diff options
Diffstat (limited to 'drivers/remoteproc')
| -rw-r--r-- | drivers/remoteproc/remoteproc_coredump.c | 156 |
1 files changed, 138 insertions, 18 deletions
diff --git a/drivers/remoteproc/remoteproc_coredump.c b/drivers/remoteproc/remoteproc_coredump.c index 390f563ec019..bb15a29038e8 100644 --- a/drivers/remoteproc/remoteproc_coredump.c +++ b/drivers/remoteproc/remoteproc_coredump.c @@ -5,6 +5,7 @@ * Copyright (c) 2020, The Linux Foundation. All rights reserved. */ +#include <linux/completion.h> #include <linux/devcoredump.h> #include <linux/device.h> #include <linux/kernel.h> @@ -12,6 +13,12 @@ #include "remoteproc_internal.h" #include "remoteproc_elf_helpers.h" +struct rproc_coredump_state { + struct rproc *rproc; + void *header; + struct completion dump_done; +}; + /** * rproc_coredump_cleanup() - clean up dump_segments list * @rproc: the remote processor handle @@ -115,12 +122,110 @@ int rproc_coredump_set_elf_info(struct rproc *rproc, u8 class, u16 machine) } EXPORT_SYMBOL(rproc_coredump_set_elf_info); +static void rproc_coredump_free(void *data) +{ + struct rproc_coredump_state *dump_state = data; + + vfree(dump_state->header); + complete(&dump_state->dump_done); +} + +static void *rproc_coredump_find_segment(loff_t user_offset, + struct list_head *segments, + size_t *data_left) +{ + struct rproc_dump_segment *segment; + + list_for_each_entry(segment, segments, node) { + if (user_offset < segment->size) { + *data_left = segment->size - user_offset; + return segment; + } + user_offset -= segment->size; + } + + *data_left = 0; + return NULL; +} + +static void rproc_copy_segment(struct rproc *rproc, void *dest, + struct rproc_dump_segment *segment, + size_t offset, size_t size) +{ + void *ptr; + + if (segment->dump) { + segment->dump(rproc, segment, dest, offset, size); + } else { + ptr = rproc_da_to_va(rproc, segment->da + offset, size); + if (!ptr) { + dev_err(&rproc->dev, + "invalid copy request for segment %pad with offset %zu and size %zu)\n", + &segment->da, offset, size); + memset(dest, 0xff, size); + } else { + memcpy(dest, ptr, size); + } + } +} + +static ssize_t rproc_coredump_read(char *buffer, loff_t offset, size_t count, + void *data, size_t header_sz) +{ + size_t seg_data, bytes_left = count; + ssize_t copy_sz; + struct rproc_dump_segment *seg; + struct rproc_coredump_state *dump_state = data; + struct rproc *rproc = dump_state->rproc; + void *elfcore = dump_state->header; + + /* Copy the vmalloc'ed header first. */ + if (offset < header_sz) { + copy_sz = memory_read_from_buffer(buffer, count, &offset, + elfcore, header_sz); + + return copy_sz; + } + + /* + * Find out the segment memory chunk to be copied based on offset. + * Keep copying data until count bytes are read. + */ + while (bytes_left) { + seg = rproc_coredump_find_segment(offset - header_sz, + &rproc->dump_segments, + &seg_data); + /* EOF check */ + if (!seg) { + dev_info(&rproc->dev, "Ramdump done, %lld bytes read", + offset); + break; + } + + copy_sz = min_t(size_t, bytes_left, seg_data); + + rproc_copy_segment(rproc, buffer, seg, seg->size - seg_data, + copy_sz); + + offset += copy_sz; + buffer += copy_sz; + bytes_left -= copy_sz; + } + + return count - bytes_left; +} + /** * rproc_coredump() - perform coredump * @rproc: rproc handle * * This function will generate an ELF header for the registered segments - * and create a devcoredump device associated with rproc. + * and create a devcoredump device associated with rproc. Based on the + * coredump configuration this function will directly copy the segments + * from device memory to userspace or copy segments from device memory to + * a separate buffer, which can then be read by userspace. + * The first approach avoids using extra vmalloc memory. But it will stall + * recovery flow until dump is read by userspace. */ void rproc_coredump(struct rproc *rproc) { @@ -130,11 +235,13 @@ void rproc_coredump(struct rproc *rproc) size_t data_size; size_t offset; void *data; - void *ptr; u8 class = rproc->elf_class; int phnum = 0; + struct rproc_coredump_state dump_state; + enum rproc_dump_mechanism dump_conf = rproc->dump_conf; - if (list_empty(&rproc->dump_segments)) + if (list_empty(&rproc->dump_segments) || + dump_conf == RPROC_COREDUMP_DISABLED) return; if (class == ELFCLASSNONE) { @@ -144,7 +251,14 @@ void rproc_coredump(struct rproc *rproc) data_size = elf_size_of_hdr(class); list_for_each_entry(segment, &rproc->dump_segments, node) { - data_size += elf_size_of_phdr(class) + segment->size; + /* + * For default configuration buffer includes headers & segments. + * For inline dump buffer just includes headers as segments are + * directly read from device memory. + */ + data_size += elf_size_of_phdr(class); + if (dump_conf == RPROC_COREDUMP_DEFAULT) + data_size += segment->size; phnum++; } @@ -183,23 +297,29 @@ void rproc_coredump(struct rproc *rproc) elf_phdr_set_p_flags(class, phdr, PF_R | PF_W | PF_X); elf_phdr_set_p_align(class, phdr, 0); - if (segment->dump) { - segment->dump(rproc, segment, data + offset, 0, segment->size); - } else { - ptr = rproc_da_to_va(rproc, segment->da, segment->size); - if (!ptr) { - dev_err(&rproc->dev, - "invalid coredump segment (%pad, %zu)\n", - &segment->da, segment->size); - memset(data + offset, 0xff, segment->size); - } else { - memcpy(data + offset, ptr, segment->size); - } - } + if (dump_conf == RPROC_COREDUMP_DEFAULT) + rproc_copy_segment(rproc, data + offset, segment, 0, + segment->size); offset += elf_phdr_get_p_filesz(class, phdr); phdr += elf_size_of_phdr(class); } + if (dump_conf == RPROC_COREDUMP_DEFAULT) { + dev_coredumpv(&rproc->dev, data, data_size, GFP_KERNEL); + return; + } + + /* Initialize the dump state struct to be used by rproc_coredump_read */ + dump_state.rproc = rproc; + dump_state.header = data; + init_completion(&dump_state.dump_done); + + dev_coredumpm(&rproc->dev, NULL, &dump_state, data_size, GFP_KERNEL, + rproc_coredump_read, rproc_coredump_free); - dev_coredumpv(&rproc->dev, data, data_size, GFP_KERNEL); + /* + * Wait until the dump is read and free is called. Data is freed + * by devcoredump framework automatically after 5 minutes. + */ + wait_for_completion(&dump_state.dump_done); } |