Rewrite filesystem code (WIP)

This patch redoes the filesystem code from the FAT driver up to the
clipboard code in onplay.c.

Not every aspect of this is finished therefore it is still "WIP". I
don't wish to do too much at once (haha!). What is left to do is get
dircache back in the sim and find an implementation for the dircache
indicies in the tagcache and playlist code or do something else that
has the same benefit. Leaving these out for now does not make anything
unusable. All the basics are done.

Phone app code should probably get vetted (and app path handling
just plain rewritten as environment expansions); the SDL app and
Android run well.

Main things addressed:
1) Thread safety: There is none right now in the trunk code. Most of
what currently works is luck when multiple threads are involved or
multiple descriptors to the same file are open.

2) POSIX compliance: Many of the functions behave nothing like their
counterparts on a host system. This leads to inconsistent code or very
different behavior from native to hosted. One huge offender was
rename(). Going point by point would fill a book.

3) Actual running RAM usage: Many targets will use less RAM and less
stack space (some more RAM because I upped the number of cache buffers
for large memory). There's very little memory lying fallow in rarely-used
areas (see 'Key core changes' below). Also, all targets may open the same
number of directory streams whereas before those with less than 8MB RAM
were limited to 8, not 12 implying those targets will save slightly
less.

4) Performance: The test_disk plugin shows markedly improved performance,
particularly in the area of (uncached) directory scanning, due partly to
more optimal directory reading and to a better sector cache algorithm.
Uncached times tend to be better while there is a bit of a slowdown in
dircache due to it being a bit heavier of an implementation. It's not
noticeable by a human as far as I can say.

Key core changes:
1) Files and directories share core code and data structures.

2) The filesystem code knows which descriptors refer to same file.
This ensures that changes from one stream are appropriately reflected
in every open descriptor for that file (fileobj_mgr.c).

3) File and directory cache buffers are borrowed from the main sector
cache. This means that when they are not in use by a file, they are not
wasted, but used for the cache. Most of the time, only a few of them
are needed. It also means that adding more file and directory handles
is less expensive. All one must do in ensure a large enough cache to
borrow from.

4) Relative path components are supported and the namespace is unified.
It does not support full relative paths to an implied current directory;
what is does support is use of "." and "..". Adding the former would
not be very difficult. The namespace is unified in the sense that
volumes may be specified several times along with relative parts, e.g.:
"/<0>/foo/../../<1>/bar" :<=> "/<1>/bar".

5) Stack usage is down due to sharing of data, static allocation and
less duplication of strings on the stack. This requires more
serialization than I would like but since the number of threads is
limited to a low number, the tradoff in favor of the stack seems
reasonable.

6) Separates and heirarchicalizes (sic) the SIM and APP filesystem
code. SIM path and volume handling is just like the target. Some
aspects of the APP file code get more straightforward (e.g. no path
hashing is needed).

Dircache:
Deserves its own section. Dircache is new but pays homage to the old.
The old one was not compatible and so it, since it got redone, does
all the stuff it always should have done such as:

1) It may be update and used at any time during the build process.
No longer has one to wait for it to finish building to do basic file
management (create, remove, rename, etc.).

2) It does not need to be either fully scanned or completely disabled;
it can be incomplete (i.e. overfilled, missing paths), still be
of benefit and be correct.

3) Handles mounting and dismounting of individual volumes which means
a full rebuild is not needed just because you pop a new SD card in the
slot. Now, because it reuses its freed entry data, may rebuild only
that volume.

4) Much more fundamental to the file code. When it is built, it is
the keeper of the master file list whether enabled or not ("disabled"
is just a state of the cache). Its must always to ready to be started
and bind all streams opened prior to being enabled.

5) Maintains any short filenames in OEM format which means that it does
not need to be rebuilt when changing the default codepage.

Miscellaneous Compatibility:
1) Update any other code that would otherwise not work such as the
hotswap mounting code in various card drivers.

2) File management: Clipboard needed updating because of the behavioral
changes. Still needs a little more work on some finer points.

3) Remove now-obsolete functionality such as the mutex's "no preempt"
flag (which was only for the prior FAT driver).

4) struct dirinfo uses time_t rather than raw FAT directory entry
time fields. I plan to follow up on genericizing everything there
(i.e. no FAT attributes).

5) unicode.c needed some redoing so that the file code does not try
try to load codepages during a scan, which is actually a problem with
the current code. The default codepage, if any is required, is now
kept in RAM separarately (bufalloced) from codepages specified to
iso_decode() (which must not be bufalloced because the conversion
may be done by playback threads).

Brings with it some additional reusable core code:
1) Revised file functions: Reusable code that does things such as
safe path concatenation and parsing without buffer limitations or
data duplication. Variants that copy or alter the input path may be
based off these.

To do:
1) Put dircache functionality back in the sim. Treating it internally
as a different kind of file system seems the best approach at this
time.

2) Restore use of dircache indexes in the playlist and database or
something effectively the same. Since the cache doesn't have to be
complete in order to be used, not getting a hit on the cache doesn't
unambiguously say if the path exists or not.

Change-Id: Ia30f3082a136253e3a0eae0784e3091d138915c8
Reviewed-on: http://gerrit.rockbox.org/566
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested: Michael Sevakis <jethead71@rockbox.org>

20 files changed, 70 insertions, 51 deletions

diff --git a/bootloader/creativezvm.c b/bootloader/creativezvm.c
index f31f6490a4..6597448193 100644
--- a/bootloader/creativezvm.c
+++ b/bootloader/creativezvm.c
@@ -22,6 +22,7 @@
 #include "../kernel-internal.h"
 #include "storage.h"
 #include "ata-target.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "font.h"
 #include "backlight.h"
@@ -73,6 +74,8 @@ void main(void)
     ret = storage_init();
     if(ret)
         printf("ATA error: %d", ret);
+
+    filesystem_init();
       
     /* If no button is held, start the OF */
     if(button_read_device() == 0)
@@ -93,8 +96,6 @@ void main(void)
     }
     else
     {
-        disk_init();
-
         ret = disk_mount_all();
         if (ret <= 0)
             error(EDISK, ret, true);
diff --git a/bootloader/gigabeat-s.c b/bootloader/gigabeat-s.c
index 3b852dbaa8..499d9c218c 100644
--- a/bootloader/gigabeat-s.c
+++ b/bootloader/gigabeat-s.c
@@ -21,13 +21,16 @@
 #include "config.h"
 #include "system.h"
 #include <stdio.h>
+#include <errno.h>
 #include "../kernel-internal.h"
 #include "gcc_extensions.h"
 #include "string.h"
 #include "adc.h"
 #include "powermgmt.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "dir.h"
+#include "file.h"
 #include "disk.h"
 #include "common.h"
 #include "rb-loader.h"
@@ -219,7 +222,7 @@ static void untar(int tar_fd)
 
             /* Create the dir */
             ret = mkdir(path);
-            if (ret < 0 && ret != -4)
+            if (ret < 0 && errno != EEXIST)
             {
                 printf("failed to create dir (%d)", ret);
             }
@@ -233,14 +236,14 @@ static void handle_untar(void)
     char buf[MAX_PATH];
     char tarstring[6];
     char model[5];
-    struct dirent_uncached* entry;
-    DIR_UNCACHED* dir;
+    struct dirent* entry;
+    DIR* dir;
     int fd;
     int rc;
 
-    dir = opendir_uncached(basedir);
+    dir = opendir(basedir);
 
-    while ((entry = readdir_uncached(dir)))
+    while ((entry = readdir(dir)))
     {
         if (*entry->d_name == '.')
             continue;
@@ -262,7 +265,6 @@ static void handle_untar(void)
                 verbose = true;
                 printf("Found rockbox binary. Moving...");
                 close(fd);
-                remove( BOOTDIR "/" BOOTFILE);
                 int ret = rename(buf, BOOTDIR "/" BOOTFILE);
                 printf("returned %d", ret);
                 sleep(HZ);
@@ -365,7 +367,7 @@ void main(void)
     if(rc)
         error(EATA, rc, true);
 
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc <= 0)
diff --git a/bootloader/gigabeat.c b/bootloader/gigabeat.c
index 52f55a5cdd..4d52407655 100644
--- a/bootloader/gigabeat.c
+++ b/bootloader/gigabeat.c
@@ -30,6 +30,7 @@
 #include "../kernel-internal.h"
 #include "storage.h"
 #include "fat.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "font.h"
 #include "adc.h"
@@ -185,7 +186,7 @@ void main(void)
         error(EATA, rc, true);
     }
 
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc<=0)
diff --git a/bootloader/iaudio_coldfire.c b/bootloader/iaudio_coldfire.c
index 013e8859e8..2f31958a87 100644
--- a/bootloader/iaudio_coldfire.c
+++ b/bootloader/iaudio_coldfire.c
@@ -196,7 +196,7 @@ void main(void)
     if(rc)
         error(EATA, rc, true);
 
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc<=0)
diff --git a/bootloader/imx233.c b/bootloader/imx233.c
index d2562d0676..76fdf884da 100644
--- a/bootloader/imx233.c
+++ b/bootloader/imx233.c
@@ -35,6 +35,7 @@
 #include "rb-loader.h"
 #include "loader_strerror.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "panic.h"
 #include "power.h"
@@ -171,7 +172,7 @@ void main(uint32_t arg, uint32_t addr)
     if(ret < 0)
         error(EATA, ret, true);
 
-    disk_init_subsystem();
+    filesystem_init();
 
     /* NOTE: disk_mount_all to fail since we can do USB after.
      * We need this order to determine the correct logical sector size */
diff --git a/bootloader/ipod.c b/bootloader/ipod.c
index b2d4532168..8580886ce4 100644
--- a/bootloader/ipod.c
+++ b/bootloader/ipod.c
@@ -33,6 +33,7 @@
 #include "../kernel-internal.h"
 #include "ata.h"
 #include "fat.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "font.h"
 #include "adc.h"
@@ -295,7 +296,7 @@ void* main(void)
     int rc;
     bool haveramos;
     bool button_was_held;
-    struct partinfo* pinfo;
+    struct partinfo pinfo;
     unsigned short* identify_info;
 
     /* Check the button hold status as soon as possible - to 
@@ -353,7 +354,8 @@ void* main(void)
       printf("ATA: %d", i);
     }
 
-    disk_init();
+    filesystem_init();
+
     rc = disk_mount_all();
     if (rc<=0)
     {
@@ -361,9 +363,9 @@ void* main(void)
         fatal_error();
     }
 
-    pinfo = disk_partinfo(1);
+    disk_partinfo(1, &pinfo);
     printf("Partition 1: 0x%02x %ld sectors", 
-           pinfo->type, pinfo->size);
+           pinfo.type, pinfo.size);
 
     if (button_was_held || (btn==BUTTON_MENU)) {
         /* If either the hold switch was on, or the Menu button was held, then 
diff --git a/bootloader/ipodnano2g.c b/bootloader/ipodnano2g.c
index cdd866f71e..d0a8e0206c 100644
--- a/bootloader/ipodnano2g.c
+++ b/bootloader/ipodnano2g.c
@@ -32,6 +32,7 @@
 #include "lcd.h"
 #include "i2c-s5l8700.h"
 #include "../kernel-internal.h"
+#include "file_internal.h"
 #include "storage.h"
 #include "fat.h"
 #include "disk.h"
@@ -213,7 +214,8 @@ void main(void)
         fatal_error();
     }
 
-    disk_init();
+    filesystem_init();
+
     rc = disk_mount_all();
     if (rc<=0)
     {
diff --git a/bootloader/iriver_h1x0.c b/bootloader/iriver_h1x0.c
index 7f236d4510..742d0dd254 100644
--- a/bootloader/iriver_h1x0.c
+++ b/bootloader/iriver_h1x0.c
@@ -31,6 +31,7 @@
 #include "scroll_engine.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "usb.h"
 #include "disk.h"
 #include "font.h"
@@ -596,7 +597,7 @@ void main(void)
     }
 
 
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc<=0)
diff --git a/bootloader/iriver_h300.c b/bootloader/iriver_h300.c
index 362eb947c8..100e660a67 100644
--- a/bootloader/iriver_h300.c
+++ b/bootloader/iriver_h300.c
@@ -31,6 +31,7 @@
 #include "scroll_engine.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "usb.h"
 #include "disk.h"
 #include "font.h"
@@ -349,8 +350,7 @@ void main(void)
         while(!(button_get(true) & BUTTON_REL));
     }
 
-
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc<=0)
diff --git a/bootloader/main-e200r-installer.c b/bootloader/main-e200r-installer.c
index 490f1f04dd..c5751d3095 100644
--- a/bootloader/main-e200r-installer.c
+++ b/bootloader/main-e200r-installer.c
@@ -26,12 +26,13 @@
 #include <stdlib.h>
 #include "common.h"
 #include "cpu.h"
-#include "file.h"
 #include "system.h"
 #include "../kernel-internal.h"
 #include "lcd.h"
 #include "font.h"
 #include "storage.h"
+#include "file_internal.h"
+#include "file.h"
 #include "button.h"
 #include "disk.h"
 #include "crc32-mi4.h"
@@ -92,7 +93,7 @@ void* main(void)
     int num_partitions;
     int crc32;
     char sector[512];
-    struct partinfo* pinfo;
+    struct partinfo pinfo;
 
     system_init();
     kernel_init();
@@ -117,7 +118,7 @@ void* main(void)
     printf("");
 
     i=storage_init();
-    disk_init(IF_MV(0));
+    filesystem_init();
     num_partitions = disk_mount_all();
 
     if (num_partitions<=0)
@@ -125,17 +126,17 @@ void* main(void)
         error(EDISK, num_partitions, true);
     }
 
-    pinfo = disk_partinfo(1);
+    disk_partinfo(1, &pinfo);
 
 #if 0 /* not needed in release builds */
     printf("--- Partition info ---");
-    printf("start: %x", pinfo->start);
-    printf("size: %x", pinfo->size);
-    printf("type: %x", pinfo->type);
+    printf("start: %x", pinfo.start);
+    printf("size: %x", pinfo.size);
+    printf("type: %x", pinfo.type);
     printf("reading: %x", (START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK)*512);
 #endif
 
-    storage_read_sectors(pinfo->start + START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK,
+    storage_read_sectors(pinfo.start + START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK,
                          1 , sector);
     crc32 = chksum_crc32 (sector, 512);
 
@@ -157,7 +158,7 @@ void* main(void)
         memcpy(&sector[HACK_OFFSET], changedBytes,
                 sizeof(changedBytes)/sizeof(*changedBytes));
         storage_write_sectors(
-                        pinfo->start + START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK,
+                        pinfo.start + START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK,
                         1 , sector);
         printf("Firmware unlocked");
         printf("Proceed to Step 2");
diff --git a/bootloader/main-pp.c b/bootloader/main-pp.c
index 38760a0e58..562cf17ca4 100644
--- a/bootloader/main-pp.c
+++ b/bootloader/main-pp.c
@@ -33,6 +33,7 @@
 #include "lcd.h"
 #include "font.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "adc.h"
 #include "button.h"
 #include "disk.h"
@@ -291,7 +292,7 @@ void* main(void)
     int btn;
     int rc;
     int num_partitions;
-    struct partinfo* pinfo;
+    struct partinfo pinfo;
 #if !(CONFIG_STORAGE & STORAGE_SD)
     char buf[256];
     unsigned short* identify_info;
@@ -370,7 +371,7 @@ void* main(void)
     }
 #endif
 
-    disk_init(IF_MV(0));
+    filesystem_init();
     num_partitions = disk_mount_all();
     if (num_partitions<=0)
     {
@@ -381,9 +382,9 @@ void* main(void)
        that have more than that */
     for(i=0; i<NUM_PARTITIONS; i++)
     {
-        pinfo = disk_partinfo(i);
+        disk_partinfo(i, &pinfo);
         printf("Partition %d: 0x%02x %ld MB",
-                i, pinfo->type, pinfo->size / 2048);
+                i, pinfo.type, pinfo.size / 2048);
     }
 
     /* Now that storage is initialized, check for USB connection */
@@ -430,10 +431,10 @@ void* main(void)
 #if (CONFIG_STORAGE & STORAGE_SD)
         /* First try a (hidden) firmware partition */
         printf("Trying firmware partition");
-        pinfo = disk_partinfo(1);
-        if(pinfo->type == PARTITION_TYPE_OS2_HIDDEN_C_DRIVE)
+        disk_partinfo(1, &pinfo);
+        if(pinfo.type == PARTITION_TYPE_OS2_HIDDEN_C_DRIVE)
         {
-            rc = load_mi4_part(loadbuffer, pinfo, MAX_LOADSIZE,
+            rc = load_mi4_part(loadbuffer, &pinfo, MAX_LOADSIZE,
                                usb == USB_INSERTED);
             if (rc <= EFILE_EMPTY) {
                 printf("Can't load from partition");
diff --git a/bootloader/mini2440.c b/bootloader/mini2440.c
index b3d73d1270..4088065550 100644
--- a/bootloader/mini2440.c
+++ b/bootloader/mini2440.c
@@ -29,6 +29,7 @@
 #include "lcd.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "fat.h"
 #include "disk.h"
 #include "font.h"
@@ -88,7 +89,7 @@ int main(void)
         error(EATA, rc, true);
     }
 
-    disk_init(IF_MD(0));
+    filesystem_init();
     rc = disk_mount_all();
     if (rc<=0)
     {
diff --git a/bootloader/mpio_hd200_hd300.c b/bootloader/mpio_hd200_hd300.c
index a4e13e1f88..e66732f848 100644
--- a/bootloader/mpio_hd200_hd300.c
+++ b/bootloader/mpio_hd200_hd300.c
@@ -29,6 +29,7 @@
 #include "lcd.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "usb.h"
 #include "disk.h"
 #include "font.h"
@@ -202,7 +203,7 @@ static void rb_boot(void)
     if(rc)
         error(EATA, rc, true);
 
-    disk_init();
+    filesystem_init();
 
     rc = disk_mount_all();
     if (rc <= 0)
diff --git a/bootloader/mrobe500.c b/bootloader/mrobe500.c
index 0b9ffb6281..08ba6f2acd 100644
--- a/bootloader/mrobe500.c
+++ b/bootloader/mrobe500.c
@@ -26,6 +26,7 @@
 #include "lcd.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "fat.h"
 #include "disk.h"
 #include "font.h"
@@ -123,8 +124,8 @@ void main(void)
         error(EATA, rc, true);
     }
 
-    printf("disk");
-    disk_init();
+    printf("filesystem");
+    filesystem_init();
 
     printf("mount");
     rc = disk_mount_all();
diff --git a/bootloader/ondavx747.c b/bootloader/ondavx747.c
index 3d03c36eae..0f1c504553 100644
--- a/bootloader/ondavx747.c
+++ b/bootloader/ondavx747.c
@@ -33,6 +33,7 @@
 #include "rb-loader.h"
 #include "loader_strerror.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "string.h"
 #include "adc.h"
@@ -269,6 +270,8 @@ int main(void)
 
     show_logo();
 
+    filesystem_init();
+
     rc = storage_init();
     if(rc)
         error(EATA, rc, true);
diff --git a/bootloader/rk27xx.c b/bootloader/rk27xx.c
index d190ea5a5a..57e5868a87 100644
--- a/bootloader/rk27xx.c
+++ b/bootloader/rk27xx.c
@@ -12,6 +12,7 @@
 #include "button.h"
 #include "common.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "panic.h"
 #include "power.h"
@@ -146,8 +147,7 @@ void main(void)
     if(ret < 0)
         error(EATA, ret, true);
 
-    while(!disk_init(IF_MV(0)))
-        panicf("disk_init failed!");
+    filesystem_init();
 
     while((ret = disk_mount_all()) <= 0)
         error(EDISK, ret, true);
diff --git a/bootloader/sansa_as3525.c b/bootloader/sansa_as3525.c
index 8592f2450f..01fb8459b4 100644
--- a/bootloader/sansa_as3525.c
+++ b/bootloader/sansa_as3525.c
@@ -39,6 +39,7 @@
 #include "rb-loader.h"
 #include "loader_strerror.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "panic.h"
 #include "power.h"
@@ -119,6 +120,8 @@ void main(void)
     if(ret < 0)
         error(EATA, ret, true);
 
+    filesystem_init();
+
 #ifdef USE_ROCKBOX_USB
     usb_init();
     usb_start_monitoring();
@@ -128,13 +131,6 @@ void main(void)
         usb_mode();
 #endif /* USE_ROCKBOX_USB */
 
-    while(!disk_init(IF_MV(0)))
-#ifdef USE_ROCKBOX_USB
-        usb_mode();
-#else
-        panicf("disk_init failed!");
-#endif
-
     while((ret = disk_mount_all()) <= 0)
     {
 #ifdef USE_ROCKBOX_USB
diff --git a/bootloader/sansaconnect.c b/bootloader/sansaconnect.c
index 48617ec337..5bd59b3ac4 100644
--- a/bootloader/sansaconnect.c
+++ b/bootloader/sansaconnect.c
@@ -21,6 +21,7 @@
 #include "lcd.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "disk.h"
 #include "font.h"
 #include "backlight.h"
@@ -72,7 +73,7 @@ void main(void)
     if(ret)
         printf("SD error: %d", ret);
 
-    disk_init(IF_MD(0));
+    filesystem_init();
 
     ret = disk_mount_all();
     if (ret <= 0)
diff --git a/bootloader/telechips.c b/bootloader/telechips.c
index 17ba509a6c..d2cf10eb21 100644
--- a/bootloader/telechips.c
+++ b/bootloader/telechips.c
@@ -30,6 +30,7 @@
 #include "lcd.h"
 #include "../kernel-internal.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "fat.h"
 #include "disk.h"
 #include "font.h"
@@ -162,6 +163,8 @@ void* main(void)
         error(EATA, rc, true);
     }
 
+    filesystem_init();
+
     printf("mount");
     rc = disk_mount_all();
     if (rc<=0)
diff --git a/bootloader/tpj1022.c b/bootloader/tpj1022.c
index 159dcc63cd..30adb6ba4e 100644
--- a/bootloader/tpj1022.c
+++ b/bootloader/tpj1022.c
@@ -31,6 +31,7 @@
 #include "kernel.h"
 #include "thread.h"
 #include "storage.h"
+#include "file_internal.h"
 #include "fat.h"
 #include "disk.h"
 #include "font.h"
@@ -56,7 +57,7 @@ void* main(void)
 
     i=storage_init();
 
-    disk_init();
+    filesystem_init();
     rc = disk_mount_all();
 
 #if 0