18  * Find a number of contiguous clear bits in a directory block bitmask.
21  * variable.  The first bit doesn't count as it corresponds to the block header
24 static int afs_find_contig_bits(union afs_xdr_dir_block *block, unsigned int nr_slots)  in afs_find_contig_bits()  argument
30 	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;  in afs_find_contig_bits()
31 	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;  in afs_find_contig_bits()
32 	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;  in afs_find_contig_bits()
33 	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;  in afs_find_contig_bits()
34 	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;  in afs_find_contig_bits()
35 	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;  in afs_find_contig_bits()
36 	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;  in afs_find_contig_bits()
37 	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;  in afs_find_contig_bits()
67  * Set a number of contiguous bits in the directory block bitmap.
69 static void afs_set_contig_bits(union afs_xdr_dir_block *block,  in afs_set_contig_bits()  argument
77 	block->hdr.bitmap[0] |= (u8)(mask >> 0 * 8);  in afs_set_contig_bits()
78 	block->hdr.bitmap[1] |= (u8)(mask >> 1 * 8);  in afs_set_contig_bits()
79 	block->hdr.bitmap[2] |= (u8)(mask >> 2 * 8);  in afs_set_contig_bits()
80 	block->hdr.bitmap[3] |= (u8)(mask >> 3 * 8);  in afs_set_contig_bits()
81 	block->hdr.bitmap[4] |= (u8)(mask >> 4 * 8);  in afs_set_contig_bits()
82 	block->hdr.bitmap[5] |= (u8)(mask >> 5 * 8);  in afs_set_contig_bits()
83 	block->hdr.bitmap[6] |= (u8)(mask >> 6 * 8);  in afs_set_contig_bits()
84 	block->hdr.bitmap[7] |= (u8)(mask >> 7 * 8);  in afs_set_contig_bits()
88  * Clear a number of contiguous bits in the directory block bitmap.
90 static void afs_clear_contig_bits(union afs_xdr_dir_block *block,  in afs_clear_contig_bits()  argument
98 	block->hdr.bitmap[0] &= ~(u8)(mask >> 0 * 8);  in afs_clear_contig_bits()
99 	block->hdr.bitmap[1] &= ~(u8)(mask >> 1 * 8);  in afs_clear_contig_bits()
100 	block->hdr.bitmap[2] &= ~(u8)(mask >> 2 * 8);  in afs_clear_contig_bits()
101 	block->hdr.bitmap[3] &= ~(u8)(mask >> 3 * 8);  in afs_clear_contig_bits()
102 	block->hdr.bitmap[4] &= ~(u8)(mask >> 4 * 8);  in afs_clear_contig_bits()
103 	block->hdr.bitmap[5] &= ~(u8)(mask >> 5 * 8);  in afs_clear_contig_bits()
104 	block->hdr.bitmap[6] &= ~(u8)(mask >> 6 * 8);  in afs_clear_contig_bits()
105 	block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);  in afs_clear_contig_bits()
109  * Get a specific block, extending the directory storage to cover it as needed.
111 static union afs_xdr_dir_block *afs_dir_get_block(struct afs_dir_iter *iter, size_t block)  in afs_dir_get_block()  argument
116 	size_t blpos = block * AFS_DIR_BLOCK_SIZE;  in afs_dir_get_block()
117 	size_t blend = (block + 1) * AFS_DIR_BLOCK_SIZE, fpos = iter->fpos;  in afs_dir_get_block()
135 	/* Search the folio queue for the folio containing the block... */  in afs_dir_get_block()
141 				/* ... and then return the mapped block. */  in afs_dir_get_block()
163  * Scan a directory block looking for a dirent of the right name.
165 static int afs_dir_scan_block(const union afs_xdr_dir_block *block, const struct qstr *name,  in afs_dir_scan_block()  argument
174 	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;  in afs_dir_scan_block()
175 	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;  in afs_dir_scan_block()
176 	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;  in afs_dir_scan_block()
177 	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;  in afs_dir_scan_block()
178 	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;  in afs_dir_scan_block()
179 	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;  in afs_dir_scan_block()
180 	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;  in afs_dir_scan_block()
181 	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;  in afs_dir_scan_block()
188 		de = &block->dirents[d];  in afs_dir_scan_block()
192 		/* The block was NUL-terminated by afs_dir_check_page(). */  in afs_dir_scan_block()
207  * Initialise a new directory block.  Note that block 0 is special and contains
211 				union afs_xdr_dir_block *block, int block_num)  in afs_edit_init_block()  argument
213 	memset(block, 0, sizeof(*block));  in afs_edit_init_block()
214 	block->hdr.npages = htons(1);  in afs_edit_init_block()
215 	block->hdr.magic = AFS_DIR_MAGIC;  in afs_edit_init_block()
216 	block->hdr.bitmap[0] = 1;  in afs_edit_init_block()
219 		block->hdr.bitmap[0] = 0xff;  in afs_edit_init_block()
220 		block->hdr.bitmap[1] = 0x1f;  in afs_edit_init_block()
221 		memset(block->meta.alloc_ctrs,  in afs_edit_init_block()
223 		       sizeof(block->meta.alloc_ctrs));  in afs_edit_init_block()
245 	union afs_xdr_dir_block *meta, *block;  in afs_edit_dir_add()  local
272 	/* Find a block that has sufficient slots available.  Each folio  in afs_edit_dir_add()
287 		block = afs_dir_get_block(&iter, b);  in afs_edit_dir_add()
288 		if (!block)  in afs_edit_dir_add()
295 		_debug("block %u: %2u %3u %u",  in afs_edit_dir_add()
298 		       ntohs(block->hdr.npages),  in afs_edit_dir_add()
299 		       ntohs(block->hdr.magic));  in afs_edit_dir_add()
301 		/* Initialise the block if necessary. */  in afs_edit_dir_add()
304 			afs_edit_init_block(meta, block, b);  in afs_edit_dir_add()
311 		slot = afs_find_contig_bits(block, iter.nr_slots);  in afs_edit_dir_add()
317 		kunmap_local(block);  in afs_edit_dir_add()
332 	block = afs_dir_get_block(&iter, 0);  in afs_edit_dir_add()
340 	de = &block->dirents[slot];  in afs_edit_dir_add()
350 	afs_set_contig_bits(block, slot, iter.nr_slots);  in afs_edit_dir_add()
361 	kunmap_local(block);  in afs_edit_dir_add()
376 	kunmap_local(block);  in afs_edit_dir_add()
396 	union afs_xdr_dir_block *meta, *block, *pblock;  in afs_edit_dir_remove()  local
436 	block = afs_dir_find_block(&iter, b);  in afs_edit_dir_remove()
437 	if (!block)  in afs_edit_dir_remove()
443 	de = &block->dirents[slot];  in afs_edit_dir_remove()
452 	afs_clear_contig_bits(block, slot, iter.nr_slots);  in afs_edit_dir_remove()
461 	kunmap_local(block);  in afs_edit_dir_remove()
511 	kunmap_local(block);  in afs_edit_dir_remove()
517 	kunmap_local(block);  in afs_edit_dir_remove()
531 	union afs_xdr_dir_block *block;  in afs_edit_dir_update_dotdot()  local
548 	/* Find a block that has sufficient slots available.  Each folio  in afs_edit_dir_update_dotdot()
552 		block = afs_dir_get_block(&iter, b);  in afs_edit_dir_update_dotdot()
553 		if (!block)  in afs_edit_dir_update_dotdot()
560 		slot = afs_dir_scan_block(block, &dotdot_name, b);  in afs_edit_dir_update_dotdot()
564 		kunmap_local(block);  in afs_edit_dir_update_dotdot()
574 	de = &block->dirents[slot];  in afs_edit_dir_update_dotdot()
581 	kunmap_local(block);  in afs_edit_dir_update_dotdot()
590 	kunmap_local(block);  in afs_edit_dir_update_dotdot()