Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block

[mirror_ubuntu-artful-kernel.git] / fs / adfs / inode.c

diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
index 1cc84b2761312ed82206a1a12d8b7d283bfed357..d5250c5aae21e10c560180e1042234d3a4d91f25 100644 (file)
--- a/fs/adfs/inode.c
+++ b/fs/adfs/inode.c
@@ -7,7 +7,6 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include "adfs.h"
@@ -78,26 +77,13 @@ static const struct address_space_operations adfs_aops = {
        .bmap           = _adfs_bmap
 };
 
-static inline unsigned int
-adfs_filetype(struct inode *inode)
-{
-       unsigned int type;
-
-       if (ADFS_I(inode)->stamped)
-               type = (ADFS_I(inode)->loadaddr >> 8) & 0xfff;
-       else
-               type = (unsigned int) -1;
-
-       return type;
-}
-
 /*
  * Convert ADFS attributes and filetype to Linux permission.
  */
 static umode_t
 adfs_atts2mode(struct super_block *sb, struct inode *inode)
 {
-       unsigned int filetype, attr = ADFS_I(inode)->attr;
+       unsigned int attr = ADFS_I(inode)->attr;
        umode_t mode, rmask;
        struct adfs_sb_info *asb = ADFS_SB(sb);
 
@@ -106,9 +92,7 @@ adfs_atts2mode(struct super_block *sb, struct inode *inode)
                return S_IFDIR | S_IXUGO | mode;
        }
 
-       filetype = adfs_filetype(inode);
-
-       switch (filetype) {
+       switch (ADFS_I(inode)->filetype) {
        case 0xfc0:     /* LinkFS */
                return S_IFLNK|S_IRWXUGO;
 
@@ -174,50 +158,48 @@ adfs_mode2atts(struct super_block *sb, struct inode *inode)
 
 /*
  * Convert an ADFS time to Unix time.  ADFS has a 40-bit centi-second time
- * referenced to 1 Jan 1900 (til 2248)
+ * referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds
+ * of time to convert from RISC OS epoch to Unix epoch.
  */
 static void
 adfs_adfs2unix_time(struct timespec *tv, struct inode *inode)
 {
        unsigned int high, low;
+       /* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
+        * 01 Jan 1900 00:00:00 (RISC OS epoch)
+        */
+       static const s64 nsec_unix_epoch_diff_risc_os_epoch =
+                                                       2208988800000000000LL;
+       s64 nsec;
 
        if (ADFS_I(inode)->stamped == 0)
                goto cur_time;
 
-       high = ADFS_I(inode)->loadaddr << 24;
-       low  = ADFS_I(inode)->execaddr;
+       high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */
+       low  = ADFS_I(inode)->execaddr;    /* bottom 32 bits of timestamp */
 
-       high |= low >> 8;
-       low  &= 255;
+       /* convert 40-bit centi-seconds to 32-bit seconds
+        * going via nanoseconds to retain precision
+        */
+       nsec = (((s64) high << 32) | (s64) low) * 10000000; /* cs to ns */
 
        /* Files dated pre  01 Jan 1970 00:00:00. */
-       if (high < 0x336e996a)
+       if (nsec < nsec_unix_epoch_diff_risc_os_epoch)
                goto too_early;
 
-       /* Files dated post 18 Jan 2038 03:14:05. */
-       if (high >= 0x656e9969)
-               goto too_late;
-
-       /* discard 2208988800 (0x336e996a00) seconds of time */
-       high -= 0x336e996a;
+       /* convert from RISC OS to Unix epoch */
+       nsec -= nsec_unix_epoch_diff_risc_os_epoch;
 
-       /* convert 40-bit centi-seconds to 32-bit seconds */
-       tv->tv_sec = (((high % 100) << 8) + low) / 100 + (high / 100 << 8);
-       tv->tv_nsec = 0;
+       *tv = ns_to_timespec(nsec);
        return;
 
  cur_time:
-       *tv = CURRENT_TIME_SEC;
+       *tv = CURRENT_TIME;
        return;
 
  too_early:
        tv->tv_sec = tv->tv_nsec = 0;
        return;
-
- too_late:
-       tv->tv_sec = 0x7ffffffd;
-       tv->tv_nsec = 0;
-       return;
 }
 
 /*
@@ -279,7 +261,8 @@ adfs_iget(struct super_block *sb, struct object_info *obj)
        ADFS_I(inode)->loadaddr  = obj->loadaddr;
        ADFS_I(inode)->execaddr  = obj->execaddr;
        ADFS_I(inode)->attr      = obj->attr;
-       ADFS_I(inode)->stamped    = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
+       ADFS_I(inode)->filetype  = obj->filetype;
+       ADFS_I(inode)->stamped   = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
 
        inode->i_mode    = adfs_atts2mode(sb, inode);
        adfs_adfs2unix_time(&inode->i_mtime, inode);
@@ -315,8 +298,6 @@ adfs_notify_change(struct dentry *dentry, struct iattr *attr)
        unsigned int ia_valid = attr->ia_valid;
        int error;
        
-       lock_kernel();
-
        error = inode_change_ok(inode, attr);
 
        /*
@@ -358,7 +339,6 @@ adfs_notify_change(struct dentry *dentry, struct iattr *attr)
        if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
                mark_inode_dirty(inode);
 out:
-       unlock_kernel();
        return error;
 }
 
@@ -373,7 +353,6 @@ int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
        struct object_info obj;
        int ret;
 
-       lock_kernel();
        obj.file_id     = inode->i_ino;
        obj.name_len    = 0;
        obj.parent_id   = ADFS_I(inode)->parent_id;
@@ -383,6 +362,5 @@ int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
        obj.size        = inode->i_size;
 
        ret = adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
-       unlock_kernel();
        return ret;
 }