The goal of summary is to speed up the mount time. Erase block summary (EBS)
stores summary information at the end of every (closed) erase block. It is
no longer necessary to scan all nodes separetly (and read all pages of them)
just read this "small" summary, where every information is stored which is
needed at mount time.

This summary information is stored in a JFFS2_FEATURE_RWCOMPAT_DELETE. During
the mount process if there is no summary info the orignal scan process will
be executed. EBS works with NAND and NOR flashes, too.

There is a user space tool called sumtool to generate this summary
information for a JFFS2 image.
Signed-off-by: NFerenc Havasi <havasi@inf.u-szeged.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Intels Sibley flash needs JFFS2 write buffer functionality
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

JFFS2 uses f->dents to store the pointer to the symlink target string (in case
the inode is symlink). This is somewhat ugly to use the same field for
different reasons. Introduce distinct field f->target for this purpose.
Note, f->fragtree, f->dents, f->target may probably be put in a union.
Signed-off-by: NArtem B. Bityutskiy <dedekind@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NTodd Poynor <tpoynor@mvista.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Fix the bug that caouses problems when compiling for NOR.
We read  a newly erased block so we don't need to check ECC.

Define jffs2_is_writebuffered as zero if there is no wbuf.
Signed-off-by: NArtem B. Bityuckiy <dedekind@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This patch replaces the current CONFIG_JFFS2_FS_NAND, CONFIG_JFFS2_FS_NOR_ECC
and CONFIG_JFFS2_FS_DATAFLASH with a single configuration option -
CONFIG_JFFS2_FS_WRITEBUFFER.

The only functional change of this patch is that the slower div/mod
calculations for SECTOR_ADDR(), PAGE_DIV() and PAGE_MOD() are now always
used when CONFIG_JFFS2_FS_WRITEBUFFER is enabled.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

For Dataflash, can_mark_obsolete = false and the NAND write buffering
code (wbuf.c) is used.

Since the DataFlash chip will automatically erase pages when writing,
the cleanmarkers are not needed - so cleanmarker_oob = false and
cleanmarker_size = 0

DataFlash page-sizes are not a power of two (they're multiples of 528
bytes).  The SECTOR_ADDR macro (added in the previous core patch) is
replaced with a (slower) div/mod version if CONFIG_JFFS2_FS_DATAFLASH is
selected.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

DataFlash page-sizes are not a power of two (they're multiples of 528
bytes).  There are a few places in JFFS2 code where sector_size is used
as a bitmask.  A new macro (SECTOR_ADDR) was defined to calculate these
sector addresses. For non-DataFlash devices, the original (faster)
bitmask operation is still used.

In scan.c, the EMPTY_SCAN_SIZE was a constant of 1024.
Since this could be larger than the sector size of the DataFlash, this
is now basically set to MIN(sector_size, 1024).

Addition of a jffs2_is_writebuffered() macro.
Signed-off-by: NAndrew Victor <andrew@sanpeople.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!