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Diffstat (limited to 'ANDROID_3.4.5/drivers/md/dm-flakey.c')
-rw-r--r--ANDROID_3.4.5/drivers/md/dm-flakey.c442
1 files changed, 0 insertions, 442 deletions
diff --git a/ANDROID_3.4.5/drivers/md/dm-flakey.c b/ANDROID_3.4.5/drivers/md/dm-flakey.c
deleted file mode 100644
index ac49c01f..00000000
--- a/ANDROID_3.4.5/drivers/md/dm-flakey.c
+++ /dev/null
@@ -1,442 +0,0 @@
-/*
- * Copyright (C) 2003 Sistina Software (UK) Limited.
- * Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved.
- *
- * This file is released under the GPL.
- */
-
-#include <linux/device-mapper.h>
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/blkdev.h>
-#include <linux/bio.h>
-#include <linux/slab.h>
-
-#define DM_MSG_PREFIX "flakey"
-
-#define all_corrupt_bio_flags_match(bio, fc) \
- (((bio)->bi_rw & (fc)->corrupt_bio_flags) == (fc)->corrupt_bio_flags)
-
-/*
- * Flakey: Used for testing only, simulates intermittent,
- * catastrophic device failure.
- */
-struct flakey_c {
- struct dm_dev *dev;
- unsigned long start_time;
- sector_t start;
- unsigned up_interval;
- unsigned down_interval;
- unsigned long flags;
- unsigned corrupt_bio_byte;
- unsigned corrupt_bio_rw;
- unsigned corrupt_bio_value;
- unsigned corrupt_bio_flags;
-};
-
-enum feature_flag_bits {
- DROP_WRITES
-};
-
-static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
- struct dm_target *ti)
-{
- int r;
- unsigned argc;
- const char *arg_name;
-
- static struct dm_arg _args[] = {
- {0, 6, "Invalid number of feature args"},
- {1, UINT_MAX, "Invalid corrupt bio byte"},
- {0, 255, "Invalid corrupt value to write into bio byte (0-255)"},
- {0, UINT_MAX, "Invalid corrupt bio flags mask"},
- };
-
- /* No feature arguments supplied. */
- if (!as->argc)
- return 0;
-
- r = dm_read_arg_group(_args, as, &argc, &ti->error);
- if (r)
- return r;
-
- while (argc) {
- arg_name = dm_shift_arg(as);
- argc--;
-
- /*
- * drop_writes
- */
- if (!strcasecmp(arg_name, "drop_writes")) {
- if (test_and_set_bit(DROP_WRITES, &fc->flags)) {
- ti->error = "Feature drop_writes duplicated";
- return -EINVAL;
- }
-
- continue;
- }
-
- /*
- * corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>
- */
- if (!strcasecmp(arg_name, "corrupt_bio_byte")) {
- if (!argc) {
- ti->error = "Feature corrupt_bio_byte requires parameters";
- return -EINVAL;
- }
-
- r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error);
- if (r)
- return r;
- argc--;
-
- /*
- * Direction r or w?
- */
- arg_name = dm_shift_arg(as);
- if (!strcasecmp(arg_name, "w"))
- fc->corrupt_bio_rw = WRITE;
- else if (!strcasecmp(arg_name, "r"))
- fc->corrupt_bio_rw = READ;
- else {
- ti->error = "Invalid corrupt bio direction (r or w)";
- return -EINVAL;
- }
- argc--;
-
- /*
- * Value of byte (0-255) to write in place of correct one.
- */
- r = dm_read_arg(_args + 2, as, &fc->corrupt_bio_value, &ti->error);
- if (r)
- return r;
- argc--;
-
- /*
- * Only corrupt bios with these flags set.
- */
- r = dm_read_arg(_args + 3, as, &fc->corrupt_bio_flags, &ti->error);
- if (r)
- return r;
- argc--;
-
- continue;
- }
-
- ti->error = "Unrecognised flakey feature requested";
- return -EINVAL;
- }
-
- if (test_bit(DROP_WRITES, &fc->flags) && (fc->corrupt_bio_rw == WRITE)) {
- ti->error = "drop_writes is incompatible with corrupt_bio_byte with the WRITE flag set";
- return -EINVAL;
- }
-
- return 0;
-}
-
-/*
- * Construct a flakey mapping:
- * <dev_path> <offset> <up interval> <down interval> [<#feature args> [<arg>]*]
- *
- * Feature args:
- * [drop_writes]
- * [corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>]
- *
- * Nth_byte starts from 1 for the first byte.
- * Direction is r for READ or w for WRITE.
- * bio_flags is ignored if 0.
- */
-static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
-{
- static struct dm_arg _args[] = {
- {0, UINT_MAX, "Invalid up interval"},
- {0, UINT_MAX, "Invalid down interval"},
- };
-
- int r;
- struct flakey_c *fc;
- unsigned long long tmpll;
- struct dm_arg_set as;
- const char *devname;
- char dummy;
-
- as.argc = argc;
- as.argv = argv;
-
- if (argc < 4) {
- ti->error = "Invalid argument count";
- return -EINVAL;
- }
-
- fc = kzalloc(sizeof(*fc), GFP_KERNEL);
- if (!fc) {
- ti->error = "Cannot allocate linear context";
- return -ENOMEM;
- }
- fc->start_time = jiffies;
-
- devname = dm_shift_arg(&as);
-
- if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1) {
- ti->error = "Invalid device sector";
- goto bad;
- }
- fc->start = tmpll;
-
- r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error);
- if (r)
- goto bad;
-
- r = dm_read_arg(_args, &as, &fc->down_interval, &ti->error);
- if (r)
- goto bad;
-
- if (!(fc->up_interval + fc->down_interval)) {
- ti->error = "Total (up + down) interval is zero";
- goto bad;
- }
-
- if (fc->up_interval + fc->down_interval < fc->up_interval) {
- ti->error = "Interval overflow";
- goto bad;
- }
-
- r = parse_features(&as, fc, ti);
- if (r)
- goto bad;
-
- if (dm_get_device(ti, devname, dm_table_get_mode(ti->table), &fc->dev)) {
- ti->error = "Device lookup failed";
- goto bad;
- }
-
- ti->num_flush_requests = 1;
- ti->num_discard_requests = 1;
- ti->private = fc;
- return 0;
-
-bad:
- kfree(fc);
- return -EINVAL;
-}
-
-static void flakey_dtr(struct dm_target *ti)
-{
- struct flakey_c *fc = ti->private;
-
- dm_put_device(ti, fc->dev);
- kfree(fc);
-}
-
-static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector)
-{
- struct flakey_c *fc = ti->private;
-
- return fc->start + dm_target_offset(ti, bi_sector);
-}
-
-static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
-{
- struct flakey_c *fc = ti->private;
-
- bio->bi_bdev = fc->dev->bdev;
- if (bio_sectors(bio))
- bio->bi_sector = flakey_map_sector(ti, bio->bi_sector);
-}
-
-static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc)
-{
- unsigned bio_bytes = bio_cur_bytes(bio);
- char *data = bio_data(bio);
-
- /*
- * Overwrite the Nth byte of the data returned.
- */
- if (data && bio_bytes >= fc->corrupt_bio_byte) {
- data[fc->corrupt_bio_byte - 1] = fc->corrupt_bio_value;
-
- DMDEBUG("Corrupting data bio=%p by writing %u to byte %u "
- "(rw=%c bi_rw=%lu bi_sector=%llu cur_bytes=%u)\n",
- bio, fc->corrupt_bio_value, fc->corrupt_bio_byte,
- (bio_data_dir(bio) == WRITE) ? 'w' : 'r',
- bio->bi_rw, (unsigned long long)bio->bi_sector, bio_bytes);
- }
-}
-
-static int flakey_map(struct dm_target *ti, struct bio *bio,
- union map_info *map_context)
-{
- struct flakey_c *fc = ti->private;
- unsigned elapsed;
-
- /* Are we alive ? */
- elapsed = (jiffies - fc->start_time) / HZ;
- if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) {
- /*
- * Flag this bio as submitted while down.
- */
- map_context->ll = 1;
-
- /*
- * Map reads as normal.
- */
- if (bio_data_dir(bio) == READ)
- goto map_bio;
-
- /*
- * Drop writes?
- */
- if (test_bit(DROP_WRITES, &fc->flags)) {
- bio_endio(bio, 0);
- return DM_MAPIO_SUBMITTED;
- }
-
- /*
- * Corrupt matching writes.
- */
- if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == WRITE)) {
- if (all_corrupt_bio_flags_match(bio, fc))
- corrupt_bio_data(bio, fc);
- goto map_bio;
- }
-
- /*
- * By default, error all I/O.
- */
- return -EIO;
- }
-
-map_bio:
- flakey_map_bio(ti, bio);
-
- return DM_MAPIO_REMAPPED;
-}
-
-static int flakey_end_io(struct dm_target *ti, struct bio *bio,
- int error, union map_info *map_context)
-{
- struct flakey_c *fc = ti->private;
- unsigned bio_submitted_while_down = map_context->ll;
-
- /*
- * Corrupt successful READs while in down state.
- * If flags were specified, only corrupt those that match.
- */
- if (fc->corrupt_bio_byte && !error && bio_submitted_while_down &&
- (bio_data_dir(bio) == READ) && (fc->corrupt_bio_rw == READ) &&
- all_corrupt_bio_flags_match(bio, fc))
- corrupt_bio_data(bio, fc);
-
- return error;
-}
-
-static int flakey_status(struct dm_target *ti, status_type_t type,
- char *result, unsigned int maxlen)
-{
- unsigned sz = 0;
- struct flakey_c *fc = ti->private;
- unsigned drop_writes;
-
- switch (type) {
- case STATUSTYPE_INFO:
- result[0] = '\0';
- break;
-
- case STATUSTYPE_TABLE:
- DMEMIT("%s %llu %u %u ", fc->dev->name,
- (unsigned long long)fc->start, fc->up_interval,
- fc->down_interval);
-
- drop_writes = test_bit(DROP_WRITES, &fc->flags);
- DMEMIT("%u ", drop_writes + (fc->corrupt_bio_byte > 0) * 5);
-
- if (drop_writes)
- DMEMIT("drop_writes ");
-
- if (fc->corrupt_bio_byte)
- DMEMIT("corrupt_bio_byte %u %c %u %u ",
- fc->corrupt_bio_byte,
- (fc->corrupt_bio_rw == WRITE) ? 'w' : 'r',
- fc->corrupt_bio_value, fc->corrupt_bio_flags);
-
- break;
- }
- return 0;
-}
-
-static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg)
-{
- struct flakey_c *fc = ti->private;
- struct dm_dev *dev = fc->dev;
- int r = 0;
-
- /*
- * Only pass ioctls through if the device sizes match exactly.
- */
- if (fc->start ||
- ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT)
- r = scsi_verify_blk_ioctl(NULL, cmd);
-
- return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
-}
-
-static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
- struct bio_vec *biovec, int max_size)
-{
- struct flakey_c *fc = ti->private;
- struct request_queue *q = bdev_get_queue(fc->dev->bdev);
-
- if (!q->merge_bvec_fn)
- return max_size;
-
- bvm->bi_bdev = fc->dev->bdev;
- bvm->bi_sector = flakey_map_sector(ti, bvm->bi_sector);
-
- return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
-}
-
-static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
-{
- struct flakey_c *fc = ti->private;
-
- return fn(ti, fc->dev, fc->start, ti->len, data);
-}
-
-static struct target_type flakey_target = {
- .name = "flakey",
- .version = {1, 2, 0},
- .module = THIS_MODULE,
- .ctr = flakey_ctr,
- .dtr = flakey_dtr,
- .map = flakey_map,
- .end_io = flakey_end_io,
- .status = flakey_status,
- .ioctl = flakey_ioctl,
- .merge = flakey_merge,
- .iterate_devices = flakey_iterate_devices,
-};
-
-static int __init dm_flakey_init(void)
-{
- int r = dm_register_target(&flakey_target);
-
- if (r < 0)
- DMERR("register failed %d", r);
-
- return r;
-}
-
-static void __exit dm_flakey_exit(void)
-{
- dm_unregister_target(&flakey_target);
-}
-
-/* Module hooks */
-module_init(dm_flakey_init);
-module_exit(dm_flakey_exit);
-
-MODULE_DESCRIPTION(DM_NAME " flakey target");
-MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
-MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2025-07-08 21:00:11 +0000