diff options
Diffstat (limited to 'arch/powerpc/oprofile/cell/vma_map.c')
-rw-r--r-- | arch/powerpc/oprofile/cell/vma_map.c | 287 |
1 files changed, 287 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 000000000000..76ec1d16aef7 --- /dev/null +++ b/arch/powerpc/oprofile/cell/vma_map.c @@ -0,0 +1,287 @@ +/* + * 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 "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(struct vma_to_fileoffset_map), GFP_KERNEL); + if (!new) { + printk(KERN_ERR "SPU_PROF: %s, line %d: malloc failed\n", + __FUNCTION__, __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; + struct spu_overlay_info ovly; + unsigned int overlay_tbl_offset = -1; + unsigned long phdr_start, 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; + unsigned long ovly_table; + unsigned int n_ovlys; + + /* Get and validate ELF header. */ + + if (copy_from_user(&ehdr, (void *) 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", + __FUNCTION__, __LINE__); + goto fail; + } + if (ehdr.e_machine != EM_SPU) { + printk(KERN_ERR "SPU_PROF: " + "%s, line %d: Unexpected e_machine parsing SPU ELF\n", + __FUNCTION__, __LINE__); + goto fail; + } + if (ehdr.e_type != ET_EXEC) { + printk(KERN_ERR "SPU_PROF: " + "%s, line %d: Unexpected e_type parsing SPU ELF\n", + __FUNCTION__, __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, + (void *) (phdr_start + i * sizeof(phdr)), + 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, + (void *) (shdr_start + i * sizeof(shdr)), + sizeof(shdr))) + goto fail; + + if (shdr.sh_type != SHT_SYMTAB) + continue; + if (shdr.sh_entsize != sizeof (sym)) + continue; + + if (copy_from_user(&shdr_str, + (void *) (shdr_start + shdr.sh_link * + sizeof(shdr)), + 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, (void *) (spu_elf_start + + shdr.sh_offset + j * + sizeof (sym)), + sizeof (sym))) + goto fail; + + if (copy_from_user(name, (void *) + (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 < 0) { + printk(KERN_ERR "SPU_PROF: " + "%s, line %d: Error finding SPU overlay table\n", + __FUNCTION__, __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, (void *) + (ovly_table + i * sizeof (ovly)), + 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; +} |