Bulk-read allocates 128KiB or more using kmalloc. The allocation
starts failing often when the memory gets fragmented. UBIFS still
works fine in this case, because it falls-back to standard
(non-optimized) read method, though. This patch teaches bulk-read
to allocate exactly the amount of memory it needs, instead of
allocating 128KiB every time.

This patch is also a preparation to the further fix where we'll
have a pre-allocated bulk-read buffer as well. For example, now
the @bu object is prepared in 'ubifs_bulk_read()', so we could
path either pre-allocated or allocated information to
'ubifs_do_bulk_read()' later. Or teaching 'ubifs_do_bulk_read()'
not to allocate 'bu->buf' if it is already there.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

We print 'ino_t' type using '%lu' printk() placeholder, but this
results in many warnings when compiling for Alpha platform. Fix
this by adding (unsingned long) casts.

Fixes these warnings:

fs/ubifs/journal.c:693: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/journal.c:1131: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/dir.c:163: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/tnc.c:2680: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/tnc.c:2700: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/replay.c:1066: warning: format '%lu' expects type 'long unsigned int', but argument 7 has type 'ino_t'
fs/ubifs/orphan.c:108: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:135: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:142: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:154: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:159: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:451: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:539: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:612: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:843: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/orphan.c:856: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/recovery.c:1438: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/recovery.c:1443: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/recovery.c:1475: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/recovery.c:1495: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:105: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:105: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:110: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:110: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:114: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:114: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:118: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:118: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'ino_t'
fs/ubifs/debug.c:1591: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1671: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1674: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:1680: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1699: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:1788: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:1821: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:1833: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:1924: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1932: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1938: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1945: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1953: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1960: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1967: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1973: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1988: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'ino_t'
fs/ubifs/debug.c:1991: warning: format '%lu' expects type 'long unsigned int', but argument 5 has type 'ino_t'
fs/ubifs/debug.c:2009: warning: format '%lu' expects type 'long unsigned int', but argument 2 has type 'ino_t'
Reported-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

When inserting into a full znode it is split into two
znodes.  Because data node keys are usually consecutive,
it is better to try to keep them together.  This patch
does a better job of that.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

UBIFS read performance can be improved by skipping the CRC
check when data nodes are read.  This option can be used if
the underlying media is considered to be highly reliable.
Note that CRCs are always checked for metadata.

Read speed on Arm platform with OneNAND goes from 19 MiB/s
to 27 MiB/s with data CRC checking disabled.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

Some flash media are capable of reading sequentially at faster rates.
UBIFS bulk-read facility is designed to take advantage of that, by
reading in one go consecutive data nodes that are also located
consecutively in the same LEB.

Read speed on Arm platform with OneNAND goes from 17 MiB/s to
19 MiB/s.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

IS_ERR() macro already has unlikely(), so do not use constructions
like 'if (unlikely(IS_ERR())'.
Signed-off-by: NHirofumi Nakagawa <hnakagawa@miraclelinux.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

- update GC sequence number if any nodes may have been moved
even if GC did not finish the LEB
- don't ignore error return when reading
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The TNC mutex is unlocked prematurely when reading leaf nodes
with non-hashed keys.  This is unsafe because the node may be
moved by garbage collection and the eraseblock unmapped, although
that has never actually happened during stress testing.

This patch fixes the flaw by detecting the race and retrying with
the TNC mutex locked.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

Leaf-nodes that have a hashed key are stored in the
leaf-node-cache (LNC) which is protected by the TNC
mutex.  Consequently, when reading a leaf node with
a hashed key (i.e. directory entries, xattr entries)
the TNC mutex is always required.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.htmlSigned-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>