Hari Bathini <hbathini@xxxxxxxxxxxxx> writes: > diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c > index 2df6f4273ddd..8df085a22fd7 100644 > --- a/arch/powerpc/kexec/file_load_64.c > +++ b/arch/powerpc/kexec/file_load_64.c > @@ -17,9 +17,21 @@ > #include <linux/kexec.h> > #include <linux/of_fdt.h> > #include <linux/libfdt.h> > +#include <linux/of_device.h> > #include <linux/memblock.h> > +#include <linux/slab.h> > +#include <asm/drmem.h> > #include <asm/kexec_ranges.h> > > +struct umem_info { > + uint64_t *buf; /* data buffer for usable-memory property */ > + uint32_t idx; /* current index */ > + uint32_t size; /* size allocated for the data buffer */ Use kernel types please, u64, u32. > + /* usable memory ranges to look up */ > + const struct crash_mem *umrngs; "umrngs". Given it's part of the umem_info struct could it just be "ranges"? > +}; > + > const struct kexec_file_ops * const kexec_file_loaders[] = { > &kexec_elf64_ops, > NULL > @@ -74,6 +86,42 @@ static int get_exclude_memory_ranges(struct crash_mem **mem_ranges) > return ret; > } > > +/** > + * get_usable_memory_ranges - Get usable memory ranges. This list includes > + * regions like crashkernel, opal/rtas & tce-table, > + * that kdump kernel could use. > + * @mem_ranges: Range list to add the memory ranges to. > + * > + * Returns 0 on success, negative errno on error. > + */ > +static int get_usable_memory_ranges(struct crash_mem **mem_ranges) > +{ > + int ret; > + > + /* > + * prom code doesn't take kindly to missing low memory. So, add I don't know what that's referring to, "prom code" is too vague. > + * [0, crashk_res.end] instead of [crashk_res.start, crashk_res.end] > + * to keep it happy. > + */ > + ret = add_mem_range(mem_ranges, 0, crashk_res.end + 1); > + if (ret) > + goto out; > + > + ret = add_rtas_mem_range(mem_ranges); > + if (ret) > + goto out; > + > + ret = add_opal_mem_range(mem_ranges); > + if (ret) > + goto out; > + > + ret = add_tce_mem_ranges(mem_ranges); > +out: > + if (ret) > + pr_err("Failed to setup usable memory ranges\n"); > + return ret; > +} > + > /** > * __locate_mem_hole_top_down - Looks top down for a large enough memory hole > * in the memory regions between buf_min & buf_max > @@ -273,6 +321,382 @@ static int locate_mem_hole_bottom_up_ppc64(struct kexec_buf *kbuf, > return ret; > } > > +/** > + * check_realloc_usable_mem - Reallocate buffer if it can't accommodate entries > + * @um_info: Usable memory buffer and ranges info. > + * @cnt: No. of entries to accommodate. > + * > + * Frees up the old buffer if memory reallocation fails. > + * > + * Returns buffer on success, NULL on error. > + */ > +static uint64_t *check_realloc_usable_mem(struct umem_info *um_info, int cnt) > +{ > + void *tbuf; > + > + if (um_info->size >= > + ((um_info->idx + cnt) * sizeof(*(um_info->buf)))) > + return um_info->buf; This is awkward. AFAICS you only use um_info->size here, so instead why not store the number of u64s you have space for, as num for example. Then the above comparison becomes: if (um_info->num >= (um_info->idx + count)) Then you only have to calculate the size internally here for the realloc. > + > + um_info->size += MEM_RANGE_CHUNK_SZ; new_size = um_info->size + MEM_RANGE_CHUNK_SZ; tbuf = krealloc(um_info->buf, new_size, GFP_KERNEL); > + tbuf = krealloc(um_info->buf, um_info->size, GFP_KERNEL); > + if (!tbuf) { > + um_info->size -= MEM_RANGE_CHUNK_SZ; Then you can drop this. > + return NULL; > + } um_info->size = new_size; > + > + memset(tbuf + um_info->idx, 0, MEM_RANGE_CHUNK_SZ); Just pass __GFP_ZERO to krealloc? > + return tbuf; > +} > + > +/** > + * add_usable_mem - Add the usable memory ranges within the given memory range > + * to the buffer > + * @um_info: Usable memory buffer and ranges info. > + * @base: Base address of memory range to look for. > + * @end: End address of memory range to look for. > + * @cnt: No. of usable memory ranges added to buffer. One caller never uses this AFAICS. Couldn't the other caller just compare the um_info->idx before and after the call, and avoid another pass by reference parameter. > + * > + * Returns 0 on success, negative errno on error. > + */ > +static int add_usable_mem(struct umem_info *um_info, uint64_t base, > + uint64_t end, int *cnt) > +{ > + uint64_t loc_base, loc_end, *buf; > + const struct crash_mem *umrngs; > + int i, add; add should be bool. > + *cnt = 0; > + umrngs = um_info->umrngs; > + for (i = 0; i < umrngs->nr_ranges; i++) { > + add = 0; > + loc_base = umrngs->ranges[i].start; > + loc_end = umrngs->ranges[i].end; > + if (loc_base >= base && loc_end <= end) > + add = 1; > + else if (base < loc_end && end > loc_base) { > + if (loc_base < base) > + loc_base = base; > + if (loc_end > end) > + loc_end = end; > + add = 1; > + } > + > + if (add) { > + buf = check_realloc_usable_mem(um_info, 2); > + if (!buf) > + return -ENOMEM; > + > + um_info->buf = buf; > + buf[um_info->idx++] = cpu_to_be64(loc_base); > + buf[um_info->idx++] = > + cpu_to_be64(loc_end - loc_base + 1); > + (*cnt)++; > + } > + } > + > + return 0; > +} > + > +/** > + * kdump_setup_usable_lmb - This is a callback function that gets called by > + * walk_drmem_lmbs for every LMB to set its > + * usable memory ranges. > + * @lmb: LMB info. > + * @usm: linux,drconf-usable-memory property value. > + * @data: Pointer to usable memory buffer and ranges info. > + * > + * Returns 0 on success, negative errno on error. > + */ > +static int kdump_setup_usable_lmb(struct drmem_lmb *lmb, const __be32 **usm, > + void *data) > +{ > + struct umem_info *um_info; > + uint64_t base, end, *buf; > + int cnt, tmp_idx, ret; > + > + /* > + * kdump load isn't supported on kernels already booted with > + * linux,drconf-usable-memory property. > + */ > + if (*usm) { > + pr_err("linux,drconf-usable-memory property already exists!"); > + return -EINVAL; > + } > + > + um_info = data; > + tmp_idx = um_info->idx; > + buf = check_realloc_usable_mem(um_info, 1); > + if (!buf) > + return -ENOMEM; > + > + um_info->idx++; > + um_info->buf = buf; > + base = lmb->base_addr; > + end = base + drmem_lmb_size() - 1; > + ret = add_usable_mem(um_info, base, end, &cnt); > + if (!ret) > + um_info->buf[tmp_idx] = cpu_to_be64(cnt); > + > + return ret; > +} > + > +/** > + * get_node_path_size - Get the full path length of the given node. > + * @dn: Device Node. > + * > + * Also, counts '\0' at the end of the path. > + * For example, /memory@0 will be "/memory@0\0" => 10 bytes. > + * > + * Returns the string size of the node's full path. > + */ > +static int get_node_path_size(struct device_node *dn) > +{ > + int len = 0; > + > + if (!dn) > + return 0; > + > + /* Root node */ > + if (!(dn->parent)) > + return 2; > + > + while (dn) { > + len += strlen(dn->full_name) + 1; > + dn = dn->parent; > + } > + > + return len; > +} > + > +/** > + * get_node_path - Get the full path of the given node. > + * @node: Device node. > + * > + * Allocates buffer for node path. The caller must free the buffer > + * after use. > + * > + * Returns buffer with path on success, NULL otherwise. > + */ > +static char *get_node_path(struct device_node *node) > +{ As discussed this can probably be replaced with snprintf(buf, "%pOF") ? cheers _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec