udf: fix adding entry to a directory
[safe/jmp/linux-2.6] / fs / udf / truncate.c
index 7dc8a55..fe61be1 100644 (file)
@@ -4,11 +4,6 @@
  * PURPOSE
  *     Truncate handling routines for the OSTA-UDF(tm) filesystem.
  *
- * CONTACTS
- *     E-mail regarding any portion of the Linux UDF file system should be
- *     directed to the development team mailing list (run by majordomo):
- *             linux_udf@hpesjro.fc.hp.com
- *
  * COPYRIGHT
  *     This file is distributed under the terms of the GNU General Public
  *     License (GPL). Copies of the GPL can be obtained from:
 #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;
-       int first_block = (nelen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
+       kernel_lb_addr neloc = {};
+       int last_block = (elen + inode->i_sb->s_blocksize - 1) >>
+               inode->i_sb->s_blocksize_bits;
+       int first_block = (nelen + inode->i_sb->s_blocksize - 1) >>
+               inode->i_sb->s_blocksize_bits;
 
-       if (nelen)
-       {
-               if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
-               {
-                       udf_free_blocks(inode->i_sb, inode, eloc, 0, last_block);
+       if (nelen) {
+               if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
+                       udf_free_blocks(inode->i_sb, inode, eloc, 0,
+                                       last_block);
                        etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
-               }
-               else
+               } else
                        neloc = eloc;
                nelen = (etype << 30) | nelen;
        }
 
-       if (elen != nelen)
-       {
-               udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
-               if (last_block - first_block > 0)
-               {
+       if (elen != nelen) {
+               udf_write_aext(inode, epos, neloc, nelen, 0);
+               if (last_block - first_block > 0) {
                        if (etype == (EXT_RECORDED_ALLOCATED >> 30))
                                mark_inode_dirty(inode);
 
                        if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
-                               udf_free_blocks(inode->i_sb, inode, eloc, first_block, last_block - first_block);
+                               udf_free_blocks(inode->i_sb, inode, eloc,
+                                               first_block,
+                                               last_block - first_block);
                }
        }
 }
 
-void udf_discard_prealloc(struct inode * inode)
+/*
+ * Truncate the last extent to match i_size. This function assumes
+ * that preallocation extent is already truncated.
+ */
+void udf_truncate_tail_extent(struct inode *inode)
 {
-       kernel_lb_addr bloc, eloc;
-       uint32_t extoffset = 0, elen, nelen;
+       struct extent_position epos = {};
+       kernel_lb_addr eloc;
+       uint32_t elen, nelen;
        uint64_t lbcount = 0;
        int8_t etype = -1, netype;
-       struct buffer_head *bh = NULL;
        int adsize;
+       struct udf_inode_info *iinfo = UDF_I(inode);
 
-       if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
-               inode->i_size == UDF_I_LENEXTENTS(inode))
-       {
+       if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
+           inode->i_size == iinfo->i_lenExtents)
+               return;
+       /* Are we going to delete the file anyway? */
+       if (inode->i_nlink == 0)
                return;
+
+       if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+               adsize = sizeof(short_ad);
+       else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+               adsize = sizeof(long_ad);
+       else
+               BUG();
+
+       /* 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) {
+                       if (lbcount - inode->i_size >= inode->i_sb->s_blocksize)
+                               printk(KERN_WARNING
+                                      "udf_truncate_tail_extent(): Too long "
+                                      "extent after EOF in inode %u: i_size: "
+                                      "%Ld lbcount: %Ld extent %u+%u\n",
+                                      (unsigned)inode->i_ino,
+                                      (long long)inode->i_size,
+                                      (long long)lbcount,
+                                      (unsigned)eloc.logicalBlockNum,
+                                      (unsigned)elen);
+                       nelen = elen - (lbcount - inode->i_size);
+                       epos.offset -= adsize;
+                       extent_trunc(inode, &epos, eloc, etype, elen, nelen);
+                       epos.offset += adsize;
+                       if (udf_next_aext(inode, &epos, &eloc, &elen, 1) != -1)
+                               printk(KERN_ERR "udf_truncate_tail_extent(): "
+                                      "Extent after EOF in inode %u.\n",
+                                      (unsigned)inode->i_ino);
+                       break;
+               }
        }
+       /* This inode entry is in-memory only and thus we don't have to mark
+        * the inode dirty */
+       iinfo->i_lenExtents = inode->i_size;
+       brelse(epos.bh);
+}
+
+void udf_discard_prealloc(struct inode *inode)
+{
+       struct extent_position epos = { NULL, 0, {0, 0} };
+       kernel_lb_addr eloc;
+       uint32_t elen;
+       uint64_t lbcount = 0;
+       int8_t etype = -1, netype;
+       int adsize;
+       struct udf_inode_info *iinfo = UDF_I(inode);
+
+       if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
+           inode->i_size == iinfo->i_lenExtents)
+               return;
 
-       if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
+       if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
                adsize = sizeof(short_ad);
-       else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
+       else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
                adsize = sizeof(long_ad);
        else
                adsize = 0;
 
-       bloc = UDF_I_LOCATION(inode);
+       epos.block = iinfo->i_location;
 
-       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)
-               {
-                       nelen = elen - (lbcount - inode->i_size);
-                       extent_trunc(inode, bloc, extoffset-adsize, eloc, etype, elen, bh, nelen);
-                       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)
-               {
-                       UDF_I_LENALLOC(inode) = extoffset - udf_file_entry_alloc_offset(inode);
+               extent_trunc(inode, &epos, eloc, etype, elen, 0);
+               if (!epos.bh) {
+                       iinfo->i_lenAlloc =
+                               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));
-                       if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
-                               udf_update_tag(bh->b_data, extoffset);
+               } else {
+                       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(inode->i_sb)->s_udfrev >= 0x0201)
+                               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);
+       /* This inode entry is in-memory only and thus we don't have to mark
+        * the inode dirty */
+       iinfo->i_lenExtents = lbcount;
+       brelse(epos.bh);
 }
 
-void udf_truncate_extents(struct inode * inode)
+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 = {};
+       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;
+       struct udf_sb_info *sbi = UDF_SB(sb);
+       sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
+       loff_t byte_offset;
        int adsize;
+       struct udf_inode_info *iinfo = UDF_I(inode);
 
-       if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
+       if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
                adsize = sizeof(short_ad);
-       else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
+       else if (iinfo->i_alloc_type == 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));
-       if (etype != -1)
-       {
-               extoffset -= adsize;
-               extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, offset);
-               extoffset += adsize;
-
-               if (offset)
-                       lenalloc = extoffset;
+       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) {
+               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)
-               {
-                       if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30))
-                       {
-                               udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
-                               extoffset = 0;
-                               if (lelen)
-                               {
-                                       if (!bh)
+               while ((etype = udf_current_aext(inode, &epos, &eloc,
+                                                &elen, 0)) != -1) {
+                       if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
+                               udf_write_aext(inode, &epos, neloc, nelen, 0);
+                               if (indirect_ext_len) {
+                                       /* 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);
-                               }
-                               else
-                               {
-                                       if (!bh)
-                                       {
-                                               UDF_I_LENALLOC(inode) = lenalloc;
+                                       udf_free_blocks(sb, inode, epos.block,
+                                                       0, indirect_ext_len);
+                               } else {
+                                       if (!epos.bh) {
+                                               iinfo->i_lenAlloc =
+                                                               lenalloc;
                                                mark_inode_dirty(inode);
-                                       }
-                                       else
-                                       {
-                                               struct allocExtDesc *aed = (struct allocExtDesc *)(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 +
-                                                               sizeof(struct allocExtDesc));
-                                               else
-                                                       udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
-                                               mark_buffer_dirty_inode(bh, inode);
+                                       } else {
+                                               struct allocExtDesc *aed =
+                                                       (struct allocExtDesc *)
+                                                       (epos.bh->b_data);
+                                               int len =
+                                                   sizeof(struct allocExtDesc);
+
+                                               aed->lengthAllocDescs =
+                                                   cpu_to_le32(lenalloc);
+                                               if (!UDF_QUERY_FLAG(sb,
+                                                       UDF_FLAG_STRICT) ||
+                                                   sbi->s_udfrev >= 0x0201)
+                                                       len += lenalloc;
+
+                                               udf_update_tag(epos.bh->b_data,
+                                                               len);
+                                               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;
-                       }
-                       else
-                       {
-                               extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0);
-                               extoffset += adsize;
+                                       indirect_ext_len = 1;
+                       } else {
+                               extent_trunc(inode, &epos, eloc, etype,
+                                            elen, 0);
+                               epos.offset += adsize;
                        }
                }
 
-               if (lelen)
-               {
-                       if (!bh)
+               if (indirect_ext_len) {
+                       if (!epos.bh)
                                BUG();
-                       else
-                               memset(bh->b_data, 0x00, sizeof(struct allocExtDesc));
-                       udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen);
-               }
-               else
-               {
-                       if (!bh)
-                       {
-                               UDF_I_LENALLOC(inode) = lenalloc;
+                       udf_free_blocks(sb, inode, epos.block, 0,
+                                       indirect_ext_len);
+               } else {
+                       if (!epos.bh) {
+                               iinfo->i_lenAlloc = lenalloc;
                                mark_inode_dirty(inode);
-                       }
-                       else
-                       {
-                               struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data);
+                       } else {
+                               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) ||
+                                   sbi->s_udfrev >= 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)
-               {
-                       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);
+       } else if (inode->i_size) {
+               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' blocks.
+                        */
+                       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 {
+                               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;
+       iinfo->i_lenExtents = inode->i_size;
 
-       udf_release_data(bh);
+       brelse(epos.bh);
 }