diff options
| -rw-r--r-- | drivers/scsi/scsi_debug.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index f2afe757c438..16e4f9626440 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -44,6 +44,7 @@ #include <linux/debugfs.h> #include <linux/async.h> #include <linux/cleanup.h> +#include <linux/parser.h> #include <net/checksum.h> @@ -1168,6 +1169,95 @@ static const struct file_operations sdebug_error_fops = { .release = single_release, }; +enum corrupt_options { + Opt_lba = (1u << 0), + Opt_num = (1u << 1), + Opt_bit_errors = (1u << 2), + Opt_reftag_adjust = (1u << 3), + + Opt_invalid, +}; + +static const match_table_t corrupt_tokens = { + { Opt_lba, "lba=%u" }, + { Opt_num, "num=%u" }, + { Opt_bit_errors, "bit_errors=%u" }, + { Opt_reftag_adjust, "reftag_adjust=%d" }, + { Opt_invalid, NULL, }, +}; + +static int corrupt_lbas(struct sdebug_dev_info *devip, u64 lba, u32 num, + u32 nr_bit_errors, s32 reftag_adjust); +static ssize_t sdebug_corrupt_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct scsi_device *sdev = file->f_inode->i_private; + struct sdebug_dev_info *devip = sdev->hostdata; + substring_t args[MAX_OPT_ARGS]; + char *buf, *options, *p; + int error = 0; + u64 lba = 0; + u32 num = 1; + u32 nr_bit_errors = 0; + s32 reftag_adjust = 0; + + buf = memdup_user_nul(ubuf, count); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + options = buf; + while ((p = strsep(&options, ",\n")) != NULL) { + if (!*p) + continue; + switch (match_token(p, corrupt_tokens, args)) { + case Opt_lba: + error = match_u64(args, &lba); + break; + case Opt_num: + error = match_uint(args, &num); + break; + case Opt_bit_errors: + error = match_uint(args, &nr_bit_errors); + break; + case Opt_reftag_adjust: + error = match_int(args, &reftag_adjust); + break; + default: + pr_warn("unknown parameter or missing value '%s'\n", p); + error = -EINVAL; + } + if (error) + goto out_free_buf; + } + + if (num == 0) { + pr_warn("invalid number of logical blocks: %u\n", num); + error = -EINVAL; + goto out_free_buf; + } + + if (reftag_adjust && + (!sdebug_dix || + (sdebug_dif != T10_PI_TYPE1_PROTECTION && + sdebug_dif != T10_PI_TYPE2_PROTECTION))) { + pr_warn("reftag adjust requires type 1 or type 2 PI with DIX\n"); + error = -EINVAL; + goto out_free_buf; + } + + error = corrupt_lbas(devip, lba, num, nr_bit_errors, reftag_adjust); + +out_free_buf: + kfree(buf); + if (error) + return error; + return count; +} + +static const struct file_operations sdebug_corrupt_fops = { + .write = sdebug_corrupt_write, +}; + static int sdebug_target_reset_fail_show(struct seq_file *m, void *p) { struct scsi_target *starget = (struct scsi_target *)m->private; @@ -4862,6 +4952,82 @@ static int resp_write_tape(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) return 0; } +static int corrupt_lbas(struct sdebug_dev_info *devip, u64 lba, u32 num, + u32 nr_bit_errors, s32 reftag_adjust) +{ + struct sdeb_store_info *sip = devip2sip(devip, false); + bool meta_data_locked = false; + u32 block, num_mapped, b, i; + int error = 0; + + if (sdebug_dev_is_zoned(devip) || + sdebug_dix || + scsi_debug_lbp()) { + sdeb_meta_write_lock(sip); + meta_data_locked = true; + } + + if (!sip) { + pr_err("can't corrupt with fake_rw\n"); + error = -EINVAL; + goto out_unlock; + } + + if (num > sdebug_capacity || lba > sdebug_capacity - num) { + pr_err("logical blocks out of bounds: %llu:%u", lba, num); + error = -EINVAL; + goto out_unlock; + } + + if (scsi_debug_lbp() && + (!map_state(sip, lba, &num_mapped) || num > num_mapped)) { + pr_err("can't modify unmapped logical blocks: %llu:%u", + lba, num); + error = -EINVAL; + goto out_unlock; + } + + /* + * For each possible bit error, flip the same bit in each corrupted + * block to simulate repeated patterns like errors in cables. + */ + sdeb_data_lock(sip, false); + for (b = 0; b < nr_bit_errors; b++) { + unsigned int bit; + + bit = get_random_u32_below(sdebug_sector_size * BITS_PER_BYTE); + pr_info("flipping bit %u in LBAs %llu:%llu\n", + bit, lba, lba + num - 1); + + div_u64_rem(lba, sdebug_store_sectors, &block); + for (i = 0; i < num; i++) { + u8 *p = sip->storep + (block * sdebug_sector_size); + + sdeb_data_sector_lock(sip, true); + p[bit / BITS_PER_BYTE] ^= (1 << (bit % BITS_PER_BYTE)); + sdeb_data_sector_unlock(sip, true); + if (++block >= sdebug_store_sectors) + block = 0; + } + } + + if (reftag_adjust) { + pr_info("adjusting reftag by %d sectors for LBAs %llu:%llu\n", + reftag_adjust, lba, lba + num - 1); + for (i = 0; i < num; i++) { + struct t10_pi_tuple *sdt = dif_store(sip, lba + i); + + be32_add_cpu(&sdt->ref_tag, reftag_adjust); + } + } + sdeb_data_unlock(sip, false); + +out_unlock: + if (meta_data_locked) + sdeb_meta_write_unlock(sip); + return error; +} + static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) { bool check_prot; @@ -6628,6 +6794,8 @@ static int scsi_debug_sdev_configure(struct scsi_device *sdp, if (IS_ERR_OR_NULL(dentry)) pr_info("failed to create error file for device %s\n", dev_name(&sdp->sdev_gendev)); + debugfs_create_file("corrupt", 0600, devip->debugfs_entry, sdp, + &sdebug_corrupt_fops); return 0; } |