Re: [PATCH v3 5/7] nvme-pci: add device coredump infrastructure

[Akinobu Mita <akinobu.mita@gmail.com>]

2019年5月14日(火) 0:23 Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>:
>
> On 05/13/2019 12:46 AM, Minwoo Im wrote:
> >> +static int nvme_get_telemetry_log_blocks(struct nvme_ctrl *ctrl, void *buf,
> >> +                                     size_t bytes, loff_t offset)
> >> +{
> >> +    loff_t pos = 0;
> >> +    u32 chunk_size;
> >> +
> >> +    if (check_mul_overflow(ctrl->max_hw_sectors, 512u, &chunk_size))
> >> +            chunk_size = UINT_MAX;
> >> +
> >> +    while (pos < bytes) {
> >> +            size_t size = min_t(size_t, bytes - pos, chunk_size);
> >> +            int ret;
> >> +
> >> +            ret = nvme_get_log(ctrl, NVME_NSID_ALL,
> >> NVME_LOG_TELEMETRY_CTRL,
> >> +                               0, buf + pos, size, offset + pos);
> >> +            if (ret)
> >> +                    return ret;
> >> +
> >> +            pos += size;
> >> +    }
> >> +
> >> +    return 0;
> >> +}
> >> +
> >> +static int nvme_get_telemetry_log(struct nvme_ctrl *ctrl,
> >> +                              struct sg_table *table, size_t bytes)
> >> +{
> >> +    int n = sg_nents(table->sgl);
> >> +    struct scatterlist *sg;
> >> +    size_t offset = 0;
> >> +    int i;
> >> +
> A little comment would be nice if you are using sg operations.
> >> +    for_each_sg(table->sgl, sg, n, i) {
> >> +            struct page *page = sg_page(sg);
> >> +            size_t size = min_t(int, bytes - offset, sg->length);
> >> +            int ret;
> >> +
> >> +            ret = nvme_get_telemetry_log_blocks(ctrl,
> >> page_address(page),
> >> +                                                size, offset);
> >> +            if (ret)
> >> +                    return ret;
> >> +
> >> +            offset += size;
> >> +    }
> >> +
> >> +    return 0;
> >> +}
> >
> > Can we have those two in nvme-core module instead of being in pci module?
>
> Since they are based on the controller they should be moved next to
> nvme_get_log() in the ${KERN_DIR}/drivers/nvme/host/core.c.

OK.  But these functions will be changed to use bio_vec instead of sg in
the next version.