Changeset ed903174 in mainline for uspace/srv/bd/part/guid_part/guid_part.c

Timestamp:

2010-02-10T23:51:23Z (14 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e70edd1

Parents:

b32c604f

Message:

implement support for 64bit file offsets

• the libc API is a small deviation from standard, but we have no reason to keep a strict backward compatibility with ancient code so far
  • the basic signed 64bit offset type is called off64_t
    • lseek() and fseek() take off64_t arguments (since the argument represents a relative offset)
    • ftell() returns off64_t values (since it is a wrapper of lseek())
    • vfs_seek() implementation supports negative offsets when SEEK_CUR and SEEK_END is used
  • aoff64_t is used for internal unsigned representation of sizes (in bytes, blocks, etc.) and absolute offsets
    • mmap() and ftruncate() take aoff64_t arguments (since the full range of the absolute file offset should be used here)
    • struct stat stores the file size as aoff64_t
  • in both cases the explicit range of the types shown in the names is helpful for proper filesystem and IPC interaction
  • note: size_t should be used only for representing in-memory sizes and offsets, not device and file-related information, and vice versa
    • the code base still needs a thorough revision with respect to this rule
  • PRIdOFF64 and PRIuOFF64 can be used for printing the offsets
• VFS_OUT_LOOKUP returns the 64bit file size in two IPC arguments
  • since all 5 IPC arguments have already been taken, the fs_handle is returned as the return value (fs_handle has only 16 bits, thus the return value can be used for both indicating errors as negative values and returning positive handles)
• VFS_OUT_READ and VFS_OUT_WRITE use aoff64_t absolute offsets split into two IPC arguments

replace bn_t with aoff64_t as a generic 64bit bytes/block counter type

note: filesystem drivers need to be revised with respect to make sure that all out-of-range checks are correct (especially w.r.t. file and block offsets)

File:

• uspace/srv/bd/part/guid_part/guid_part.c (modified) (7 diffs)

uspace/srv/bd/part/guid_part/guid_part.c

@@ -79 +79 @@
         bool present;
         /** Address of first block */
-        bn_t start_addr;
+        aoff64_t start_addr;
         /** Number of blocks */
-        bn_t length;
+        aoff64_t length;
         /** Device representing the partition (outbound device) */
         dev_handle_t dev;
@@ -101 +101 @@
 static void gpt_pte_to_part(const gpt_entry_t *pte, part_t *part);
 static void gpt_connection(ipc_callid_t iid, ipc_call_t *icall);
-static int gpt_bd_read(part_t *p, bn_t ba, size_t cnt, void *buf);
-static int gpt_bd_write(part_t *p, bn_t ba, size_t cnt, const void *buf);
-static int gpt_bsa_translate(part_t *p, bn_t ba, size_t cnt, bn_t *gba);
+static int gpt_bd_read(part_t *p, aoff64_t ba, size_t cnt, void *buf);
+static int gpt_bd_write(part_t *p, aoff64_t ba, size_t cnt, const void *buf);
+static int gpt_bsa_translate(part_t *p, aoff64_t ba, size_t cnt, aoff64_t *gba);
 
 int main(int argc, char **argv)
@@ -199 +199 @@
                     / (1024 * 1024);
                 printf(NAME ": Registered device %s: %" PRIu64 " blocks "
-                    "%" PRIuBN " MB.\n", name, part->length, size_mb);
+                    "%" PRIuOFF64 " MB.\n", name, part->length, size_mb);
 
                 part->dev = dev;
@@ -319 +319 @@
         int flags;
         int retval;
-        bn_t ba;
+        aoff64_t ba;
         size_t cnt;
         part_t *part;
@@ -402 +402 @@
 
 /** Read blocks from partition. */
-static int gpt_bd_read(part_t *p, bn_t ba, size_t cnt, void *buf)
-{
-        bn_t gba;
+static int gpt_bd_read(part_t *p, aoff64_t ba, size_t cnt, void *buf)
+{
+        aoff64_t gba;
 
         if (gpt_bsa_translate(p, ba, cnt, &gba) != EOK)
@@ -413 +413 @@
 
 /** Write blocks to partition. */
-static int gpt_bd_write(part_t *p, bn_t ba, size_t cnt, const void *buf)
-{
-        bn_t gba;
+static int gpt_bd_write(part_t *p, aoff64_t ba, size_t cnt, const void *buf)
+{
+        aoff64_t gba;
 
         if (gpt_bsa_translate(p, ba, cnt, &gba) != EOK)
@@ -424 +424 @@
 
 /** Translate block segment address with range checking. */
-static int gpt_bsa_translate(part_t *p, bn_t ba, size_t cnt, bn_t *gba)
+static int gpt_bsa_translate(part_t *p, aoff64_t ba, size_t cnt, aoff64_t *gba)
 {
         if (ba + cnt > p->length)