fedora core 6 1.2949 + vserver 2.2.0
[linux-2.6.git] / fs / udf / truncate.c
index 0abd66c..77975ae 100644 (file)
@@ -28,8 +28,8 @@
 #include "udf_i.h"
 #include "udf_sb.h"
 
-static void extent_trunc(struct inode * inode, kernel_lb_addr bloc, int extoffset,
-       kernel_lb_addr eloc, int8_t etype, uint32_t elen, struct buffer_head *bh, uint32_t nelen)
+static void extent_trunc(struct inode * inode, struct extent_position *epos,
+       kernel_lb_addr eloc, int8_t etype, uint32_t elen, uint32_t nelen)
 {
        kernel_lb_addr neloc = { 0, 0 };
        int last_block = (elen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
@@ -49,7 +49,7 @@ static void extent_trunc(struct inode * inode, kernel_lb_addr bloc, int extoffse
 
        if (elen != nelen)
        {
-               udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
+               udf_write_aext(inode, epos, neloc, nelen, 0);
                if (last_block - first_block > 0)
                {
                        if (etype == (EXT_RECORDED_ALLOCATED >> 30))
@@ -63,18 +63,16 @@ static void extent_trunc(struct inode * inode, kernel_lb_addr bloc, int extoffse
 
 void udf_discard_prealloc(struct inode * inode)
 {
-       kernel_lb_addr bloc, eloc;
-       uint32_t extoffset = 0, elen, nelen;
+       struct extent_position epos = { NULL, 0, {0, 0}};
+       kernel_lb_addr eloc;
+       uint32_t elen, nelen;
        uint64_t lbcount = 0;
        int8_t etype = -1, netype;
-       struct buffer_head *bh = NULL;
        int adsize;
 
        if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
                inode->i_size == UDF_I_LENEXTENTS(inode))
-       {
                return;
-       }
 
        if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
                adsize = sizeof(short_ad);
@@ -83,52 +81,58 @@ void udf_discard_prealloc(struct inode * inode)
        else
                adsize = 0;
 
-       bloc = UDF_I_LOCATION(inode);
+       epos.block = UDF_I_LOCATION(inode);
 
-       while ((netype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1)
+       /* Find the last extent in the file */
+       while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1)
        {
                etype = netype;
                lbcount += elen;
-               if (lbcount > inode->i_size && lbcount - inode->i_size < inode->i_sb->s_blocksize)
+               if (lbcount > inode->i_size && lbcount - elen < inode->i_size)
                {
+                       WARN_ON(lbcount - inode->i_size >= inode->i_sb->s_blocksize);
                        nelen = elen - (lbcount - inode->i_size);
-                       extent_trunc(inode, bloc, extoffset-adsize, eloc, etype, elen, bh, nelen);
+                       epos.offset -= adsize;
+                       extent_trunc(inode, &epos, eloc, etype, elen, nelen);
+                       epos.offset += adsize;
                        lbcount = inode->i_size;
                }
        }
-       if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
-       {
-               extoffset -= adsize;
+       if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
+               epos.offset -= adsize;
                lbcount -= elen;
-               extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0);
-               if (!bh)
+               extent_trunc(inode, &epos, eloc, etype, elen, 0);
+               if (!epos.bh)
                {
-                       UDF_I_LENALLOC(inode) = extoffset - udf_file_entry_alloc_offset(inode);
+                       UDF_I_LENALLOC(inode) = epos.offset - udf_file_entry_alloc_offset(inode);
                        mark_inode_dirty(inode);
                }
                else
                {
-                       struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data);
-                       aed->lengthAllocDescs = cpu_to_le32(extoffset - sizeof(struct allocExtDesc));
+                       struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
+                       aed->lengthAllocDescs = cpu_to_le32(epos.offset - sizeof(struct allocExtDesc));
                        if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
-                               udf_update_tag(bh->b_data, extoffset);
+                               udf_update_tag(epos.bh->b_data, epos.offset);
                        else
-                               udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
-                       mark_buffer_dirty_inode(bh, inode);
+                               udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
+                       mark_buffer_dirty_inode(epos.bh, inode);
                }
        }
        UDF_I_LENEXTENTS(inode) = lbcount;
 
-       udf_release_data(bh);
+       WARN_ON(lbcount != inode->i_size);
+       brelse(epos.bh);
 }
 
 void udf_truncate_extents(struct inode * inode)
 {
-       kernel_lb_addr bloc, eloc, neloc = { 0, 0 };
-       uint32_t extoffset, elen, offset, nelen = 0, lelen = 0, lenalloc;
+       struct extent_position epos;
+       kernel_lb_addr eloc, neloc = { 0, 0 };
+       uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
        int8_t etype;
-       int first_block = inode->i_size >> inode->i_sb->s_blocksize_bits;
-       struct buffer_head *bh = NULL;
+       struct super_block *sb = inode->i_sb;
+       sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
+       loff_t byte_offset;
        int adsize;
 
        if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
@@ -136,158 +140,130 @@ void udf_truncate_extents(struct inode * inode)
        else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
                adsize = sizeof(long_ad);
        else
-               adsize = 0;
+               BUG();
 
-       etype = inode_bmap(inode, first_block, &bloc, &extoffset, &eloc, &elen, &offset, &bh);
-       offset += (inode->i_size & (inode->i_sb->s_blocksize - 1));
+       etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
+       byte_offset = (offset << sb->s_blocksize_bits) + (inode->i_size & (sb->s_blocksize-1));
        if (etype != -1)
        {
-               extoffset -= adsize;
-               extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, offset);
-               extoffset += adsize;
-
-               if (offset)
-                       lenalloc = extoffset;
+               epos.offset -= adsize;
+               extent_trunc(inode, &epos, eloc, etype, elen, byte_offset);
+               epos.offset += adsize;
+               if (byte_offset)
+                       lenalloc = epos.offset;
                else
-                       lenalloc = extoffset - adsize;
+                       lenalloc = epos.offset - adsize;
 
-               if (!bh)
+               if (!epos.bh)
                        lenalloc -= udf_file_entry_alloc_offset(inode);
                else
                        lenalloc -= sizeof(struct allocExtDesc);
 
-               while ((etype = udf_current_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 0)) != -1)
+               while ((etype = udf_current_aext(inode, &epos, &eloc, &elen, 0)) != -1)
                {
                        if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30))
                        {
-                               udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
-                               extoffset = 0;
-                               if (lelen)
+                               udf_write_aext(inode, &epos, neloc, nelen, 0);
+                               if (indirect_ext_len)
                                {
-                                       if (!bh)
+                                       /* We managed to free all extents in the
+                                        * indirect extent - free it too */
+                                       if (!epos.bh)
                                                BUG();
-                                       else
-                                               memset(bh->b_data, 0x00, sizeof(struct allocExtDesc));
-                                       udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen);
+                                       udf_free_blocks(sb, inode, epos.block, 0, indirect_ext_len);
                                }
                                else
                                {
-                                       if (!bh)
+                                       if (!epos.bh)
                                        {
                                                UDF_I_LENALLOC(inode) = lenalloc;
                                                mark_inode_dirty(inode);
                                        }
                                        else
                                        {
-                                               struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data);
+                                               struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
                                                aed->lengthAllocDescs = cpu_to_le32(lenalloc);
-                                               if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
-                                                       udf_update_tag(bh->b_data, lenalloc +
+                                               if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(sb) >= 0x0201)
+                                                       udf_update_tag(epos.bh->b_data, lenalloc +
                                                                sizeof(struct allocExtDesc));
                                                else
-                                                       udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
-                                               mark_buffer_dirty_inode(bh, inode);
+                                                       udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
+                                               mark_buffer_dirty_inode(epos.bh, inode);
                                        }
                                }
-
-                               udf_release_data(bh);
-                               extoffset = sizeof(struct allocExtDesc);
-                               bloc = eloc;
-                               bh = udf_tread(inode->i_sb, udf_get_lb_pblock(inode->i_sb, bloc, 0));
+                               brelse(epos.bh);
+                               epos.offset = sizeof(struct allocExtDesc);
+                               epos.block = eloc;
+                               epos.bh = udf_tread(sb, udf_get_lb_pblock(sb, eloc, 0));
                                if (elen)
-                                       lelen = (elen + inode->i_sb->s_blocksize - 1) >>
-                                               inode->i_sb->s_blocksize_bits;
+                                       indirect_ext_len = (elen +
+                                               sb->s_blocksize - 1) >>
+                                               sb->s_blocksize_bits;
                                else
-                                       lelen = 1;
+                                       indirect_ext_len = 1;
                        }
                        else
                        {
-                               extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0);
-                               extoffset += adsize;
+                               extent_trunc(inode, &epos, eloc, etype, elen, 0);
+                               epos.offset += adsize;
                        }
                }
 
-               if (lelen)
+               if (indirect_ext_len)
                {
-                       if (!bh)
+                       if (!epos.bh)
                                BUG();
-                       else
-                               memset(bh->b_data, 0x00, sizeof(struct allocExtDesc));
-                       udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen);
+                       udf_free_blocks(sb, inode, epos.block, 0, indirect_ext_len);
                }
                else
                {
-                       if (!bh)
+                       if (!epos.bh)
                        {
                                UDF_I_LENALLOC(inode) = lenalloc;
                                mark_inode_dirty(inode);
                        }
                        else
                        {
-                               struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data);
+                               struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
                                aed->lengthAllocDescs = cpu_to_le32(lenalloc);
-                               if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
-                                       udf_update_tag(bh->b_data, lenalloc +
+                               if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(sb) >= 0x0201)
+                                       udf_update_tag(epos.bh->b_data, lenalloc +
                                                sizeof(struct allocExtDesc));
                                else
-                                       udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
-                               mark_buffer_dirty_inode(bh, inode);
+                                       udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
+                               mark_buffer_dirty_inode(epos.bh, inode);
                        }
                }
        }
        else if (inode->i_size)
        {
-               if (offset)
+               if (byte_offset)
                {
+                       kernel_long_ad extent;
+
                        /*
                         *  OK, there is not extent covering inode->i_size and
                         *  no extent above inode->i_size => truncate is
-                        *  extending the file by 'offset'.
+                        *  extending the file by 'offset' blocks.
                         */
-                       if ((!bh && extoffset == udf_file_entry_alloc_offset(inode)) ||
-                           (bh && extoffset == sizeof(struct allocExtDesc))) {
-                               /* File has no extents at all! */
-                               memset(&eloc, 0x00, sizeof(kernel_lb_addr));
-                               elen = EXT_NOT_RECORDED_NOT_ALLOCATED | offset;
-                               udf_add_aext(inode, &bloc, &extoffset, eloc, elen, &bh, 1);
+                       if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
+                           (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
+                               /* File has no extents at all or has empty last
+                                * indirect extent! Create a fake extent... */
+                               extent.extLocation.logicalBlockNum = 0;
+                               extent.extLocation.partitionReferenceNum = 0;
+                               extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
                        }
                        else {
-                               extoffset -= adsize;
-                               etype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1);
-                               if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
-                               {
-                                       extoffset -= adsize;
-                                       elen = EXT_NOT_RECORDED_NOT_ALLOCATED | (elen + offset);
-                                       udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 0);
-                               }
-                               else if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
-                               {
-                                       kernel_lb_addr neloc = { 0, 0 };
-                                       extoffset -= adsize;
-                                       nelen = EXT_NOT_RECORDED_NOT_ALLOCATED |
-                                               ((elen + offset + inode->i_sb->s_blocksize - 1) &
-                                               ~(inode->i_sb->s_blocksize - 1));
-                                       udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 1);
-                                       udf_add_aext(inode, &bloc, &extoffset, eloc, (etype << 30) | elen, &bh, 1);
-                               }
-                               else
-                               {
-                                       if (elen & (inode->i_sb->s_blocksize - 1))
-                                       {
-                                               extoffset -= adsize;
-                                               elen = EXT_RECORDED_ALLOCATED |
-                                                       ((elen + inode->i_sb->s_blocksize - 1) &
-                                                       ~(inode->i_sb->s_blocksize - 1));
-                                               udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 1);
-                                       }
-                                       memset(&eloc, 0x00, sizeof(kernel_lb_addr));
-                                       elen = EXT_NOT_RECORDED_NOT_ALLOCATED | offset;
-                                       udf_add_aext(inode, &bloc, &extoffset, eloc, elen, &bh, 1);
-                               }
+                               epos.offset -= adsize;
+                               etype = udf_next_aext(inode, &epos,
+                                       &extent.extLocation, &extent.extLength, 0);
+                               extent.extLength |= etype << 30;
                        }
+                       udf_extend_file(inode, &epos, &extent, offset+((inode->i_size & (sb->s_blocksize-1)) != 0));
                }
        }
        UDF_I_LENEXTENTS(inode) = inode->i_size;
 
-       udf_release_data(bh);
+       brelse(epos.bh);
 }