addr_size_cells);

static void check_ranges_format(struct check *c, struct node *dt,
                struct node *node)
{
    struct property *prop;
    int c_addr_cells, p_addr_cells, c_size_cells, p_size_cells, entrylen;

    prop = get_property(node, "ranges");
    if (!prop)
        return;

    if (!node->parent) {
        FAIL(c, "Root node has a \"ranges\" property");
        return;
    }

    p_addr_cells = node_addr_cells(node->parent);
    p_size_cells = node_size_cells(node->parent);
    c_addr_cells = node_addr_cells(node);
    c_size_cells = node_size_cells(node);
    entrylen = (p_addr_cells + c_addr_cells + c_size_cells) * sizeof(cell_t);

    if (prop->val.len == 0) {
        if (p_addr_cells != c_addr_cells)
            FAIL(c, "%s has empty \"ranges\" property but its "
                 "#address-cells (%d) differs from %s (%d)",
                 node->fullpath, c_addr_cells, node->parent->fullpath,
                 p_addr_cells);
        if (p_size_cells != c_size_cells)
            FAIL(c, "%s has empty \"ranges\" property but its "
                 "#size-cells (%d) differs from %s (%d)",
                 node->fullpath, c_size_cells, node->parent->fullpath,
                 p_size_cells);
    } else if ((prop->val.len % entrylen) != 0) {
        FAIL(c, "\"ranges\" property in %s has invalid length (%d bytes) "
             "(parent #address-cells == %d, child #address-cells == %d, "
             "#size-cells == %d)", node->fullpath, prop->val.len,
             p_addr_cells, c_addr_cells, c_size_cells);
    }
}
NODE_WARNING(ranges_format, NULL, &addr_size_cells);

/*
 * Style checks
 */
static void check_avoid_default_addr_size(struct check *c, struct node *dt,
                      struct node *node)
{
    struct property *reg, *ranges;

    if (!node->parent)
        return; /* Ignore root node */

    reg = get_property(node, "reg");
    ranges = get_property(node, "ranges");

    if (!reg && !ranges)
        return;

    if ((node->parent->addr_cells == -1))
        FAIL(c, "Relying on default #address-cells value for %s",
             node->fullpath);

    if ((node->parent->size_cells == -1))
        FAIL(c, "Relying on default #size-cells value for %s",
             node->fullpath);
}
NODE_WARNING(avoid_default_addr_size, NULL, &addr_size_cells);

static void check_obsolete_chosen_interrupt_controller(struct check *c,
                               struct node *dt)
{
    struct node *chosen;
    struct property *prop;

    chosen = get_node_by_path(dt, "/chosen");
    if (!chosen)
        return;

    prop = get_property(chosen, "interrupt-controller");
    if (prop)
        FAIL(c, "/chosen has obsolete \"interrupt-controller\" "
             "property");
}
TREE_WARNING(obsolete_chosen_interrupt_controller, NULL);

static struct check *check_table[] = {
    &duplicate_node_names, &duplicate_property_names,
    &node_name_chars, &node_name_format, &property_name_chars,
    &name_is_string, &name_properties,

    &duplicate_label,

    &explicit_phandles,
    &phandle_references, &path_references,

    &address_cells_is_cell, &size_cells_is_cell, &interrupt_cells_is_cell,
    &device_type_is_string, &model_is_string, &status_is_string,

    &addr_size_cells, &reg_format, &ranges_format,

    &avoid_default_addr_size,
    &obsolete_chosen_interrupt_controller,

    &always_fail,
};

static void enable_warning_error(struct check *c, bool warn, bool error)
{
    int i;

    /* Raising level, also raise it for prereqs */
    if ((warn && !c->warn) || (error && !c->error))
        for (i = 0; i < c->num_prereqs; i++)
            enable_warning_error(c->prereq[i], warn, error);

    c->warn = c->warn || warn;
    c->error = c->error || error;
}

static void disable_warning_error(struct check *c, bool warn, bool error)
{
    int i;

    /* Lowering level, also lower it for things this is the prereq
     * for */
    if ((warn && c->warn) || (error && c->error)) {
        for (i = 0; i < ARRAY_SIZE(check_table); i++) {
            struct check *cc = check_table[i];
            int j;

            for (j = 0; j < cc->num_prereqs; j++)
                if (cc->prereq[j] == c)
                    disable_warning_error(cc, warn, error);
        }
    }

    c->warn = c->warn && !warn;
    c->error = c->error && !error;
}

void parse_checks_option(bool warn, bool error, const char *optarg)
{
    int i;
    const char *name = optarg;
    bool enable = true;

    if ((strncmp(optarg, "no-", 3) == 0)
        || (strncmp(optarg, "no_", 3) == 0)) {
        name = optarg + 3;
        enable = false;
    }

    for (i = 0; i < ARRAY_SIZE(check_table); i++) {
        struct check *c = check_table[i];

        if (streq(c->name, name)) {
            if (enable)
                enable_warning_error(c, warn, error);
            else
                disable_warning_error(c, warn, error);
            return;
        }
    }

    die("Unrecognized check name \"%s\"\n", name);
}

void process_checks(int force, struct boot_info *bi)
{
    struct node *dt = bi->dt;
    int i;
    int error = 0;

    for (i = 0; i < ARRAY_SIZE(check_table); i++) {
        struct check *c = check_table[i];

        if (c->warn || c->error)
            error = error || run_check(c, dt);
    }

    if (error) {
        if (!force) {
            fprintf(stderr, "ERROR: Input tree has errors, aborting "
                "(use -f to force output)\n");
            exit(2);
        } else if (quiet < 3) {
            fprintf(stderr, "Warning: Input tree has errors, "
                "output forced\n");
        }
    }
}