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-rw-r--r--Documentation/filesystems/ubifs.txt6
-rw-r--r--fs/ubifs/io.c11
-rw-r--r--fs/ubifs/scan.c2
-rw-r--r--fs/ubifs/super.c34
-rw-r--r--fs/ubifs/tnc.c6
-rw-r--r--fs/ubifs/ubifs.h11
6 files changed, 61 insertions, 9 deletions
diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
index 340512c3250..dd84ea3c10d 100644
--- a/Documentation/filesystems/ubifs.txt
+++ b/Documentation/filesystems/ubifs.txt
@@ -89,6 +89,12 @@ fast_unmount do not commit on unmount; this option makes
bulk_read read more in one go to take advantage of flash
media that read faster sequentially
no_bulk_read (*) do not bulk-read
+no_chk_data_crc skip checking of CRCs on data nodes in order to
+ improve read performance. Use this option only
+ if the flash media is highly reliable. The effect
+ of this option is that corruption of the contents
+ of a file can go unnoticed.
+chk_data_crc (*) do not skip checking CRCs on data nodes
Quick usage instructions
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index 054363f2b20..40e2790b62c 100644
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -74,6 +74,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
* @lnum: logical eraseblock number
* @offs: offset within the logical eraseblock
* @quiet: print no messages
+ * @chk_crc: indicates whether to always check the CRC
*
* This function checks node magic number and CRC checksum. This function also
* validates node length to prevent UBIFS from becoming crazy when an attacker
@@ -85,7 +86,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
* or magic.
*/
int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
- int offs, int quiet)
+ int offs, int quiet, int chk_crc)
{
int err = -EINVAL, type, node_len;
uint32_t crc, node_crc, magic;
@@ -121,6 +122,10 @@ int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
node_len > c->ranges[type].max_len)
goto out_len;
+ if (!chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc)
+ if (c->no_chk_data_crc)
+ return 0;
+
crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
node_crc = le32_to_cpu(ch->crc);
if (crc != node_crc) {
@@ -722,7 +727,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
goto out;
}
- err = ubifs_check_node(c, buf, lnum, offs, 0);
+ err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
if (err) {
ubifs_err("expected node type %d", type);
return err;
@@ -781,7 +786,7 @@ int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
goto out;
}
- err = ubifs_check_node(c, buf, lnum, offs, 0);
+ err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
if (err) {
ubifs_err("expected node type %d", type);
return err;
diff --git a/fs/ubifs/scan.c b/fs/ubifs/scan.c
index acf5c5fffc6..0ed82479b44 100644
--- a/fs/ubifs/scan.c
+++ b/fs/ubifs/scan.c
@@ -87,7 +87,7 @@ int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
dbg_scan("scanning %s", dbg_ntype(ch->node_type));
- if (ubifs_check_node(c, buf, lnum, offs, quiet))
+ if (ubifs_check_node(c, buf, lnum, offs, quiet, 1))
return SCANNED_A_CORRUPT_NODE;
if (ch->node_type == UBIFS_PAD_NODE) {
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index b1c57e8ee85..cf078b5cc88 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -406,6 +406,11 @@ static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
else if (c->mount_opts.bulk_read == 1)
seq_printf(s, ",no_bulk_read");
+ if (c->mount_opts.chk_data_crc == 2)
+ seq_printf(s, ",chk_data_crc");
+ else if (c->mount_opts.chk_data_crc == 1)
+ seq_printf(s, ",no_chk_data_crc");
+
return 0;
}
@@ -859,6 +864,8 @@ static int check_volume_empty(struct ubifs_info *c)
* Opt_norm_unmount: run a journal commit before un-mounting
* Opt_bulk_read: enable bulk-reads
* Opt_no_bulk_read: disable bulk-reads
+ * Opt_chk_data_crc: check CRCs when reading data nodes
+ * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
* Opt_err: just end of array marker
*/
enum {
@@ -866,6 +873,8 @@ enum {
Opt_norm_unmount,
Opt_bulk_read,
Opt_no_bulk_read,
+ Opt_chk_data_crc,
+ Opt_no_chk_data_crc,
Opt_err,
};
@@ -874,6 +883,8 @@ static match_table_t tokens = {
{Opt_norm_unmount, "norm_unmount"},
{Opt_bulk_read, "bulk_read"},
{Opt_no_bulk_read, "no_bulk_read"},
+ {Opt_chk_data_crc, "chk_data_crc"},
+ {Opt_no_chk_data_crc, "no_chk_data_crc"},
{Opt_err, NULL},
};
@@ -919,6 +930,14 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
c->mount_opts.bulk_read = 1;
c->bulk_read = 0;
break;
+ case Opt_chk_data_crc:
+ c->mount_opts.chk_data_crc = 2;
+ c->no_chk_data_crc = 0;
+ break;
+ case Opt_no_chk_data_crc:
+ c->mount_opts.chk_data_crc = 1;
+ c->no_chk_data_crc = 1;
+ break;
default:
ubifs_err("unrecognized mount option \"%s\" "
"or missing value", p);
@@ -1027,6 +1046,8 @@ static int mount_ubifs(struct ubifs_info *c)
goto out_free;
}
+ c->always_chk_crc = 1;
+
err = ubifs_read_superblock(c);
if (err)
goto out_free;
@@ -1168,6 +1189,8 @@ static int mount_ubifs(struct ubifs_info *c)
if (err)
goto out_infos;
+ c->always_chk_crc = 0;
+
ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
c->vi.ubi_num, c->vi.vol_id, c->vi.name);
if (mounted_read_only)
@@ -1313,6 +1336,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
mutex_lock(&c->umount_mutex);
c->remounting_rw = 1;
+ c->always_chk_crc = 1;
/* Check for enough free space */
if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
@@ -1381,13 +1405,15 @@ static int ubifs_remount_rw(struct ubifs_info *c)
c->bgt = NULL;
ubifs_err("cannot spawn \"%s\", error %d",
c->bgt_name, err);
- return err;
+ goto out;
}
wake_up_process(c->bgt);
c->orph_buf = vmalloc(c->leb_size);
- if (!c->orph_buf)
- return -ENOMEM;
+ if (!c->orph_buf) {
+ err = -ENOMEM;
+ goto out;
+ }
/* Check for enough log space */
lnum = c->lhead_lnum + 1;
@@ -1414,6 +1440,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
dbg_gen("re-mounted read-write");
c->vfs_sb->s_flags &= ~MS_RDONLY;
c->remounting_rw = 0;
+ c->always_chk_crc = 0;
mutex_unlock(&c->umount_mutex);
return 0;
@@ -1429,6 +1456,7 @@ out:
c->ileb_buf = NULL;
ubifs_lpt_free(c, 1);
c->remounting_rw = 0;
+ c->always_chk_crc = 0;
mutex_unlock(&c->umount_mutex);
return err;
}
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index d279012d8dd..66dc57100bd 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -470,6 +470,10 @@ static int try_read_node(const struct ubifs_info *c, void *buf, int type,
if (node_len != len)
return 0;
+ if (type == UBIFS_DATA_NODE && !c->always_chk_crc)
+ if (c->no_chk_data_crc)
+ return 0;
+
crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
node_crc = le32_to_cpu(ch->crc);
if (crc != node_crc)
@@ -1687,7 +1691,7 @@ static int validate_data_node(struct ubifs_info *c, void *buf,
goto out_err;
}
- err = ubifs_check_node(c, buf, zbr->lnum, zbr->offs, 0);
+ err = ubifs_check_node(c, buf, zbr->lnum, zbr->offs, 0, 0);
if (err) {
ubifs_err("expected node type %d", UBIFS_DATA_NODE);
goto out;
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 8513239ea8a..d6ae3f7b2b0 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -894,10 +894,12 @@ struct ubifs_orphan {
* struct ubifs_mount_opts - UBIFS-specific mount options information.
* @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
* @bulk_read: enable bulk-reads
+ * @chk_data_crc: check CRCs when reading data nodes
*/
struct ubifs_mount_opts {
unsigned int unmount_mode:2;
unsigned int bulk_read:2;
+ unsigned int chk_data_crc:2;
};
/**
@@ -1001,6 +1003,9 @@ struct ubifs_mount_opts {
* @bulk_read: enable bulk-reads
* @bulk_read_buf_size: buffer size for bulk-reads
*
+ * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
+ * recovery)
+ *
* @dirty_pg_cnt: number of dirty pages (not used)
* @dirty_zn_cnt: number of dirty znodes
* @clean_zn_cnt: number of clean znodes
@@ -1138,6 +1143,7 @@ struct ubifs_mount_opts {
* @rcvrd_mst_node: recovered master node to write when mounting ro to rw
* @size_tree: inode size information for recovery
* @remounting_rw: set while remounting from ro to rw (sb flags have MS_RDONLY)
+ * @always_chk_crc: always check CRCs (while mounting and remounting rw)
* @mount_opts: UBIFS-specific mount options
*
* @dbg_buf: a buffer of LEB size used for debugging purposes
@@ -1244,6 +1250,8 @@ struct ubifs_info {
int bulk_read;
int bulk_read_buf_size;
+ int no_chk_data_crc;
+
atomic_long_t dirty_pg_cnt;
atomic_long_t dirty_zn_cnt;
atomic_long_t clean_zn_cnt;
@@ -1374,6 +1382,7 @@ struct ubifs_info {
struct ubifs_mst_node *rcvrd_mst_node;
struct rb_root size_tree;
int remounting_rw;
+ int always_chk_crc;
struct ubifs_mount_opts mount_opts;
#ifdef CONFIG_UBIFS_FS_DEBUG
@@ -1416,7 +1425,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
int offs, int dtype);
int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
- int offs, int quiet);
+ int offs, int quiet, int chk_crc);
void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
int ubifs_io_init(struct ubifs_info *c);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-21 09:56:03 +0000