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Diffstat (limited to 'fs/udf/inode.c')
-rw-r--r--fs/udf/inode.c192
1 files changed, 157 insertions, 35 deletions
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 2171bcfeec20..c8461551e108 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -356,9 +356,106 @@ udf_getblk(struct inode *inode, long block, int create, int *err)
return NULL;
}
+/* Extend the file by 'blocks' blocks, return the number of extents added */
+int udf_extend_file(struct inode *inode, struct extent_position *last_pos,
+ kernel_long_ad *last_ext, sector_t blocks)
+{
+ sector_t add;
+ int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
+ struct super_block *sb = inode->i_sb;
+ kernel_lb_addr prealloc_loc = {0, 0};
+ int prealloc_len = 0;
+
+ /* The previous extent is fake and we should not extend by anything
+ * - there's nothing to do... */
+ if (!blocks && fake)
+ return 0;
+ /* Round the last extent up to a multiple of block size */
+ if (last_ext->extLength & (sb->s_blocksize - 1)) {
+ last_ext->extLength =
+ (last_ext->extLength & UDF_EXTENT_FLAG_MASK) |
+ (((last_ext->extLength & UDF_EXTENT_LENGTH_MASK) +
+ sb->s_blocksize - 1) & ~(sb->s_blocksize - 1));
+ UDF_I_LENEXTENTS(inode) =
+ (UDF_I_LENEXTENTS(inode) + sb->s_blocksize - 1) &
+ ~(sb->s_blocksize - 1);
+ }
+ /* Last extent are just preallocated blocks? */
+ if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) == EXT_NOT_RECORDED_ALLOCATED) {
+ /* Save the extent so that we can reattach it to the end */
+ prealloc_loc = last_ext->extLocation;
+ prealloc_len = last_ext->extLength;
+ /* Mark the extent as a hole */
+ last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
+ (last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
+ last_ext->extLocation.logicalBlockNum = 0;
+ last_ext->extLocation.partitionReferenceNum = 0;
+ }
+ /* Can we merge with the previous extent? */
+ if ((last_ext->extLength & UDF_EXTENT_FLAG_MASK) == EXT_NOT_RECORDED_NOT_ALLOCATED) {
+ add = ((1<<30) - sb->s_blocksize - (last_ext->extLength &
+ UDF_EXTENT_LENGTH_MASK)) >> sb->s_blocksize_bits;
+ if (add > blocks)
+ add = blocks;
+ blocks -= add;
+ last_ext->extLength += add << sb->s_blocksize_bits;
+ }
+
+ if (fake) {
+ udf_add_aext(inode, last_pos, last_ext->extLocation,
+ last_ext->extLength, 1);
+ count++;
+ }
+ else
+ udf_write_aext(inode, last_pos, last_ext->extLocation, last_ext->extLength, 1);
+ /* Managed to do everything necessary? */
+ if (!blocks)
+ goto out;
+
+ /* All further extents will be NOT_RECORDED_NOT_ALLOCATED */
+ last_ext->extLocation.logicalBlockNum = 0;
+ last_ext->extLocation.partitionReferenceNum = 0;
+ add = (1 << (30-sb->s_blocksize_bits)) - 1;
+ last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED | (add << sb->s_blocksize_bits);
+ /* Create enough extents to cover the whole hole */
+ while (blocks > add) {
+ blocks -= add;
+ if (udf_add_aext(inode, last_pos, last_ext->extLocation,
+ last_ext->extLength, 1) == -1)
+ return -1;
+ count++;
+ }
+ if (blocks) {
+ last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
+ (blocks << sb->s_blocksize_bits);
+ if (udf_add_aext(inode, last_pos, last_ext->extLocation,
+ last_ext->extLength, 1) == -1)
+ return -1;
+ count++;
+ }
+out:
+ /* Do we have some preallocated blocks saved? */
+ if (prealloc_len) {
+ if (udf_add_aext(inode, last_pos, prealloc_loc, prealloc_len, 1) == -1)
+ return -1;
+ last_ext->extLocation = prealloc_loc;
+ last_ext->extLength = prealloc_len;
+ count++;
+ }
+ /* last_pos should point to the last written extent... */
+ if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
+ last_pos->offset -= sizeof(short_ad);
+ else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
+ last_pos->offset -= sizeof(long_ad);
+ else
+ return -1;
+ return count;
+}
+
static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
int *err, long *phys, int *new)
{
+ static sector_t last_block;
struct buffer_head *result = NULL;
kernel_long_ad laarr[EXTENT_MERGE_SIZE];
struct extent_position prev_epos, cur_epos, next_epos;
@@ -371,7 +468,7 @@ static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
sector_t offset = 0;
int8_t etype;
int goal = 0, pgoal = UDF_I_LOCATION(inode).logicalBlockNum;
- char lastblock = 0;
+ int lastblock = 0;
prev_epos.offset = udf_file_entry_alloc_offset(inode);
prev_epos.block = UDF_I_LOCATION(inode);
@@ -423,6 +520,8 @@ static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
b_off -= lbcount;
offset = b_off >> inode->i_sb->s_blocksize_bits;
+ /* Move into indirect extent if we are at a pointer to it */
+ udf_next_aext(inode, &prev_epos, &eloc, &elen, 0);
/* if the extent is allocated and recorded, return the block
if the extent is not a multiple of the blocksize, round up */
@@ -444,43 +543,66 @@ static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
return NULL;
}
+ last_block = block;
+ /* Are we beyond EOF? */
if (etype == -1)
{
- endnum = startnum = ((count > 1) ? 1 : count);
- if (laarr[c].extLength & (inode->i_sb->s_blocksize - 1))
- {
- laarr[c].extLength =
- (laarr[c].extLength & UDF_EXTENT_FLAG_MASK) |
- (((laarr[c].extLength & UDF_EXTENT_LENGTH_MASK) +
- inode->i_sb->s_blocksize - 1) &
- ~(inode->i_sb->s_blocksize - 1));
- UDF_I_LENEXTENTS(inode) =
- (UDF_I_LENEXTENTS(inode) + inode->i_sb->s_blocksize - 1) &
- ~(inode->i_sb->s_blocksize - 1);
+ int ret;
+
+ if (count) {
+ if (c)
+ laarr[0] = laarr[1];
+ startnum = 1;
+ }
+ else {
+ /* Create a fake extent when there's not one */
+ memset(&laarr[0].extLocation, 0x00, sizeof(kernel_lb_addr));
+ laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
+ /* Will udf_extend_file() create real extent from a fake one? */
+ startnum = (offset > 0);
+ }
+ /* Create extents for the hole between EOF and offset */
+ ret = udf_extend_file(inode, &prev_epos, laarr, offset);
+ if (ret == -1) {
+ brelse(prev_epos.bh);
+ brelse(cur_epos.bh);
+ brelse(next_epos.bh);
+ /* We don't really know the error here so we just make
+ * something up */
+ *err = -ENOSPC;
+ return NULL;
}
- c = !c;
- laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
- ((offset + 1) << inode->i_sb->s_blocksize_bits);
- memset(&laarr[c].extLocation, 0x00, sizeof(kernel_lb_addr));
- count ++;
- endnum ++;
+ c = 0;
+ offset = 0;
+ count += ret;
+ /* We are not covered by a preallocated extent? */
+ if ((laarr[0].extLength & UDF_EXTENT_FLAG_MASK) != EXT_NOT_RECORDED_ALLOCATED) {
+ /* Is there any real extent? - otherwise we overwrite
+ * the fake one... */
+ if (count)
+ c = !c;
+ laarr[c].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
+ inode->i_sb->s_blocksize;
+ memset(&laarr[c].extLocation, 0x00, sizeof(kernel_lb_addr));
+ count ++;
+ endnum ++;
+ }
+ endnum = c+1;
lastblock = 1;
}
- else
+ else {
endnum = startnum = ((count > 2) ? 2 : count);
- /* if the current extent is in position 0, swap it with the previous */
- if (!c && count != 1)
- {
- laarr[2] = laarr[0];
- laarr[0] = laarr[1];
- laarr[1] = laarr[2];
- c = 1;
- }
+ /* if the current extent is in position 0, swap it with the previous */
+ if (!c && count != 1)
+ {
+ laarr[2] = laarr[0];
+ laarr[0] = laarr[1];
+ laarr[1] = laarr[2];
+ c = 1;
+ }
- /* if the current block is located in a extent, read the next extent */
- if (etype != -1)
- {
+ /* if the current block is located in an extent, read the next extent */
if ((etype = udf_next_aext(inode, &next_epos, &eloc, &elen, 0)) != -1)
{
laarr[c+1].extLength = (etype << 30) | elen;
@@ -489,11 +611,10 @@ static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
startnum ++;
endnum ++;
}
- else
+ else {
lastblock = 1;
+ }
}
- brelse(cur_epos.bh);
- brelse(next_epos.bh);
/* if the current extent is not recorded but allocated, get the
block in the extent corresponding to the requested block */
@@ -534,8 +655,8 @@ static struct buffer_head * inode_getblk(struct inode * inode, sector_t block,
udf_merge_extents(inode, laarr, &endnum);
/* write back the new extents, inserting new extents if the new number
- of extents is greater than the old number, and deleting extents if
- the new number of extents is less than the old number */
+ of extents is greater than the old number, and deleting extents if
+ the new number of extents is less than the old number */
udf_update_extents(inode, laarr, startnum, endnum, &prev_epos);
brelse(prev_epos.bh);
@@ -991,6 +1112,7 @@ __udf_read_inode(struct inode *inode)
return;
}
udf_fill_inode(inode, bh);
+
brelse(bh);
}