17  * Find a number of contiguous clear bits in a directory block bitmask.
20  * variable.  The first bit doesn't count as it corresponds to the block header
23 static int afs_find_contig_bits(union afs_xdr_dir_block *block, unsigned int nr_slots)  in afs_find_contig_bits()  argument
29 	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;  in afs_find_contig_bits()
30 	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;  in afs_find_contig_bits()
31 	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;  in afs_find_contig_bits()
32 	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;  in afs_find_contig_bits()
33 	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;  in afs_find_contig_bits()
34 	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;  in afs_find_contig_bits()
35 	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;  in afs_find_contig_bits()
36 	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;  in afs_find_contig_bits()
66  * Set a number of contiguous bits in the directory block bitmap.
68 static void afs_set_contig_bits(union afs_xdr_dir_block *block,  in afs_set_contig_bits()  argument
76 	before = *(u64 *)block->hdr.bitmap;  in afs_set_contig_bits()
78 	block->hdr.bitmap[0] |= (u8)(mask >> 0 * 8);  in afs_set_contig_bits()
79 	block->hdr.bitmap[1] |= (u8)(mask >> 1 * 8);  in afs_set_contig_bits()
80 	block->hdr.bitmap[2] |= (u8)(mask >> 2 * 8);  in afs_set_contig_bits()
81 	block->hdr.bitmap[3] |= (u8)(mask >> 3 * 8);  in afs_set_contig_bits()
82 	block->hdr.bitmap[4] |= (u8)(mask >> 4 * 8);  in afs_set_contig_bits()
83 	block->hdr.bitmap[5] |= (u8)(mask >> 5 * 8);  in afs_set_contig_bits()
84 	block->hdr.bitmap[6] |= (u8)(mask >> 6 * 8);  in afs_set_contig_bits()
85 	block->hdr.bitmap[7] |= (u8)(mask >> 7 * 8);  in afs_set_contig_bits()
87 	after = *(u64 *)block->hdr.bitmap;  in afs_set_contig_bits()
91  * Clear a number of contiguous bits in the directory block bitmap.
93 static void afs_clear_contig_bits(union afs_xdr_dir_block *block,  in afs_clear_contig_bits()  argument
101 	before = *(u64 *)block->hdr.bitmap;  in afs_clear_contig_bits()
103 	block->hdr.bitmap[0] &= ~(u8)(mask >> 0 * 8);  in afs_clear_contig_bits()
104 	block->hdr.bitmap[1] &= ~(u8)(mask >> 1 * 8);  in afs_clear_contig_bits()
105 	block->hdr.bitmap[2] &= ~(u8)(mask >> 2 * 8);  in afs_clear_contig_bits()
106 	block->hdr.bitmap[3] &= ~(u8)(mask >> 3 * 8);  in afs_clear_contig_bits()
107 	block->hdr.bitmap[4] &= ~(u8)(mask >> 4 * 8);  in afs_clear_contig_bits()
108 	block->hdr.bitmap[5] &= ~(u8)(mask >> 5 * 8);  in afs_clear_contig_bits()
109 	block->hdr.bitmap[6] &= ~(u8)(mask >> 6 * 8);  in afs_clear_contig_bits()
110 	block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);  in afs_clear_contig_bits()
112 	after = *(u64 *)block->hdr.bitmap;  in afs_clear_contig_bits()
116  * Scan a directory block looking for a dirent of the right name.
118 static int afs_dir_scan_block(union afs_xdr_dir_block *block, struct qstr *name,  in afs_dir_scan_block()  argument
127 	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;  in afs_dir_scan_block()
128 	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;  in afs_dir_scan_block()
129 	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;  in afs_dir_scan_block()
130 	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;  in afs_dir_scan_block()
131 	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;  in afs_dir_scan_block()
132 	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;  in afs_dir_scan_block()
133 	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;  in afs_dir_scan_block()
134 	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;  in afs_dir_scan_block()
141 		de = &block->dirents[d];  in afs_dir_scan_block()
145 		/* The block was NUL-terminated by afs_dir_check_page(). */  in afs_dir_scan_block()
160  * Initialise a new directory block.  Note that block 0 is special and contains
164 				union afs_xdr_dir_block *block, int block_num)  in afs_edit_init_block()  argument
166 	memset(block, 0, sizeof(*block));  in afs_edit_init_block()
167 	block->hdr.npages = htons(1);  in afs_edit_init_block()
168 	block->hdr.magic = AFS_DIR_MAGIC;  in afs_edit_init_block()
169 	block->hdr.bitmap[0] = 1;  in afs_edit_init_block()
172 		block->hdr.bitmap[0] = 0xff;  in afs_edit_init_block()
173 		block->hdr.bitmap[1] = 0x1f;  in afs_edit_init_block()
174 		memset(block->meta.alloc_ctrs,  in afs_edit_init_block()
176 		       sizeof(block->meta.alloc_ctrs));  in afs_edit_init_block()
198 	union afs_xdr_dir_block *meta, *block;  in afs_edit_dir_add()  local
235 	/* Find a block that has sufficient slots available.  Each VM page  in afs_edit_dir_add()
265 		block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];  in afs_edit_dir_add()
267 		_debug("block %u: %2u %3u %u",  in afs_edit_dir_add()
270 		       ntohs(block->hdr.npages),  in afs_edit_dir_add()
271 		       ntohs(block->hdr.magic));  in afs_edit_dir_add()
273 		/* Initialise the block if necessary. */  in afs_edit_dir_add()
276 			afs_edit_init_block(meta, block, b);  in afs_edit_dir_add()
286 			slot = afs_find_contig_bits(block, need_slots);  in afs_edit_dir_add()
313 	block = meta;  in afs_edit_dir_add()
321 	de = &block->dirents[slot];  in afs_edit_dir_add()
331 	afs_set_contig_bits(block, slot, need_slots);  in afs_edit_dir_add()
379 	union afs_xdr_dir_block *meta, *block;  in afs_edit_dir_remove()  local
431 		block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];  in afs_edit_dir_remove()
435 			slot = afs_dir_scan_block(block, name, b);  in afs_edit_dir_remove()
454 	de = &block->dirents[slot];  in afs_edit_dir_remove()
463 	afs_clear_contig_bits(block, slot, need_slots);  in afs_edit_dir_remove()