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15 commits

Author SHA1 Message Date
Kumar Gala
6163f5b4c8 malloc: Fix issue with calloc memory possibly being non-zero
Since we set #define MORECORE_CLEARS 1, the code assumes 'sbrk' always
returns zero'd out memory.  However since its possible that free()
returns memory back to sbrk() via malloc_trim we could possible get
non-zero'd memory from sbrk().  This is a problem for when code might
call calloc() and expect the memory to have been zero'd out.

There are two possible solutions to this problem.
1. change #define MORECORE_CLEARS 0
2. memset to zero memory returned to sbrk.

We go with the second since the sbrk being called to free up memory
should be pretty rare.

The following code problems an example test to show the issue.  This
test code was inserted right after the call to mem_malloc_init().

...
       u8 *p2;
       int i;

       printf("MALLOC TEST\n");
       p1 = malloc(135176);
       printf("P1 = %p\n", p1);
       memset(p1, 0xab, 135176);

       free(p1);
       p2 = calloc(4097, 1);
       printf("P2 = %p %p\n", p2, p2 + 4097);

       for (i = 0; i < 4097; i++) {
	       if (p2[i] != 0)
		       printf("miscompare at byte %d got %x\n", i, p2[i]);

       free(p2);
       printf("END MALLOC TEST\n\n");
...

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Tested-by: Wolfgang Denk <wd@denx.de>
2010-11-17 22:06:40 +01:00
Wolfgang Denk
2e5167ccad Replace CONFIG_RELOC_FIXUP_WORKS by CONFIG_NEEDS_MANUAL_RELOC
By now, the majority of architectures have working relocation
support, so the few remaining architectures have become exceptions.
To make this more obvious, we make working relocation now the default
case, and flag the remaining cases with CONFIG_NEEDS_MANUAL_RELOC.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Tested-by: Heiko Schocher <hs@denx.de>
Tested-by: Reinhard Meyer <u-boot@emk-elektronik.de>
2010-10-29 21:32:07 +02:00
Joakim Tjernlund
1ba91ba233 dlmalloc.c: Fix gcc alias warning
Fix these warnings:
dlmalloc.c: In function 'free':
dlmalloc.c:2507: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules
dlmalloc.c:2507: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules
dlmalloc.c:2507: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules

Some page(http://blog.worldofcoding.com/2010/02/solving-gcc-44-strict-aliasing-problems.html)
suggests adding __attribute__((__may_alias__)). Doing so makes the warnings go away.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-10-18 22:44:31 +02:00
Wolfgang Denk
ea882baf9c New implementation for internal handling of environment variables.
Motivation:

* Old environment code used a pessimizing implementation:
  - variable lookup used linear search => slow
  - changed/added variables were added at the end, i. e. most
    frequently used variables had the slowest access times => slow
  - each setenv() would calculate the CRC32 checksum over the whole
    environment block => slow
* "redundant" envrionment was locked down to two copies
* No easy way to implement features like "reset to factory defaults",
  or to select one out of several pre-defined (previously saved) sets
  of environment settings ("profiles")
* No easy way to import or export environment settings

======================================================================

API Changes:

- Variable names starting with '#' are no longer allowed

  I didn't find any such variable names being used; it is highly
  recommended to follow standard conventions and start variable names
  with an alphanumeric character

- "printenv" will now print a backslash at the end of all but the last
  lines of a multi-line variable value.

  Multi-line variables have never been formally defined, allthough
  there is no reason not to use them. Now we define rules how to deal
  with them, allowing for import and export.

- Function forceenv() and the related code in saveenv() was removed.
  At the moment this is causing build problems for the only user of
  this code (schmoogie - which has no entry in MAINTAINERS); may be
  fixed later by implementing the "env set -f" feature.

Inconsistencies:

- "printenv" will '\\'-escape the '\n' in multi-line variables, while
  "printenv var" will not do that.

======================================================================

Advantages:

- "printenv" output much better readable (sorted)
- faster!
- extendable (additional variable properties can be added)
- new, powerful features like "factory reset" or easy switching
  between several different environment settings ("profiles")

Disadvantages:

- Image size grows by typically 5...7 KiB (might shrink a bit again on
  systems with redundant environment with a following patch series)

======================================================================

Implemented:

- env command with subcommands:

  - env print [arg ...]

    same as "printenv": print environment

  - env set [-f] name [arg ...]

    same as "setenv": set (and delete) environment variables

    ["-f" - force setting even for read-only variables - not
    implemented yet.]

  - end delete [-f] name

    not implemented yet

    ["-f" - force delete even for read-only variables]

  - env save

    same as "saveenv": save environment

  - env export [-t | -b | -c] addr [size]

    export internal representation (hash table) in formats usable for
    persistent storage or processing:

	-t:	export as text format; if size is given, data will be
		padded with '\0' bytes; if not, one terminating '\0'
		will be added (which is included in the "filesize"
		setting so you can for exmple copy this to flash and
		keep the termination).
	-b:	export as binary format (name=value pairs separated by
		'\0', list end marked by double "\0\0")
	-c:	export as checksum protected environment format as
		used for example by "saveenv" command
	addr:	memory address where environment gets stored
	size:	size of output buffer

	With "-c" and size is NOT given, then the export command will
	format the data as currently used for the persistent storage,
	i. e. it will use CONFIG_ENV_SECT_SIZE as output block size and
	prepend a valid CRC32 checksum and, in case of resundant
	environment, a "current" redundancy flag. If size is given, this
	value will be used instead of CONFIG_ENV_SECT_SIZE; again, CRC32
	checksum and redundancy flag will be inserted.

	With "-b" and "-t", always only the real data (including a
	terminating '\0' byte) will be written; here the optional size
	argument will be used to make sure not to overflow the user
	provided buffer; the command will abort if the size is not
	sufficient. Any remainign space will be '\0' padded.

        On successful return, the variable "filesize" will be set.
        Note that filesize includes the trailing/terminating '\0'
        byte(s).

        Usage szenario: create a text snapshot/backup of the current
	settings:

		=> env export -t 100000
		=> era ${backup_addr} +${filesize}
		=> cp.b 100000 ${backup_addr} ${filesize}

	Re-import this snapshot, deleting all other settings:

		=> env import -d -t ${backup_addr}

  - env import [-d] [-t | -b | -c] addr [size]

    import external format (text or binary) into hash table,
    optionally deleting existing values:

	-d:	delete existing environment before importing;
		otherwise overwrite / append to existion definitions
	-t:	assume text format; either "size" must be given or the
		text data must be '\0' terminated
	-b:	assume binary format ('\0' separated, "\0\0" terminated)
	-c:	assume checksum protected environment format
	addr:	memory address to read from
	size:	length of input data; if missing, proper '\0'
		termination is mandatory

  - env default -f

    reset default environment: drop all environment settings and load
    default environment

  - env ask name [message] [size]

    same as "askenv": ask for environment variable

  - env edit name

    same as "editenv": edit environment variable

  - env run

    same as "run": run commands in an environment variable

======================================================================

TODO:

- drop default env as implemented now; provide a text file based
  initialization instead (eventually using several text files to
  incrementally build it from common blocks) and a tool to convert it
  into a binary blob / object file.

- It would be nice if we could add wildcard support for environment
  variables; this is needed for variable name auto-completion,
  but it would also be nice to be able to say "printenv ip*" or
  "printenv *addr*"

- Some boards don't link any more due to the grown code size:
  DU405, canyonlands, sequoia, socrates.

	=> cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
	       Stefan Roese <sr@denx.de>,
	       Heiko Schocher <hs@denx.de>

- Dropping forceenv() causes build problems on schmoogie

	=> cc: Sergey Kubushyn <ksi@koi8.net>

- Build tested on PPC and ARM only; runtime tested with NOR and NAND
  flash only => needs testing!!

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
Cc: Stefan Roese <sr@denx.de>,
Cc: Heiko Schocher <hs@denx.de>
Cc: Sergey Kubushyn <ksi@koi8.net>
2010-09-19 19:29:48 +02:00
karl.beldan@gmail.com
ae30b8c200 malloc: sbrk() should return MORECORE_FAILURE instead of NULL on failure
Signed-off-by: Karl Beldan <karl.beldan@gmail.com>
2010-04-10 00:30:27 +02:00
Wolfgang Denk
2740544881 malloc: return NULL if not initialized yet
When malloc() was called before it was properly initialized
(as would happen if when used before relocation to RAM) it returned
random, non-NULL values, which called all kinds of difficult to debug
subsequent errors.

Make sure to return NULL when initialization was not done yet.

Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-01-15 13:26:20 +01:00
Graeme Russ
b4feeb4e8a i386: Fix malloc initialization
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2009-12-05 01:02:10 +01:00
Peter Tyser
521af04d85 Conditionally perform common relocation fixups
Add #ifdefs where necessary to not perform relocation fixups.  This
allows boards/architectures which support relocation to trim a decent
chunk of code.

Note that this patch doesn't add #ifdefs to architecture-specific code
which does not support relocation.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2009-10-03 10:17:57 +02:00
Peter Tyser
d4e8ada0f6 Consolidate arch-specific mem_malloc_init() implementations
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2009-09-04 21:47:07 +02:00
Peter Tyser
5e93bd1c9a Consolidate arch-specific sbrk() implementations
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2009-09-04 21:45:39 +02:00
Stefan Roese
f2302d4430 Fix merge problems
Signed-off-by: Stefan Roese <sr@denx.de>
2008-08-06 14:05:38 +02:00
Kumar Gala
81673e9ae1 Make sure common.h is the first include.
If common.h isn't first we can get CONFIG_ options defined in the
board config file ignored.  This can cause an issue if any of those
config options impact the size of types of data structures
(eg CONFIG_PHYS_64BIT).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-06-03 19:42:05 +02:00
Wolfgang Denk
d87080b721 GCC-4.x fixes: clean up global data pointer initialization for all boards. 2006-03-31 18:32:53 +02:00
wdenk
8bde7f776c * Code cleanup:
- remove trailing white space, trailing empty lines, C++ comments, etc.
  - split cmd_boot.c (separate cmd_bdinfo.c and cmd_load.c)

* Patches by Kenneth Johansson, 25 Jun 2003:
  - major rework of command structure
    (work done mostly by Michal Cendrowski and Joakim Kristiansen)
2003-06-27 21:31:46 +00:00
wdenk
217c9dad82 Initial revision 2002-10-25 20:35:49 +00:00