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-rw-r--r--arch/powerpc/oprofile/cell/vma_map.c283
1 files changed, 283 insertions, 0 deletions
diff --git a/arch/powerpc/oprofile/cell/vma_map.c b/arch/powerpc/oprofile/cell/vma_map.c
new file mode 100644
index 000000000..f40e37316
--- /dev/null
+++ b/arch/powerpc/oprofile/cell/vma_map.c
@@ -0,0 +1,283 @@
+/*
+ * Cell Broadband Engine OProfile Support
+ *
+ * (C) Copyright IBM Corporation 2006
+ *
+ * Author: Maynard Johnson <maynardj@us.ibm.com>
+ *
+ * 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.
+ */
+
+/* The code in this source file is responsible for generating
+ * vma-to-fileOffset maps for both overlay and non-overlay SPU
+ * applications.
+ */
+
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/elf.h>
+#include <linux/slab.h>
+#include "pr_util.h"
+
+
+void vma_map_free(struct vma_to_fileoffset_map *map)
+{
+ while (map) {
+ struct vma_to_fileoffset_map *next = map->next;
+ kfree(map);
+ map = next;
+ }
+}
+
+unsigned int
+vma_map_lookup(struct vma_to_fileoffset_map *map, unsigned int vma,
+ const struct spu *aSpu, int *grd_val)
+{
+ /*
+ * Default the offset to the physical address + a flag value.
+ * Addresses of dynamically generated code can't be found in the vma
+ * map. For those addresses the flagged value will be sent on to
+ * the user space tools so they can be reported rather than just
+ * thrown away.
+ */
+ u32 offset = 0x10000000 + vma;
+ u32 ovly_grd;
+
+ for (; map; map = map->next) {
+ if (vma < map->vma || vma >= map->vma + map->size)
+ continue;
+
+ if (map->guard_ptr) {
+ ovly_grd = *(u32 *)(aSpu->local_store + map->guard_ptr);
+ if (ovly_grd != map->guard_val)
+ continue;
+ *grd_val = ovly_grd;
+ }
+ offset = vma - map->vma + map->offset;
+ break;
+ }
+
+ return offset;
+}
+
+static struct vma_to_fileoffset_map *
+vma_map_add(struct vma_to_fileoffset_map *map, unsigned int vma,
+ unsigned int size, unsigned int offset, unsigned int guard_ptr,
+ unsigned int guard_val)
+{
+ struct vma_to_fileoffset_map *new = kzalloc(sizeof(*new), GFP_KERNEL);
+
+ if (!new) {
+ printk(KERN_ERR "SPU_PROF: %s, line %d: malloc failed\n",
+ __func__, __LINE__);
+ vma_map_free(map);
+ return NULL;
+ }
+
+ new->next = map;
+ new->vma = vma;
+ new->size = size;
+ new->offset = offset;
+ new->guard_ptr = guard_ptr;
+ new->guard_val = guard_val;
+
+ return new;
+}
+
+
+/* Parse SPE ELF header and generate a list of vma_maps.
+ * A pointer to the first vma_map in the generated list
+ * of vma_maps is returned. */
+struct vma_to_fileoffset_map *create_vma_map(const struct spu *aSpu,
+ unsigned long __spu_elf_start)
+{
+ static const unsigned char expected[EI_PAD] = {
+ [EI_MAG0] = ELFMAG0,
+ [EI_MAG1] = ELFMAG1,
+ [EI_MAG2] = ELFMAG2,
+ [EI_MAG3] = ELFMAG3,
+ [EI_CLASS] = ELFCLASS32,
+ [EI_DATA] = ELFDATA2MSB,
+ [EI_VERSION] = EV_CURRENT,
+ [EI_OSABI] = ELFOSABI_NONE
+ };
+
+ int grd_val;
+ struct vma_to_fileoffset_map *map = NULL;
+ void __user *spu_elf_start = (void __user *)__spu_elf_start;
+ struct spu_overlay_info ovly;
+ unsigned int overlay_tbl_offset = -1;
+ Elf32_Phdr __user *phdr_start;
+ Elf32_Shdr __user *shdr_start;
+ Elf32_Ehdr ehdr;
+ Elf32_Phdr phdr;
+ Elf32_Shdr shdr, shdr_str;
+ Elf32_Sym sym;
+ int i, j;
+ char name[32];
+
+ unsigned int ovly_table_sym = 0;
+ unsigned int ovly_buf_table_sym = 0;
+ unsigned int ovly_table_end_sym = 0;
+ unsigned int ovly_buf_table_end_sym = 0;
+ struct spu_overlay_info __user *ovly_table;
+ unsigned int n_ovlys;
+
+ /* Get and validate ELF header. */
+
+ if (copy_from_user(&ehdr, spu_elf_start, sizeof (ehdr)))
+ goto fail;
+
+ if (memcmp(ehdr.e_ident, expected, EI_PAD) != 0) {
+ printk(KERN_ERR "SPU_PROF: "
+ "%s, line %d: Unexpected e_ident parsing SPU ELF\n",
+ __func__, __LINE__);
+ goto fail;
+ }
+ if (ehdr.e_machine != EM_SPU) {
+ printk(KERN_ERR "SPU_PROF: "
+ "%s, line %d: Unexpected e_machine parsing SPU ELF\n",
+ __func__, __LINE__);
+ goto fail;
+ }
+ if (ehdr.e_type != ET_EXEC) {
+ printk(KERN_ERR "SPU_PROF: "
+ "%s, line %d: Unexpected e_type parsing SPU ELF\n",
+ __func__, __LINE__);
+ goto fail;
+ }
+ phdr_start = spu_elf_start + ehdr.e_phoff;
+ shdr_start = spu_elf_start + ehdr.e_shoff;
+
+ /* Traverse program headers. */
+ for (i = 0; i < ehdr.e_phnum; i++) {
+ if (copy_from_user(&phdr, phdr_start + i, sizeof(phdr)))
+ goto fail;
+
+ if (phdr.p_type != PT_LOAD)
+ continue;
+ if (phdr.p_flags & (1 << 27))
+ continue;
+
+ map = vma_map_add(map, phdr.p_vaddr, phdr.p_memsz,
+ phdr.p_offset, 0, 0);
+ if (!map)
+ goto fail;
+ }
+
+ pr_debug("SPU_PROF: Created non-overlay maps\n");
+ /* Traverse section table and search for overlay-related symbols. */
+ for (i = 0; i < ehdr.e_shnum; i++) {
+ if (copy_from_user(&shdr, shdr_start + i, sizeof(shdr)))
+ goto fail;
+
+ if (shdr.sh_type != SHT_SYMTAB)
+ continue;
+ if (shdr.sh_entsize != sizeof (sym))
+ continue;
+
+ if (copy_from_user(&shdr_str,
+ shdr_start + shdr.sh_link,
+ sizeof(shdr)))
+ goto fail;
+
+ if (shdr_str.sh_type != SHT_STRTAB)
+ goto fail;
+
+ for (j = 0; j < shdr.sh_size / sizeof (sym); j++) {
+ if (copy_from_user(&sym, spu_elf_start +
+ shdr.sh_offset +
+ j * sizeof (sym),
+ sizeof (sym)))
+ goto fail;
+
+ if (copy_from_user(name,
+ spu_elf_start + shdr_str.sh_offset +
+ sym.st_name,
+ 20))
+ goto fail;
+
+ if (memcmp(name, "_ovly_table", 12) == 0)
+ ovly_table_sym = sym.st_value;
+ if (memcmp(name, "_ovly_buf_table", 16) == 0)
+ ovly_buf_table_sym = sym.st_value;
+ if (memcmp(name, "_ovly_table_end", 16) == 0)
+ ovly_table_end_sym = sym.st_value;
+ if (memcmp(name, "_ovly_buf_table_end", 20) == 0)
+ ovly_buf_table_end_sym = sym.st_value;
+ }
+ }
+
+ /* If we don't have overlays, we're done. */
+ if (ovly_table_sym == 0 || ovly_buf_table_sym == 0
+ || ovly_table_end_sym == 0 || ovly_buf_table_end_sym == 0) {
+ pr_debug("SPU_PROF: No overlay table found\n");
+ goto out;
+ } else {
+ pr_debug("SPU_PROF: Overlay table found\n");
+ }
+
+ /* The _ovly_table symbol represents a table with one entry
+ * per overlay section. The _ovly_buf_table symbol represents
+ * a table with one entry per overlay region.
+ * The struct spu_overlay_info gives the structure of the _ovly_table
+ * entries. The structure of _ovly_table_buf is simply one
+ * u32 word per entry.
+ */
+ overlay_tbl_offset = vma_map_lookup(map, ovly_table_sym,
+ aSpu, &grd_val);
+ if (overlay_tbl_offset > 0x10000000) {
+ printk(KERN_ERR "SPU_PROF: "
+ "%s, line %d: Error finding SPU overlay table\n",
+ __func__, __LINE__);
+ goto fail;
+ }
+ ovly_table = spu_elf_start + overlay_tbl_offset;
+
+ n_ovlys = (ovly_table_end_sym -
+ ovly_table_sym) / sizeof (ovly);
+
+ /* Traverse overlay table. */
+ for (i = 0; i < n_ovlys; i++) {
+ if (copy_from_user(&ovly, ovly_table + i, sizeof (ovly)))
+ goto fail;
+
+ /* The ovly.vma/size/offset arguments are analogous to the same
+ * arguments used above for non-overlay maps. The final two
+ * args are referred to as the guard pointer and the guard
+ * value.
+ * The guard pointer is an entry in the _ovly_buf_table,
+ * computed using ovly.buf as the index into the table. Since
+ * ovly.buf values begin at '1' to reference the first (or 0th)
+ * entry in the _ovly_buf_table, the computation subtracts 1
+ * from ovly.buf.
+ * The guard value is stored in the _ovly_buf_table entry and
+ * is an index (starting at 1) back to the _ovly_table entry
+ * that is pointing at this _ovly_buf_table entry. So, for
+ * example, for an overlay scenario with one overlay segment
+ * and two overlay sections:
+ * - Section 1 points to the first entry of the
+ * _ovly_buf_table, which contains a guard value
+ * of '1', referencing the first (index=0) entry of
+ * _ovly_table.
+ * - Section 2 points to the second entry of the
+ * _ovly_buf_table, which contains a guard value
+ * of '2', referencing the second (index=1) entry of
+ * _ovly_table.
+ */
+ map = vma_map_add(map, ovly.vma, ovly.size, ovly.offset,
+ ovly_buf_table_sym + (ovly.buf-1) * 4, i+1);
+ if (!map)
+ goto fail;
+ }
+ goto out;
+
+ fail:
+ map = NULL;
+ out:
+ return map;
+}