Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

	drivers/ata/libata-scsi.c
	include/linux/libata.h

Futher merge of Linus's head and compilation fixups.

Signed-Off-By: David Howells <dhowells@redhat.com>

1 files changed, 880 insertions, 0 deletions

diff --git a/arch/powerpc/boot/flatdevtree.c b/arch/powerpc/boot/flatdevtree.c
new file mode 100644
index 000000000000..c76c194715b2
--- /dev/null
+++ b/arch/powerpc/boot/flatdevtree.c
@@ -0,0 +1,880 @@
+/*
+ * 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, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright Pantelis Antoniou 2006
+ * Copyright (C) IBM Corporation 2006
+ *
+ * Authors: Pantelis Antoniou <pantelis@embeddedalley.com>
+ *          Hollis Blanchard <hollisb@us.ibm.com>
+ *          Mark A. Greer <mgreer@mvista.com>
+ *          Paul Mackerras <paulus@samba.org>
+ */
+
+#include <string.h>
+#include <stddef.h>
+#include "flatdevtree.h"
+#include "flatdevtree_env.h"
+
+#define _ALIGN(x, al)   (((x) + (al) - 1) & ~((al) - 1))
+
+/* Routines for keeping node ptrs returned by ft_find_device current */
+/* First entry not used b/c it would return 0 and be taken as NULL/error */
+static void *ft_node_add(struct ft_cxt *cxt, char *node)
+{
+        unsigned int i;
+
+        for (i = 1; i < cxt->nodes_used; i++)   /* already there? */
+                if (cxt->node_tbl[i] == node)
+                        return (void *)i;
+
+        if (cxt->nodes_used < cxt->node_max) {
+                cxt->node_tbl[cxt->nodes_used] = node;
+                return (void *)cxt->nodes_used++;
+        }
+
+        return NULL;
+}
+
+static char *ft_node_ph2node(struct ft_cxt *cxt, const void *phandle)
+{
+        unsigned int i = (unsigned int)phandle;
+
+        if (i < cxt->nodes_used)
+                return cxt->node_tbl[i];
+        return NULL;
+}
+
+static void ft_node_update_before(struct ft_cxt *cxt, char *addr, int shift)
+{
+        unsigned int i;
+
+        if (shift == 0)
+                return;
+
+        for (i = 1; i < cxt->nodes_used; i++)
+                if (cxt->node_tbl[i] < addr)
+                        cxt->node_tbl[i] += shift;
+}
+
+static void ft_node_update_after(struct ft_cxt *cxt, char *addr, int shift)
+{
+        unsigned int i;
+
+        if (shift == 0)
+                return;
+
+        for (i = 1; i < cxt->nodes_used; i++)
+                if (cxt->node_tbl[i] >= addr)
+                        cxt->node_tbl[i] += shift;
+}
+
+/* Struct used to return info from ft_next() */
+struct ft_atom {
+        u32 tag;
+        const char *name;
+        void *data;
+        u32 size;
+};
+
+/* Set ptrs to current one's info; return addr of next one */
+static char *ft_next(struct ft_cxt *cxt, char *p, struct ft_atom *ret)
+{
+        u32 sz;
+
+        if (p >= cxt->rgn[FT_STRUCT].start + cxt->rgn[FT_STRUCT].size)
+                return NULL;
+
+        ret->tag = be32_to_cpu(*(u32 *) p);
+        p += 4;
+
+        switch (ret->tag) {     /* Tag */
+        case OF_DT_BEGIN_NODE:
+                ret->name = p;
+                ret->data = (void *)(p - 4);    /* start of node */
+                p += _ALIGN(strlen(p) + 1, 4);
+                break;
+        case OF_DT_PROP:
+                ret->size = sz = be32_to_cpu(*(u32 *) p);
+                ret->name = cxt->str_anchor + be32_to_cpu(*(u32 *) (p + 4));
+                ret->data = (void *)(p + 8);
+                p += 8 + _ALIGN(sz, 4);
+                break;
+        case OF_DT_END_NODE:
+        case OF_DT_NOP:
+                break;
+        case OF_DT_END:
+        default:
+                p = NULL;
+                break;
+        }
+
+        return p;
+}
+
+#define HDR_SIZE        _ALIGN(sizeof(struct boot_param_header), 8)
+#define EXPAND_INCR     1024    /* alloc this much extra when expanding */
+
+/* See if the regions are in the standard order and non-overlapping */
+static int ft_ordered(struct ft_cxt *cxt)
+{
+        char *p = (char *)cxt->bph + HDR_SIZE;
+        enum ft_rgn_id r;
+
+        for (r = FT_RSVMAP; r <= FT_STRINGS; ++r) {
+                if (p > cxt->rgn[r].start)
+                        return 0;
+                p = cxt->rgn[r].start + cxt->rgn[r].size;
+        }
+        return p <= (char *)cxt->bph + cxt->max_size;
+}
+
+/* Copy the tree to a newly-allocated region and put things in order */
+static int ft_reorder(struct ft_cxt *cxt, int nextra)
+{
+        unsigned long tot;
+        enum ft_rgn_id r;
+        char *p, *pend;
+        int stroff;
+
+        tot = HDR_SIZE + EXPAND_INCR;
+        for (r = FT_RSVMAP; r <= FT_STRINGS; ++r)
+                tot += cxt->rgn[r].size;
+        if (nextra > 0)
+                tot += nextra;
+        tot = _ALIGN(tot, 8);
+
+        if (!cxt->realloc)
+                return 0;
+        p = cxt->realloc(NULL, tot);
+        if (!p)
+                return 0;
+
+        memcpy(p, cxt->bph, sizeof(struct boot_param_header));
+        /* offsets get fixed up later */
+
+        cxt->bph = (struct boot_param_header *)p;
+        cxt->max_size = tot;
+        pend = p + tot;
+        p += HDR_SIZE;
+
+        memcpy(p, cxt->rgn[FT_RSVMAP].start, cxt->rgn[FT_RSVMAP].size);
+        cxt->rgn[FT_RSVMAP].start = p;
+        p += cxt->rgn[FT_RSVMAP].size;
+
+        memcpy(p, cxt->rgn[FT_STRUCT].start, cxt->rgn[FT_STRUCT].size);
+        ft_node_update_after(cxt, cxt->rgn[FT_STRUCT].start,
+                        p - cxt->rgn[FT_STRUCT].start);
+        cxt->p += p - cxt->rgn[FT_STRUCT].start;
+        cxt->rgn[FT_STRUCT].start = p;
+
+        p = pend - cxt->rgn[FT_STRINGS].size;
+        memcpy(p, cxt->rgn[FT_STRINGS].start, cxt->rgn[FT_STRINGS].size);
+        stroff = cxt->str_anchor - cxt->rgn[FT_STRINGS].start;
+        cxt->rgn[FT_STRINGS].start = p;
+        cxt->str_anchor = p + stroff;
+
+        cxt->isordered = 1;
+        return 1;
+}
+
+static inline char *prev_end(struct ft_cxt *cxt, enum ft_rgn_id r)
+{
+        if (r > FT_RSVMAP)
+                return cxt->rgn[r - 1].start + cxt->rgn[r - 1].size;
+        return (char *)cxt->bph + HDR_SIZE;
+}
+
+static inline char *next_start(struct ft_cxt *cxt, enum ft_rgn_id r)
+{
+        if (r < FT_STRINGS)
+                return cxt->rgn[r + 1].start;
+        return (char *)cxt->bph + cxt->max_size;
+}
+
+/*
+ * See if we can expand region rgn by nextra bytes by using up
+ * free space after or before the region.
+ */
+static int ft_shuffle(struct ft_cxt *cxt, char **pp, enum ft_rgn_id rgn,
+                int nextra)
+{
+        char *p = *pp;
+        char *rgn_start, *rgn_end;
+
+        rgn_start = cxt->rgn[rgn].start;
+        rgn_end = rgn_start + cxt->rgn[rgn].size;
+        if (nextra <= 0 || rgn_end + nextra <= next_start(cxt, rgn)) {
+                /* move following stuff */
+                if (p < rgn_end) {
+                        if (nextra < 0)
+                                memmove(p, p - nextra, rgn_end - p + nextra);
+                        else
+                                memmove(p + nextra, p, rgn_end - p);
+                        if (rgn == FT_STRUCT)
+                                ft_node_update_after(cxt, p, nextra);
+                }
+                cxt->rgn[rgn].size += nextra;
+                if (rgn == FT_STRINGS)
+                        /* assumes strings only added at beginning */
+                        cxt->str_anchor += nextra;
+                return 1;
+        }
+        if (prev_end(cxt, rgn) <= rgn_start - nextra) {
+                /* move preceding stuff */
+                if (p > rgn_start) {
+                        memmove(rgn_start - nextra, rgn_start, p - rgn_start);
+                        if (rgn == FT_STRUCT)
+                                ft_node_update_before(cxt, p, -nextra);
+                }
+                *p -= nextra;
+                cxt->rgn[rgn].start -= nextra;
+                cxt->rgn[rgn].size += nextra;
+                return 1;
+        }
+        return 0;
+}
+
+static int ft_make_space(struct ft_cxt *cxt, char **pp, enum ft_rgn_id rgn,
+                         int nextra)
+{
+        unsigned long size, ssize, tot;
+        char *str, *next;
+        enum ft_rgn_id r;
+
+        if (!cxt->isordered && !ft_reorder(cxt, nextra))
+                return 0;
+        if (ft_shuffle(cxt, pp, rgn, nextra))
+                return 1;
+
+        /* See if there is space after the strings section */
+        ssize = cxt->rgn[FT_STRINGS].size;
+        if (cxt->rgn[FT_STRINGS].start + ssize
+                        < (char *)cxt->bph + cxt->max_size) {
+                /* move strings up as far as possible */
+                str = (char *)cxt->bph + cxt->max_size - ssize;
+                cxt->str_anchor += str - cxt->rgn[FT_STRINGS].start;
+                memmove(str, cxt->rgn[FT_STRINGS].start, ssize);
+                cxt->rgn[FT_STRINGS].start = str;
+                /* enough space now? */
+                if (rgn >= FT_STRUCT && ft_shuffle(cxt, pp, rgn, nextra))
+                        return 1;
+        }
+
+        /* how much total free space is there following this region? */
+        tot = 0;
+        for (r = rgn; r < FT_STRINGS; ++r) {
+                char *r_end = cxt->rgn[r].start + cxt->rgn[r].size;
+                tot += next_start(cxt, rgn) - r_end;
+        }
+
+        /* cast is to shut gcc up; we know nextra >= 0 */
+        if (tot < (unsigned int)nextra) {
+                /* have to reallocate */
+                char *newp, *new_start;
+                int shift;
+
+                if (!cxt->realloc)
+                        return 0;
+                size = _ALIGN(cxt->max_size + (nextra - tot) + EXPAND_INCR, 8);
+                newp = cxt->realloc(cxt->bph, size);
+                if (!newp)
+                        return 0;
+                cxt->max_size = size;
+                shift = newp - (char *)cxt->bph;
+
+                if (shift) { /* realloc can return same addr */
+                        cxt->bph = (struct boot_param_header *)newp;
+                        ft_node_update_after(cxt, cxt->rgn[FT_STRUCT].start,
+                                        shift);
+                        for (r = FT_RSVMAP; r <= FT_STRINGS; ++r) {
+                                new_start = cxt->rgn[r].start + shift;
+                                cxt->rgn[r].start = new_start;
+                        }
+                        *pp += shift;
+                        cxt->str_anchor += shift;
+                }
+
+                /* move strings up to the end */
+                str = newp + size - ssize;
+                cxt->str_anchor += str - cxt->rgn[FT_STRINGS].start;
+                memmove(str, cxt->rgn[FT_STRINGS].start, ssize);
+                cxt->rgn[FT_STRINGS].start = str;
+
+                if (ft_shuffle(cxt, pp, rgn, nextra))
+                        return 1;
+        }
+
+        /* must be FT_RSVMAP and we need to move FT_STRUCT up */
+        if (rgn == FT_RSVMAP) {
+                next = cxt->rgn[FT_RSVMAP].start + cxt->rgn[FT_RSVMAP].size
+                        + nextra;
+                ssize = cxt->rgn[FT_STRUCT].size;
+                if (next + ssize >= cxt->rgn[FT_STRINGS].start)
+                        return 0;       /* "can't happen" */
+                memmove(next, cxt->rgn[FT_STRUCT].start, ssize);
+                ft_node_update_after(cxt, cxt->rgn[FT_STRUCT].start, nextra);
+                cxt->rgn[FT_STRUCT].start = next;
+
+                if (ft_shuffle(cxt, pp, rgn, nextra))
+                        return 1;
+        }
+
+        return 0;               /* "can't happen" */
+}
+
+static void ft_put_word(struct ft_cxt *cxt, u32 v)
+{
+        *(u32 *) cxt->p = cpu_to_be32(v);
+        cxt->p += 4;
+}
+
+static void ft_put_bin(struct ft_cxt *cxt, const void *data, unsigned int sz)
+{
+        unsigned long sza = _ALIGN(sz, 4);
+
+        /* zero out the alignment gap if necessary */
+        if (sz < sza)
+                *(u32 *) (cxt->p + sza - 4) = 0;
+
+        /* copy in the data */
+        memcpy(cxt->p, data, sz);
+
+        cxt->p += sza;
+}
+
+int ft_begin_node(struct ft_cxt *cxt, const char *name)
+{
+        unsigned long nlen = strlen(name) + 1;
+        unsigned long len = 8 + _ALIGN(nlen, 4);
+
+        if (!ft_make_space(cxt, &cxt->p, FT_STRUCT, len))
+                return -1;
+        ft_put_word(cxt, OF_DT_BEGIN_NODE);
+        ft_put_bin(cxt, name, strlen(name) + 1);
+        return 0;
+}
+
+void ft_end_node(struct ft_cxt *cxt)
+{
+        ft_put_word(cxt, OF_DT_END_NODE);
+}
+
+void ft_nop(struct ft_cxt *cxt)
+{
+        if (ft_make_space(cxt, &cxt->p, FT_STRUCT, 4))
+                ft_put_word(cxt, OF_DT_NOP);
+}
+
+#define NO_STRING       0x7fffffff
+
+static int lookup_string(struct ft_cxt *cxt, const char *name)
+{
+        char *p, *end;
+
+        p = cxt->rgn[FT_STRINGS].start;
+        end = p + cxt->rgn[FT_STRINGS].size;
+        while (p < end) {
+                if (strcmp(p, (char *)name) == 0)
+                        return p - cxt->str_anchor;
+                p += strlen(p) + 1;
+        }
+
+        return NO_STRING;
+}
+
+/* lookup string and insert if not found */
+static int map_string(struct ft_cxt *cxt, const char *name)
+{
+        int off;
+        char *p;
+
+        off = lookup_string(cxt, name);
+        if (off != NO_STRING)
+                return off;
+        p = cxt->rgn[FT_STRINGS].start;
+        if (!ft_make_space(cxt, &p, FT_STRINGS, strlen(name) + 1))
+                return NO_STRING;
+        strcpy(p, name);
+        return p - cxt->str_anchor;
+}
+
+int ft_prop(struct ft_cxt *cxt, const char *name, const void *data,
+                unsigned int sz)
+{
+        int off, len;
+
+        off = lookup_string(cxt, name);
+        if (off == NO_STRING)
+                return -1;
+
+        len = 12 + _ALIGN(sz, 4);
+        if (!ft_make_space(cxt, &cxt->p, FT_STRUCT, len))
+                return -1;
+
+        ft_put_word(cxt, OF_DT_PROP);
+        ft_put_word(cxt, sz);
+        ft_put_word(cxt, off);
+        ft_put_bin(cxt, data, sz);
+        return 0;
+}
+
+int ft_prop_str(struct ft_cxt *cxt, const char *name, const char *str)
+{
+        return ft_prop(cxt, name, str, strlen(str) + 1);
+}
+
+int ft_prop_int(struct ft_cxt *cxt, const char *name, unsigned int val)
+{
+        u32 v = cpu_to_be32((u32) val);
+
+        return ft_prop(cxt, name, &v, 4);
+}
+
+/* Calculate the size of the reserved map */
+static unsigned long rsvmap_size(struct ft_cxt *cxt)
+{
+        struct ft_reserve *res;
+
+        res = (struct ft_reserve *)cxt->rgn[FT_RSVMAP].start;
+        while (res->start || res->len)
+                ++res;
+        return (char *)(res + 1) - cxt->rgn[FT_RSVMAP].start;
+}
+
+/* Calculate the size of the struct region by stepping through it */
+static unsigned long struct_size(struct ft_cxt *cxt)
+{
+        char *p = cxt->rgn[FT_STRUCT].start;
+        char *next;
+        struct ft_atom atom;
+
+        /* make check in ft_next happy */
+        if (cxt->rgn[FT_STRUCT].size == 0)
+                cxt->rgn[FT_STRUCT].size = 0xfffffffful - (unsigned long)p;
+
+        while ((next = ft_next(cxt, p, &atom)) != NULL)
+                p = next;
+        return p + 4 - cxt->rgn[FT_STRUCT].start;
+}
+
+/* add `adj' on to all string offset values in the struct area */
+static void adjust_string_offsets(struct ft_cxt *cxt, int adj)
+{
+        char *p = cxt->rgn[FT_STRUCT].start;
+        char *next;
+        struct ft_atom atom;
+        int off;
+
+        while ((next = ft_next(cxt, p, &atom)) != NULL) {
+                if (atom.tag == OF_DT_PROP) {
+                        off = be32_to_cpu(*(u32 *) (p + 8));
+                        *(u32 *) (p + 8) = cpu_to_be32(off + adj);
+                }
+                p = next;
+        }
+}
+
+/* start construction of the flat OF tree from scratch */
+void ft_begin(struct ft_cxt *cxt, void *blob, unsigned int max_size,
+                void *(*realloc_fn) (void *, unsigned long))
+{
+        struct boot_param_header *bph = blob;
+        char *p;
+        struct ft_reserve *pres;
+
+        /* clear the cxt */
+        memset(cxt, 0, sizeof(*cxt));
+
+        cxt->bph = bph;
+        cxt->max_size = max_size;
+        cxt->realloc = realloc_fn;
+        cxt->isordered = 1;
+
+        /* zero everything in the header area */
+        memset(bph, 0, sizeof(*bph));
+
+        bph->magic = cpu_to_be32(OF_DT_HEADER);
+        bph->version = cpu_to_be32(0x10);
+        bph->last_comp_version = cpu_to_be32(0x10);
+
+        /* start pointers */
+        cxt->rgn[FT_RSVMAP].start = p = blob + HDR_SIZE;
+        cxt->rgn[FT_RSVMAP].size = sizeof(struct ft_reserve);
+        pres = (struct ft_reserve *)p;
+        cxt->rgn[FT_STRUCT].start = p += sizeof(struct ft_reserve);
+        cxt->rgn[FT_STRUCT].size = 4;
+        cxt->rgn[FT_STRINGS].start = blob + max_size;
+        cxt->rgn[FT_STRINGS].size = 0;
+
+        /* init rsvmap and struct */
+        pres->start = 0;
+        pres->len = 0;
+        *(u32 *) p = cpu_to_be32(OF_DT_END);
+
+        cxt->str_anchor = blob;
+}
+
+/* open up an existing blob to be examined or modified */
+int ft_open(struct ft_cxt *cxt, void *blob, unsigned int max_size,
+                unsigned int max_find_device,
+                void *(*realloc_fn) (void *, unsigned long))
+{
+        struct boot_param_header *bph = blob;
+
+        /* can't cope with version < 16 */
+        if (be32_to_cpu(bph->version) < 16)
+                return -1;
+
+        /* clear the cxt */
+        memset(cxt, 0, sizeof(*cxt));
+
+        /* alloc node_tbl to track node ptrs returned by ft_find_device */
+        ++max_find_device;
+        cxt->node_tbl = realloc_fn(NULL, max_find_device * sizeof(char *));
+        if (!cxt->node_tbl)
+                return -1;
+        memset(cxt->node_tbl, 0, max_find_device * sizeof(char *));
+        cxt->node_max = max_find_device;
+        cxt->nodes_used = 1;    /* don't use idx 0 b/c looks like NULL */
+
+        cxt->bph = bph;
+        cxt->max_size = max_size;
+        cxt->realloc = realloc_fn;
+
+        cxt->rgn[FT_RSVMAP].start = blob + be32_to_cpu(bph->off_mem_rsvmap);
+        cxt->rgn[FT_RSVMAP].size = rsvmap_size(cxt);
+        cxt->rgn[FT_STRUCT].start = blob + be32_to_cpu(bph->off_dt_struct);
+        cxt->rgn[FT_STRUCT].size = struct_size(cxt);
+        cxt->rgn[FT_STRINGS].start = blob + be32_to_cpu(bph->off_dt_strings);
+        cxt->rgn[FT_STRINGS].size = be32_to_cpu(bph->dt_strings_size);
+        /* Leave as '0' to force first ft_make_space call to do a ft_reorder
+         * and move dt to an area allocated by realloc.
+        cxt->isordered = ft_ordered(cxt);
+        */
+
+        cxt->p = cxt->rgn[FT_STRUCT].start;
+        cxt->str_anchor = cxt->rgn[FT_STRINGS].start;
+
+        return 0;
+}
+
+/* add a reserver physical area to the rsvmap */
+int ft_add_rsvmap(struct ft_cxt *cxt, u64 physaddr, u64 size)
+{
+        char *p;
+        struct ft_reserve *pres;
+
+        p = cxt->rgn[FT_RSVMAP].start + cxt->rgn[FT_RSVMAP].size
+                - sizeof(struct ft_reserve);
+        if (!ft_make_space(cxt, &p, FT_RSVMAP, sizeof(struct ft_reserve)))
+                return -1;
+
+        pres = (struct ft_reserve *)p;
+        pres->start = cpu_to_be64(physaddr);
+        pres->len = cpu_to_be64(size);
+
+        return 0;
+}
+
+void ft_begin_tree(struct ft_cxt *cxt)
+{
+        cxt->p = cxt->rgn[FT_STRUCT].start;
+}
+
+void ft_end_tree(struct ft_cxt *cxt)
+{
+        struct boot_param_header *bph = cxt->bph;
+        char *p, *oldstr, *str, *endp;
+        unsigned long ssize;
+        int adj;
+
+        if (!cxt->isordered)
+                return;         /* we haven't touched anything */
+
+        /* adjust string offsets */
+        oldstr = cxt->rgn[FT_STRINGS].start;
+        adj = cxt->str_anchor - oldstr;
+        if (adj)
+                adjust_string_offsets(cxt, adj);
+
+        /* make strings end on 8-byte boundary */
+        ssize = cxt->rgn[FT_STRINGS].size;
+        endp = (char *)_ALIGN((unsigned long)cxt->rgn[FT_STRUCT].start
+                        + cxt->rgn[FT_STRUCT].size + ssize, 8);
+        str = endp - ssize;
+
+        /* move strings down to end of structs */
+        memmove(str, oldstr, ssize);
+        cxt->str_anchor = str;
+        cxt->rgn[FT_STRINGS].start = str;
+
+        /* fill in header fields */
+        p = (char *)bph;
+        bph->totalsize = cpu_to_be32(endp - p);
+        bph->off_mem_rsvmap = cpu_to_be32(cxt->rgn[FT_RSVMAP].start - p);
+        bph->off_dt_struct = cpu_to_be32(cxt->rgn[FT_STRUCT].start - p);
+        bph->off_dt_strings = cpu_to_be32(cxt->rgn[FT_STRINGS].start - p);
+        bph->dt_strings_size = cpu_to_be32(ssize);
+}
+
+void *ft_find_device(struct ft_cxt *cxt, const char *srch_path)
+{
+        char *node;
+
+        /* require absolute path */
+        if (srch_path[0] != '/')
+                return NULL;
+        node = ft_find_descendent(cxt, cxt->rgn[FT_STRUCT].start, srch_path);
+        return ft_node_add(cxt, node);
+}
+
+void *ft_find_descendent(struct ft_cxt *cxt, void *top, const char *srch_path)
+{
+        struct ft_atom atom;
+        char *p;
+        const char *cp, *q;
+        int cl;
+        int depth = -1;
+        int dmatch = 0;
+        const char *path_comp[FT_MAX_DEPTH];
+
+        cp = srch_path;
+        cl = 0;
+        p = top;
+
+        while ((p = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                        ++depth;
+                        if (depth != dmatch)
+                                break;
+                        cxt->genealogy[depth] = atom.data;
+                        cxt->genealogy[depth + 1] = NULL;
+                        if (depth && !(strncmp(atom.name, cp, cl) == 0
+                                        && (atom.name[cl] == '/'
+                                                || atom.name[cl] == '\0'
+                                                || atom.name[cl] == '@')))
+                                break;
+                        path_comp[dmatch] = cp;
+                        /* it matches so far, advance to next path component */
+                        cp += cl;
+                        /* skip slashes */
+                        while (*cp == '/')
+                                ++cp;
+                        /* we're done if this is the end of the string */
+                        if (*cp == 0)
+                                return atom.data;
+                        /* look for end of this component */
+                        q = strchr(cp, '/');
+                        if (q)
+                                cl = q - cp;
+                        else
+                                cl = strlen(cp);
+                        ++dmatch;
+                        break;
+                case OF_DT_END_NODE:
+                        if (depth == 0)
+                                return NULL;
+                        if (dmatch > depth) {
+                                --dmatch;
+                                cl = cp - path_comp[dmatch] - 1;
+                                cp = path_comp[dmatch];
+                                while (cl > 0 && cp[cl - 1] == '/')
+                                        --cl;
+                        }
+                        --depth;
+                        break;
+                }
+        }
+        return NULL;
+}
+
+void *ft_get_parent(struct ft_cxt *cxt, const void *phandle)
+{
+        void *node;
+        int d;
+        struct ft_atom atom;
+        char *p;
+
+        node = ft_node_ph2node(cxt, phandle);
+        if (node == NULL)
+                return NULL;
+
+        for (d = 0; cxt->genealogy[d] != NULL; ++d)
+                if (cxt->genealogy[d] == node)
+                        return cxt->genealogy[d > 0 ? d - 1 : 0];
+
+        /* have to do it the hard way... */
+        p = cxt->rgn[FT_STRUCT].start;
+        d = 0;
+        while ((p = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                        cxt->genealogy[d] = atom.data;
+                        if (node == atom.data) {
+                                /* found it */
+                                cxt->genealogy[d + 1] = NULL;
+                                return d > 0 ? cxt->genealogy[d - 1] : node;
+                        }
+                        ++d;
+                        break;
+                case OF_DT_END_NODE:
+                        --d;
+                        break;
+                }
+        }
+        return NULL;
+}
+
+int ft_get_prop(struct ft_cxt *cxt, const void *phandle, const char *propname,
+                void *buf, const unsigned int buflen)
+{
+        struct ft_atom atom;
+        void *node;
+        char *p;
+        int depth;
+        unsigned int size;
+
+        node = ft_node_ph2node(cxt, phandle);
+        if (node == NULL)
+                return -1;
+
+        depth = 0;
+        p = (char *)node;
+
+        while ((p = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                        ++depth;
+                        break;
+                case OF_DT_PROP:
+                        if ((depth != 1) || strcmp(atom.name, propname))
+                                break;
+                        size = min(atom.size, buflen);
+                        memcpy(buf, atom.data, size);
+                        return atom.size;
+                case OF_DT_END_NODE:
+                        if (--depth <= 0)
+                                return -1;
+                }
+        }
+        return -1;
+}
+
+int ft_set_prop(struct ft_cxt *cxt, const void *phandle, const char *propname,
+                const void *buf, const unsigned int buflen)
+{
+        struct ft_atom atom;
+        void *node;
+        char *p, *next;
+        int nextra, depth;
+
+        node = ft_node_ph2node(cxt, phandle);
+        if (node == NULL)
+                return -1;
+
+        depth = 0;
+        p = node;
+
+        while ((next = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                        ++depth;
+                        break;
+                case OF_DT_END_NODE:
+                        if (--depth > 0)
+                                break;
+                        /* haven't found the property, insert here */
+                        cxt->p = p;
+                        return ft_prop(cxt, propname, buf, buflen);
+                case OF_DT_PROP:
+                        if ((depth != 1) || strcmp(atom.name, propname))
+                                break;
+                        /* found an existing property, overwrite it */
+                        nextra = _ALIGN(buflen, 4) - _ALIGN(atom.size, 4);
+                        cxt->p = atom.data;
+                        if (nextra && !ft_make_space(cxt, &cxt->p, FT_STRUCT,
+                                                nextra))
+                                return -1;
+                        *(u32 *) (cxt->p - 8) = cpu_to_be32(buflen);
+                        ft_put_bin(cxt, buf, buflen);
+                        return 0;
+                }
+                p = next;
+        }
+        return -1;
+}
+
+int ft_del_prop(struct ft_cxt *cxt, const void *phandle, const char *propname)
+{
+        struct ft_atom atom;
+        void *node;
+        char *p, *next;
+        int size;
+
+        node = ft_node_ph2node(cxt, phandle);
+        if (node == NULL)
+                return -1;
+
+        p = node;
+        while ((next = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                case OF_DT_END_NODE:
+                        return -1;
+                case OF_DT_PROP:
+                        if (strcmp(atom.name, propname))
+                                break;
+                        /* found the property, remove it */
+                        size = 12 + -_ALIGN(atom.size, 4);
+                        cxt->p = p;
+                        if (!ft_make_space(cxt, &cxt->p, FT_STRUCT, -size))
+                                return -1;
+                        return 0;
+                }
+                p = next;
+        }
+        return -1;
+}
+
+void *ft_create_node(struct ft_cxt *cxt, const void *parent, const char *path)
+{
+        struct ft_atom atom;
+        char *p, *next;
+        int depth = 0;
+
+        p = cxt->rgn[FT_STRUCT].start;
+        while ((next = ft_next(cxt, p, &atom)) != NULL) {
+                switch (atom.tag) {
+                case OF_DT_BEGIN_NODE:
+                        ++depth;
+                        if (depth == 1 && strcmp(atom.name, path) == 0)
+                                /* duplicate node path, return error */
+                                return NULL;
+                        break;
+                case OF_DT_END_NODE:
+                        --depth;
+                        if (depth > 0)
+                                break;
+                        /* end of node, insert here */
+                        cxt->p = p;
+                        ft_begin_node(cxt, path);
+                        ft_end_node(cxt);
+                        return p;
+                }
+                p = next;
+        }
+        return NULL;
+}