# This is a BitKeeper generated patch for the following project: # Project Name: Linux kernel tree # This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas: # ChangeSet 1.590 -> 1.591 # fs/reiserfs/file.c 1.9 -> 1.10 # fs/reiserfs/inode.c 1.36 -> 1.37 # include/linux/reiserfs_fs.h 1.22 -> 1.23 # fs/reiserfs/super.c 1.22 -> 1.23 # include/linux/reiserfs_fs_sb.h 1.12 -> 1.13 # fs/reiserfs/bitmap.c 1.16 -> 1.17 # # The following is the BitKeeper ChangeSet Log # -------------------------------------------- # 02/09/09 green@angband.namesys.com 1.591 # Implemented reiserfs_file_write(), to write large amount of data at once into files on reiserfs volumes which should boost write speed somewhat and also should be somewhat more SMP friendly. # -------------------------------------------- # diff -Nru a/fs/reiserfs/bitmap.c b/fs/reiserfs/bitmap.c --- a/fs/reiserfs/bitmap.c Mon Sep 9 09:28:34 2002 +++ b/fs/reiserfs/bitmap.c Mon Sep 9 09:28:34 2002 @@ -738,7 +738,7 @@ int rest = amount_needed; int nr_allocated; - while (rest > 0) { + while (rest > 0 && start <= finish) { nr_allocated = scan_bitmap (hint->th, &start, finish, 1, rest + prealloc_size, !hint->formatted_node, hint->block); @@ -884,7 +884,9 @@ if ( !blocks ) return; + spin_lock(&sb->u.reiserfs_sb.bitmap_lock); sb->u.reiserfs_sb.reserved_blocks += blocks; + spin_unlock(&sb->u.reiserfs_sb.bitmap_lock); } /* Unreserve @blocks amount of blocks in fs pointed by @sb */ @@ -901,6 +903,22 @@ if ( !blocks ) return; + spin_lock(&sb->u.reiserfs_sb.bitmap_lock); sb->u.reiserfs_sb.reserved_blocks -= blocks; RFALSE( sb->u.reiserfs_sb.reserved_blocks < 0, "amount of blocks reserved became zero?"); + spin_unlock(&sb->u.reiserfs_sb.bitmap_lock); +} + +/* This function estimates how much pages we will be able to write to FS + used for reiserfs_file_write() purposes for now. */ +int reiserfs_can_fit_pages ( struct super_block *sb /* superblock of filesystem + to estimate space */ ) +{ + unsigned long space; + + spin_lock(&sb->u.reiserfs_sb.bitmap_lock); + space = (SB_FREE_BLOCKS(sb) - sb->u.reiserfs_sb.reserved_blocks) / ( PAGE_CACHE_SIZE/sb->s_blocksize); + spin_unlock(&sb->u.reiserfs_sb.bitmap_lock); + + return space; } diff -Nru a/fs/reiserfs/file.c b/fs/reiserfs/file.c --- a/fs/reiserfs/file.c Mon Sep 9 09:28:34 2002 +++ b/fs/reiserfs/file.c Mon Sep 9 09:28:34 2002 @@ -6,6 +6,9 @@ #include #include #include +#include +#include +#include /* ** We pack the tails of files on file close, not at the time they are written. @@ -129,9 +132,1080 @@ return error ; } +/* this function from inode.c would be used here, too */ +extern void restart_transaction(struct reiserfs_transaction_handle *th, + struct inode *inode, struct path *path); + +/* I really do not want to play with memory shortage right now, so + to simplify the code, we are not going to write more than this much pages at + a time. This still should considerably improve performance compared to 4k + at a time case. */ +#define REISERFS_WRITE_PAGES_AT_A_TIME 32 + +/* Allocates blocks for a file to fulfil write request. + Maps all unmapped but prepared pages from the list. + Updates metadata with newly allocated blocknumbers as needed */ +int reiserfs_allocate_blocks_for_region( + struct inode *inode, /* Inode we work with */ + loff_t pos, /* Writing position */ + int num_pages, /* number of pages write going + to touch */ + int write_bytes, /* amount of bytes to write */ + struct page **prepared_pages, /* array of + prepared pages + */ + int blocks_to_allocate /* Amount of blocks we + need to allocate to + fit the data into file + */ + ) +{ + struct cpu_key key; // cpu key of item that we are going to deal with + struct item_head *ih; // pointer to item head that we are going to deal with + struct buffer_head *bh; // Buffer head that contains items that we are going to deal with + struct reiserfs_transaction_handle th; // transaction handle for transaction we are going to create. + __u32 * item; // pointer to item we are going to deal with + INITIALIZE_PATH(path); // path to item, that we are going to deal with. + b_blocknr_t allocated_blocks[blocks_to_allocate]; // Pointer to a place where allocated blocknumbers would be stored. Right now statically allocated, later that will change. + reiserfs_blocknr_hint_t hint; // hint structure for block allocator. + size_t res; // return value of various functions that we call. + int curr_block; // current block used to keep track of unmapped blocks. + int i; // loop counter + int itempos; // position in item + unsigned int from = (pos & (PAGE_CACHE_SIZE - 1)); // writing position in + // first page + unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; /* last modified byte offset in last page */ + __u64 hole_size ; // amount of blocks for a file hole, if it needed to be created. + int modifying_this_item = 0; // Flag for items traversal code to keep track + // of the fact that we already prepared + // current block for journal + + + RFALSE(!blocks_to_allocate, "green-9004: tried to allocate zero blocks?"); + + /* First we compose a key to point at the writing position, we want to do + that outside of any locking region. */ + make_cpu_key (&key, inode, pos+1, TYPE_ANY, 3/*key length*/); + + /* If we came here, it means we absolutely need to open a transaction, + since we need to allocate some blocks */ + lock_kernel(); // Journaling stuff and we need that. + journal_begin(&th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1); // Wish I know if this number enough + reiserfs_update_inode_transaction(inode) ; + + /* Look for the in-tree position of our write, need path for block allocator */ + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR ) { + res = -EIO; + goto error_exit; + } + + /* Allocate blocks */ + /* First fill in "hint" structure for block allocator */ + hint.th = &th; // transaction handle. + hint.path = &path; // Path, so that block allocator can determine packing locality or whatever it needs to determine. + hint.inode = inode; // Inode is needed by block allocator too. + hint.search_start = 0; // We have no hint on where to search free blocks for block allocator. + hint.key = key.on_disk_key; // on disk key of file. + hint.block = inode->i_blocks/(inode->i_sb->s_blocksize/512); // Number of disk blocks this file occupies already. + hint.formatted_node = 0; // We are allocating blocks for unformatted node. + hint.preallocate = 0; // We do not do any preallocation for now. + + /* Call block allocator to allocate blocks */ + res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate); + if ( res != CARRY_ON ) { + if ( res == NO_DISK_SPACE ) { + /* We flush the transaction in case of no space. This way some + blocks might become free */ + SB_JOURNAL(inode->i_sb)->j_must_wait = 1; + restart_transaction(&th, inode, &path); + + /* We might have scheduled, so search again */ + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR ) { + res = -EIO; + goto error_exit; + } + + /* update changed info for hint structure. */ + res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate); + if ( res != CARRY_ON ) { + res = -ENOSPC; + pathrelse(&path); + goto error_exit; + } + } else { + res = -ENOSPC; + pathrelse(&path); + goto error_exit; + } + } + +#ifdef __BIG_ENDIAN + // Too bad, I have not found any way to convert a given region from + // cpu format to little endian format + { + int i; + for ( i = 0; i < blocks_to_allocate ; i++) + allocated_blocks[i]=cpu_to_le32(allocated_blocks[i]); + } +#endif + + /* Blocks allocating well might have scheduled and tree might have changed, + let's search the tree again */ + /* find where in the tree our write should go */ + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR ) { + res = -EIO; + goto error_exit_free_blocks; + } + + bh = get_last_bh( &path ); // Get a bufferhead for last element in path. + ih = get_ih( &path ); // Get a pointer to last item head in path. + item = get_item( &path ); // Get a pointer to last item in path + + /* Let's see what we have found */ + if ( res != POSITION_FOUND ) { /* position not found, this means that we + might need to append file with holes + first */ + // Since we are writing past the file's end, we need to find out if + // there is a hole that needs to be inserted before our writing + // position, and how many blocks it is going to cover (we need to + // populate pointers to file blocks representing the hole with zeros) + + hole_size = (pos + 1 - (le_key_k_offset( get_inode_item_key_version(inode), &(ih->ih_key))+op_bytes_number(ih, inode->i_sb->s_blocksize))) >> inode->i_sb->s_blocksize_bits; + + if ( hole_size > 0 ) { + int to_paste = min_t(__u64, hole_size, MAX_ITEM_LEN(inode->i_sb->s_blocksize)/UNFM_P_SIZE ); // How much data to insert first time. + /* area filled with zeroes, to supply as list of zero blocknumbers + We allocate it outside of loop just in case loop would spin for + several iterations. */ + char *zeros = kmalloc(to_paste*UNFM_P_SIZE, GFP_ATOMIC); // We cannot insert more than MAX_ITEM_LEN bytes anyway. + if ( !zeros ) { + res = -ENOMEM; + goto error_exit_free_blocks; + } + memset ( zeros, 0, to_paste*UNFM_P_SIZE); + do { + to_paste = min_t(__u64, hole_size, MAX_ITEM_LEN(inode->i_sb->s_blocksize)/UNFM_P_SIZE ); + if ( is_indirect_le_ih(ih) ) { + /* Ok, there is existing indirect item already. Need to append it */ + /* Calculate position past inserted item */ + make_cpu_key( &key, inode, le_key_k_offset( get_inode_item_key_version(inode), &(ih->ih_key)) + op_bytes_number(ih, inode->i_sb->s_blocksize), TYPE_INDIRECT, 3); + res = reiserfs_paste_into_item( &th, &path, &key, (char *)zeros, UNFM_P_SIZE*to_paste); + if ( res ) { + kfree(zeros); + goto error_exit_free_blocks; + } + } else if ( is_statdata_le_ih(ih) ) { + /* No existing item, create it */ + /* item head for new item */ + struct item_head ins_ih; + + /* create a key for our new item */ + make_cpu_key( &key, inode, 1, TYPE_INDIRECT, 3); + + /* Create new item head for our new item */ + make_le_item_head (&ins_ih, &key, key.version, 1, + TYPE_INDIRECT, to_paste*UNFM_P_SIZE, + 0 /* free space */); + + /* Find where such item should live in the tree */ + res = search_item (inode->i_sb, &key, &path); + if ( res != ITEM_NOT_FOUND ) { + /* item should not exist, otherwise we have error */ + if ( res != -ENOSPC ) { + reiserfs_warning ("green-9008: search_by_key (%K) returned %d\n", + &key, res); + } + res = -EIO; + kfree(zeros); + goto error_exit_free_blocks; + } + res = reiserfs_insert_item( &th, &path, &key, &ins_ih, (char *)zeros); + } else { + reiserfs_panic(inode->i_sb, "green-9011: Unexpected key type %K\n", &key); + } + if ( res ) { + kfree(zeros); + goto error_exit_free_blocks; + } + /* Now we want to check if transaction is too full, and if it is + we restart it. This will also free the path. */ + if (journal_transaction_should_end(&th, th.t_blocks_allocated)) + restart_transaction(&th, inode, &path); + + /* Well, need to recalculate path and stuff */ + set_cpu_key_k_offset( &key, cpu_key_k_offset(&key) + to_paste * inode->i_sb->s_blocksize ); + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR ) { + res = -EIO; + kfree(zeros); + goto error_exit_free_blocks; + } + bh=get_last_bh(&path); + ih=get_ih(&path); + item = get_item(&path); + hole_size -= to_paste; + } while ( hole_size ); + kfree(zeros); + } + } + + // Go through existing indirect items first + // replace all zeroes with blocknumbers from list + // Note that if no corresponding item was found, by previous search, + // it means there are no existing in-tree representation for file area + // we are going to overwrite, so there is nothing to scan through for holes. + for ( curr_block = 0, itempos = path.pos_in_item ; curr_block < blocks_to_allocate && res == POSITION_FOUND ; ) { + + if ( itempos >= ih_item_len(ih)/UNFM_P_SIZE ) { + /* We run out of data in this indirect item, let's look for another + one. */ + /* First if we are already modifying current item, log it */ + if ( modifying_this_item ) { + journal_mark_dirty (&th, inode->i_sb, bh); + modifying_this_item = 0; + } + /* Then set the key to look for a new indirect item (offset of old + item is added to old item length */ + set_cpu_key_k_offset( &key, le_key_k_offset( get_inode_item_key_version(inode), &(ih->ih_key)) + op_bytes_number(ih, inode->i_sb->s_blocksize)); + /* Search ofor position of new key in the tree. */ + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR) { + res = -EIO; + goto error_exit_free_blocks; + } + bh=get_last_bh(&path); + ih=get_ih(&path); + item = get_item(&path); + itempos = path.pos_in_item; + continue; // loop to check all kinds of conditions and so on. + } + /* Ok, we have correct position in item now, so let's see if it is + representing file hole (blocknumber is zero) and fill it if needed */ + if ( !item[itempos] ) { + /* Ok, a hole. Now we need to check if we already prepared this + block to be journaled */ + while ( !modifying_this_item ) { // loop until succeed + /* Well, this item is not journaled yet, so we must prepare + it for journal first, before we can change it */ + struct item_head tmp_ih; // We copy item head of found item, + // here to detect if fs changed under + // us while we were preparing for + // journal. + int fs_gen; // We store fs generation here to find if someone + // changes fs under our feet + + copy_item_head (&tmp_ih, ih); // Remember itemhead + fs_gen = get_generation (inode->i_sb); // remember fs generation + reiserfs_prepare_for_journal(inode->i_sb, bh, 1); // Prepare a buffer within which indirect item is stored for changing. + if (fs_changed (fs_gen, inode->i_sb) && item_moved (&tmp_ih, &path)) { + // Sigh, fs was changed under us, we need to look for new + // location of item we are working with + + /* unmark prepaerd area as journaled and search for it's + new position */ + reiserfs_restore_prepared_buffer(inode->i_sb, bh); + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR) { + res = -EIO; + goto error_exit_free_blocks; + } + bh=get_last_bh(&path); + ih=get_ih(&path); + item = get_item(&path); + // Itempos is still the same + continue; + } + modifying_this_item = 1; + } + item[itempos] = allocated_blocks[curr_block]; // Assign new block + curr_block++; + } + itempos++; + } + + if ( modifying_this_item ) { // We need to log last-accessed block, if it + // was modified, but not logged yet. + journal_mark_dirty (&th, inode->i_sb, bh); + } + + if ( curr_block < blocks_to_allocate ) { + // Oh, well need to append to indirect item, or to create indirect item + // if there weren't any + if ( is_indirect_le_ih(ih) ) { + // Existing indirect item - append. First calculate key for append + // position. We do not need to recalculate path as it should + // already point to correct place. + make_cpu_key( &key, inode, le_key_k_offset( get_inode_item_key_version(inode), &(ih->ih_key)) + op_bytes_number(ih, inode->i_sb->s_blocksize), TYPE_INDIRECT, 3); + res = reiserfs_paste_into_item( &th, &path, &key, (char *)(allocated_blocks+curr_block), UNFM_P_SIZE*(blocks_to_allocate-curr_block)); + if ( res ) { + goto error_exit_free_blocks; + } + } else if (is_statdata_le_ih(ih) ) { + // Last found item was statdata. That means we need to create indirect item. + struct item_head ins_ih; /* itemhead for new item */ + + /* create a key for our new item */ + make_cpu_key( &key, inode, 1, TYPE_INDIRECT, 3); // Position one, + // because that's + // where first + // indirect item + // begins + /* Create new item head for our new item */ + make_le_item_head (&ins_ih, &key, key.version, 1, TYPE_INDIRECT, + (blocks_to_allocate-curr_block)*UNFM_P_SIZE, + 0 /* free space */); + /* Find where such item should live in the tree */ + res = search_item (inode->i_sb, &key, &path); + if ( res != ITEM_NOT_FOUND ) { + /* Well, if we have found such item already, or some error + occured, we need to warn user and return error */ + if ( res != -ENOSPC ) { + reiserfs_warning ("green-9009: search_by_key (%K) returned %d\n", + &key, res); + } + res = -EIO; + goto error_exit_free_blocks; + } + /* Insert item into the tree with the data as its body */ + res = reiserfs_insert_item( &th, &path, &key, &ins_ih, (char *)(allocated_blocks+curr_block)); + } else { + reiserfs_panic(inode->i_sb, "green-9010: unexpected item type for key %K\n",&key); + } + } + + /* Now the final thing, if we have grew the file, we must update it's size*/ + if ( pos + write_bytes > inode->i_size) { + inode->i_size = pos + write_bytes; // Set new size + } + + /* Amount of on-disk blocks used by file have changed, update it */ + inode->i_blocks += blocks_to_allocate * (inode->i_sb->s_blocksize / 512); + reiserfs_update_sd(&th, inode); // And update on-disk metadata + // finish all journal stuff now, We are not going to play with metadata + // anymore. + pathrelse(&path); + journal_end(&th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1); + unlock_kernel(); + + // go through all the pages/buffers and map the buffers to newly allocated + // blocks (so that system knows where to write these pages later). + curr_block = 0; + for ( i = 0; i < num_pages ; i++ ) { + struct page *page=prepared_pages[i]; //current page + struct buffer_head *head = page->buffers; // first buffer for a page + int block_start, block_end; // in-page offsets for buffers. + + if (!page->buffers) + reiserfs_panic(inode->i_sb, "green-9005: No buffers for prepared page???"); + + /* For each buffer in page */ + for(bh = head, block_start = 0; bh != head || !block_start; + block_start=block_end, bh = bh->b_this_page) { + if (!bh) + reiserfs_panic(inode->i_sb, "green-9006: Allocated but absent buffer for a page?"); + block_end = block_start+inode->i_sb->s_blocksize; + if (i == 0 && block_end <= from ) + /* if this buffer is before requested data to map, skip it */ + continue; + if (i == num_pages - 1 && block_start >= to) + /* If this buffer is after requested data to map, abort + processing of current page */ + break; + + if ( !buffer_mapped(bh) ) { // Ok, unmapped buffer, need to map it + bh->b_dev = inode->i_dev; + bh->b_blocknr = le32_to_cpu(allocated_blocks[curr_block]); + set_bit(BH_Mapped, &bh->b_state); + curr_block++; + } + } + } + + RFALSE( curr_block > blocks_to_allocate, "green-9007: Used too many blocks? weird"); + + return 0; + +// Need to deal with transaction here. +error_exit_free_blocks: + pathrelse(&path); + // free blocks + for( i = 0; i < blocks_to_allocate; i++ ) + reiserfs_free_block( &th, le32_to_cpu(allocated_blocks[i])); + +error_exit: + journal_end(&th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1); + unlock_kernel(); + + return res; +} + +/* Unlock pages prepared by reiserfs_prepare_file_region_for_write */ +void reiserfs_unprepare_pages(struct page **prepared_pages, /* list of locked pages */ + int num_pages /* amount of pages */) { + int i; // loop counter + + for (i=0; i < num_pages ; i++) { + struct page *page = prepared_pages[i]; + + try_to_free_buffers(page,0); + kunmap(page); + UnlockPage(page); + page_cache_release(page); + } +} + +/* This function will copy data from userspace to specified pages within + supplied byte range */ +int reiserfs_copy_from_user_to_file_region( + loff_t pos, /* In-file position */ + int num_pages, /* Number of pages affected */ + int write_bytes, /* Amount of bytes to write */ + struct page **prepared_pages, /* pointer to + array to + prepared pages + */ + const char *buf /* Pointer to user-supplied + data*/ + ) +{ + long page_fault=0; // status of copy_from_user. + int i; // loop counter. + int offset; // offset in page + + for ( i = 0, offset = (pos & (PAGE_CACHE_SIZE-1)); i < num_pages ; i++,offset=0) { + int count = min_t(int,PAGE_CACHE_SIZE-offset,write_bytes); // How much of bytes to write to this page + struct page *page=prepared_pages[i]; // Current page we process. + + /* Bring in the user page. We need to do it to fight some deadlocks + with copying the page to itself and page being inaccessible at + the same time.*/ + { volatile unsigned char dummy; + __get_user(dummy, buf); + __get_user(dummy, buf+count-1); + /* We do getuser for beginning and ending of the region just because + userdata may be not page aligned, and therefore data that will + go into one page of file may be splitted onto two actual pages + in userspace */ + } + + /* Copy data from userspace to the current page */ + page_fault = __copy_from_user(page_address(page)+offset, buf, count); // Copy the data. + /* Flush processor's dcache for this page */ + flush_dcache_page(page); + buf+=count; + write_bytes-=count; + + if (page_fault) + break; // Was there a fault? abort. + } + + return page_fault?-EFAULT:0; +} + + + +/* Submit pages for write. This was separated from actual file copying + because we might want to allocate block numbers in-between. + This function assumes that caller will adjust file size to correct value. */ +int reiserfs_submit_file_region_for_write( + loff_t pos, /* Writing position offset */ + int num_pages, /* Number of pages to write */ + int write_bytes, /* number of bytes to write */ + struct page **prepared_pages /* list of pages */ + ) +{ + int status; // return status of block_commit_write. + int retval = 0; // Return value we are going to return. + int i; // loop counter + int offset; // Writing offset in page. + + for ( i = 0, offset = (pos & (PAGE_CACHE_SIZE-1)); i < num_pages ; i++,offset=0) { + int count = min_t(int,PAGE_CACHE_SIZE-offset,write_bytes); // How much of bytes to write to this page + struct page *page=prepared_pages[i]; // Current page we process. + + status = block_commit_write(page, offset, offset+count); // Note this also kunmaps kmapped page. + if ( status ) + retval = status; // To not overcomplicate matters We are going to + // submit all the pages even if there was error. + // we only remember error status to report it on + // exit. + write_bytes-=count; + SetPageReferenced(page); + UnlockPage(page); // We unlock the page as it was locked by earlier call + // to grab_cache_page + page_cache_release(page); + } + return retval; +} + +/* Look if passed writing region is going to touch file's tail + (if it is present). And if it is, convert the tail to unformatted node */ +int reiserfs_check_for_tail_and_convert( struct inode *inode, /* inode to deal with */ + loff_t pos, /* Writing position */ + int write_bytes /* amount of bytes to write */ + ) +{ + INITIALIZE_PATH(path); // needed for search_for_position + struct cpu_key key; // Key that would represent last touched writing byte. + struct item_head *ih; // item header of found block; + int res; // Return value of various functions we call. + int cont_expand_offset; // We will put offset for generic_cont_expand here + // This can be int just because tails are created + // only for small files. + +/* this embodies a dependency on a particular tail policy */ + if ( inode->i_size >= inode->i_sb->s_blocksize*4 ) { + /* such a big files do not have tails, so we won't bother ourselves + to look for tails, simply return */ + return 0; + } + + lock_kernel(); + /* find the item containing the last byte to be written, or if + * writing past the end of the file then the last item of the + * file (and then we check its type). */ + make_cpu_key (&key, inode, pos+write_bytes+1, TYPE_ANY, 3/*key length*/); + res = search_for_position_by_key(inode->i_sb, &key, &path); + if ( res == IO_ERROR ) { + unlock_kernel(); + return -EIO; + } + ih = get_ih(&path); + res = 0; + if ( is_direct_le_ih(ih) ) { + /* Ok, closest item is file tail (tails are stored in "direct" + * items), so we need to unpack it. */ + /* To not overcomplicate matters, we just call generic_cont_expand + which will in turn call other stuff and finally will boil down to + reiserfs_get_block() that would do necessary conversion. */ + cont_expand_offset = le_key_k_offset(get_inode_item_key_version(inode), &(ih->ih_key)); + pathrelse(&path); + res = generic_cont_expand( inode, cont_expand_offset); + } else + pathrelse(&path); + + unlock_kernel(); + return res; +} + +/* This functions kmaps and locks pages starting from @pos for @inode. + @num_pages pages are locked and stored in + @prepared_pages array. Also buffers are allocated for these pages. + First and last page of the region is read if it is overwritten only + partially. If last page did not exist before write (file hole or file + append), it is zeroed, then. + Returns number of unallocated blocks that should be allocated to cover + new file data.*/ +int reiserfs_prepare_file_region_for_write( + struct inode *inode /* Inode of the file */, + loff_t pos, /* position in the file */ + int num_pages, /* number of pages to + prepare */ + int write_bytes, /* Amount of bytes to be + overwritten from + @pos */ + struct page **prepared_pages /* pointer to array + where to store + prepared pages */ + ) +{ + int res=0; // Return values of different functions we call. + unsigned long index = pos >> PAGE_CACHE_SHIFT; // Offset in file in pages. + int from = (pos & (PAGE_CACHE_SIZE - 1)); // Writing offset in first page + int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; + /* offset of last modified byte in last + page */ + struct address_space *mapping = inode->i_mapping; // Pages are mapped here. + int i; // Simple counter + int blocks = 0; /* Return value (blocks that should be allocated) */ + struct buffer_head *bh, *head; // Current bufferhead and first bufferhead + // of a page. + unsigned block_start, block_end; // Starting and ending offsets of current + // buffer in the page. + struct buffer_head *wait[2], **wait_bh=wait; // Buffers for page, if + // Page appeared to be not up + // to date. Note how we have + // at most 2 buffers, this is + // because we at most may + // partially overwrite two + // buffers for one page. One at // the beginning of write area + // and one at the end. + // Everything inthe middle gets // overwritten totally. + + struct cpu_key key; // cpu key of item that we are going to deal with + struct item_head *ih = NULL; // pointer to item head that we are going to deal with + struct buffer_head *itembuf=NULL; // Buffer head that contains items that we are going to deal with + INITIALIZE_PATH(path); // path to item, that we are going to deal with. + __u32 * item=0; // pointer to item we are going to deal with + + + if ( num_pages < 1 ) { + reiserfs_warning("green-9001: reiserfs_prepare_file_region_for_write called with zero number of pages to process\n"); + return -EFAULT; + } + + /* We have 2 loops for pages. In first loop we grab and lock the pages, so + that nobody would touch these until we release the pages. Then + we'd start to deal with mapping buffers to blocks. */ + for ( i = 0; i < num_pages; i++) { + prepared_pages[i] = grab_cache_page(mapping, index + i); // locks the page + if ( !prepared_pages[i]) { + res = -ENOMEM; + goto failed_page_grabbing; + } + kmap(prepared_pages[i]); // MAp the page in conventional RAM. + if (!prepared_pages[i]->buffers) + create_empty_buffers(prepared_pages[i], inode->i_dev, inode->i_sb->s_blocksize); + } + + /* Let's count amount of blocks for a case where all the blocks + overwritten are new (we will substract already allocated blocks later)*/ + if ( num_pages > 2 ) + /* These are full-overwritten pages so we count all the blocks in + these pages are counted as needed to be allocated */ + blocks = (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize) * (num_pages - 2); + + /* count blocks needed for first page (possibly partially written) */ + blocks += ((PAGE_CACHE_SIZE - from) >> inode->i_sb->s_blocksize_bits) + + !!(from & (inode->i_sb->s_blocksize-1)); /* roundup */ + + /* Now we account for last page. If last page == first page (we + overwrite only one page), we substract all the blocks past the + last writing position in a page out of already calculated number + of blocks */ + blocks += (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize) * (num_pages > 1) - + ((PAGE_CACHE_SIZE - to) >> inode->i_sb->s_blocksize_bits); + /* Note how we do not roundup here since partial blocks still + should be allocated */ + + /* Now if all the write area lies past the file end, no point in + maping blocks, since there is none, so we just zero out remaining + parts of first and last pages in write area (if needed) */ + if ( (pos & ~(PAGE_CACHE_SIZE - 1)) > inode->i_size ) { + if ( from != 0 ) {/* First page needs to be partially zeroed */ + memset(page_address(prepared_pages[0]), 0, from); + SetPageUptodate(prepared_pages[0]); + } + if ( to != PAGE_CACHE_SIZE ) { /* Last page needs to be partially zeroed */ + memset(page_address(prepared_pages[num_pages-1])+to, 0, PAGE_CACHE_SIZE - to); + SetPageUptodate(prepared_pages[num_pages-1]); + } + + /* Since all blocks are new - use already calculated value */ + return blocks; + } + + /* Well, since we write somewhere into the middle of a file, there is + possibility we are writing over some already allocated blocks, so + let's map these blocks and substract number of such blocks out of blocks + we need to allocate (calculated above) */ + /* Mask write position to start on blocksize, we do it out of the + loop for performance reasons */ + pos &= ~(inode->i_sb->s_blocksize - 1); + /* Set cpu key to the starting position in a file (on left block boundary)*/ + make_cpu_key (&key, inode, 1 + ((pos) & ~(inode->i_sb->s_blocksize - 1)), TYPE_ANY, 3/*key length*/); + + lock_kernel(); // We need that for at least search_by_key() + for ( i = 0; i < num_pages ; i++ ) { + int item_pos=-1; /* Position in indirect item */ + + head = prepared_pages[i]->buffers; + /* For each buffer in the page */ + for(bh = head, block_start = 0; bh != head || !block_start; + block_start=block_end, bh = bh->b_this_page) { + if (!bh) + reiserfs_panic(inode->i_sb, "green-9002: Allocated but absent buffer for a page?"); + /* Find where this buffer ends */ + block_end = block_start+inode->i_sb->s_blocksize; + if (i == 0 && block_end <= from ) + /* if this buffer is before requested data to map, skip it*/ + continue; + + if (i == num_pages - 1 && block_start >= to) { + /* If this buffer is after requested data to map, abort + processing of current page */ + break; + } + + if ( buffer_mapped(bh) && bh->b_blocknr !=0 ) { + /* This is optimisation for a case where buffer is mapped + and have blocknumber assigned. In case significant amount + of such buffers are present, we may avoid some amount + of search_by_key calls. + Probably it would be possible to move parts of this code + out of BKL, but I afraid that would overcomplicate code + without any noticeable benefit. + */ + item_pos++; + /* Update the key */ + set_cpu_key_k_offset( &key, cpu_key_k_offset(&key) + inode->i_sb->s_blocksize); + blocks--; // Decrease the amount of blocks that need to be + // allocated + continue; // Go to the next buffer + } + + if ( !itembuf || /* if first iteration */ + item_pos >= ih_item_len(ih)/UNFM_P_SIZE) + { /* or if we progressed past the + current unformatted_item */ + /* Try to find next item */ + res = search_for_position_by_key(inode->i_sb, &key, &path); + /* Abort if no more items */ + if ( res != POSITION_FOUND ) + break; + + /* Update information about current indirect item */ + itembuf = get_last_bh( &path ); + ih = get_ih( &path ); + item = get_item( &path ); + item_pos = path.pos_in_item; + + RFALSE( !is_indirect_le_ih (ih), "green-9003: indirect item expected"); + } + + /* See if there is some block associated with the file + at that position, map the buffer to this block */ + if ( get_block_num(item,item_pos) ) { + bh->b_dev = inode->i_dev; + bh->b_blocknr = get_block_num(item,item_pos); + set_bit(BH_Mapped, &bh->b_state); + blocks--; // Decrease the amount of blocks that need to be + // allocated + } + item_pos++; + /* Update the key */ + set_cpu_key_k_offset( &key, cpu_key_k_offset(&key) + inode->i_sb->s_blocksize); + } + } + pathrelse(&path); // Free the path + unlock_kernel(); + + /* Now zero out unmappend buffers for the first and last pages of + write area or issue read requests if page is mapped. */ + /* First page, see if it is not uptodate */ + if ( !Page_Uptodate(prepared_pages[0]) ) { + head = prepared_pages[0]->buffers; + + /* For wach buffer in page */ + for(bh = head, block_start = 0; bh != head || !block_start; + block_start=block_end, bh = bh->b_this_page) { + + if (!bh) + reiserfs_panic(inode->i_sb, "green-9002: Allocated but absent buffer for a page?"); + /* Find where this buffer ends */ + block_end = block_start+inode->i_sb->s_blocksize; + if ( block_end <= from ) + /* if this buffer is before requested data to map, skip it*/ + continue; + if ( block_start < from ) { /* Aha, our partial buffer */ + if ( buffer_mapped(bh) ) { /* If it is mapped, we need to + issue READ request for it to + not loose data */ + ll_rw_block(READ, 1, &bh); + *wait_bh++=bh; + } else { /* Not mapped, zero it */ + memset(page_address(prepared_pages[0])+block_start, 0, from-block_start); + set_bit(BH_Uptodate, &bh->b_state); + } + } + } + } + + /* Last page, see if it is not uptodate, or if the last page is past the end of the file. */ + if ( !Page_Uptodate(prepared_pages[num_pages-1]) || + ((pos+write_bytes)>>PAGE_CACHE_SHIFT) > (inode->i_size>>PAGE_CACHE_SHIFT) ) { + head = prepared_pages[num_pages-1]->buffers; + + /* for each buffer in page */ + for(bh = head, block_start = 0; bh != head || !block_start; + block_start=block_end, bh = bh->b_this_page) { + + if (!bh) + reiserfs_panic(inode->i_sb, "green-9002: Allocated but absent buffer for a page?"); + /* Find where this buffer ends */ + block_end = block_start+inode->i_sb->s_blocksize; + if ( block_start >= to ) + /* if this buffer is after requested data to map, skip it*/ + break; + if ( block_end > to ) { /* Aha, our partial buffer */ + if ( buffer_mapped(bh) ) { /* If it is mapped, we need to + issue READ request for it to + not loose data */ + ll_rw_block(READ, 1, &bh); + *wait_bh++=bh; + } else { /* Not mapped, zero it */ + memset(page_address(prepared_pages[num_pages-1])+to, 0, block_end-to); + set_bit(BH_Uptodate, &bh->b_state); + } + } + } + } + + /* Wait for read requests we made to happen, if necessary */ + while(wait_bh > wait) { + wait_on_buffer(*--wait_bh); + if (!buffer_uptodate(*wait_bh)) { + res = -EIO; + goto failed_read; + } + } + + return blocks; +failed_page_grabbing: + num_pages = i; +failed_read: + reiserfs_unprepare_pages(prepared_pages, num_pages); + return res; +} + +/* Write @count bytes at position @ppos in a file indicated by @file + from the buffer @buf. + + generic_file_write() is only appropriate for filesystems that are not seeking to optimize performance and want + something simple that works. It is not for serious use by general purpose filesystems, excepting the one that it was + written for (ext2/3). This is for several reasons: + + * It has no understanding of any filesystem specific optimizations. + + * It enters the filesystem repeatedly for each page that is written. + + * It depends on reiserfs_get_block() function which if implemented by reiserfs performs costly search_by_key + * operation for each page it is supplied with. By contrast reiserfs_file_write() feeds as much as possible at a time + * to reiserfs which allows for fewer tree traversals. + + * Each indirect pointer insertion takes a lot of cpu, because it involves memory moves inside of blocks. + + * Asking the block allocation code for blocks one at a time is slightly less efficient. + + All of these reasons for not using only generic file write were understood back when reiserfs was first miscoded to + use it, but we were in a hurry to make code freeze, and so it couldn't be revised then. This new code should make + things right finally. + + Future Features: providing search_by_key with hints. + +*/ +ssize_t reiserfs_file_write( struct file *file, /* the file we are going to write into */ + const char *buf, /* pointer to user supplied data +(in userspace) */ + size_t count, /* amount of bytes to write */ + loff_t *ppos /* pointer to position in file that we start writing at. Should be updated to + * new current position before returning. */ ) +{ + size_t already_written = 0; // Number of bytes already written to the file. + loff_t pos; // Current position in the file. + size_t res; // return value of various functions that we call. + unsigned long limit = current->rlim[RLIMIT_FSIZE].rlim_cur; // Current filesize limit + struct inode *inode = file->f_dentry->d_inode; // Inode of the file that we are writing to. + struct page * prepared_pages[REISERFS_WRITE_PAGES_AT_A_TIME]; + /* To simplify coding at this time, we store + locked pages in array for now */ + if ( count <= PAGE_CACHE_SIZE || file->f_flags & O_DIRECT) + return generic_file_write(file, buf, count, ppos); + + if ( (ssize_t) count < 0 ) + return -EINVAL; + + if (!access_ok(VERIFY_READ, buf, count)) + return -EFAULT; + + down(&inode->i_sem); // locks the entire file for just us + + // We are going to duplicate a lot of generic_file_write checks here + // for now. I do not have any good idea on how to avoid these now. + + res = -EINVAL; + if ( *ppos < 0) + goto out; + + res = file->f_error; + if ( res ) { + file->f_error = 0; + goto out; + } + + if (file->f_flags & O_APPEND) + pos=inode->i_size; + else + pos=*ppos; + + res = -EFBIG; + if ( limit != RLIM_INFINITY) { + if (pos >= limit) { + send_sig(SIGXFSZ, current, 0); + goto out; + } + if ( pos > 0xFFFFFFFFULL || count > limit - (u32)pos) { + count = limit - (u32)pos; + } + } + + // LFS + if ( pos + count > MAX_NON_LFS && !(file->f_flags & O_LARGEFILE) ) { + if ( pos >= MAX_NON_LFS ) { + send_sig(SIGXFSZ, current, 0); + goto out; + } + if ( count > MAX_NON_LFS - (u32)pos ) { + count = MAX_NON_LFS - (u32)pos; + } + } + + // Check we are not going to exceed block limit + if ( pos >= inode->i_sb->s_maxbytes) { + if ( count || pos > inode->i_sb->s_maxbytes) { + send_sig(SIGXFSZ, current, 0); + goto out; + } + // zero length writes are ok. + } + + res = 0; + if ( count == 0 ) + goto out; + + remove_suid(inode); + /* Mark inode dirty only in case times are actually changed. + This is to speed things up */ + { + time_t now = CURRENT_TIME; + if (inode->i_ctime != now || inode->i_mtime != now) { + inode->i_ctime = inode->i_mtime = now; + mark_inode_dirty_sync(inode); + } + } + + + // Ok, we are done with all the checks. + + // Now we should start real work + + /* If we are going to write past the file's packed tail or if we are going + to overwrite part of the tail, we need that tail to be converted into + unformatted node */ + res = reiserfs_check_for_tail_and_convert( inode, pos, count); + if (res) + goto out; + + while ( count > 0) { + /* This is the main loop in which we running until some error occures + or until we write all of the data. */ + int num_pages;/* amount of pages we are going to write this iteration */ + int write_bytes; /* amount of bytes to write during this iteration */ + int blocks_to_allocate; /* how much blocks we need to allocate for + this iteration */ + + /* (pos & (PAGE_CACHE_SIZE-1)) is an idiom for offset into a page of pos*/ + num_pages = !!((pos+count) & (PAGE_CACHE_SIZE - 1)) + /* round up partial + pages */ + ((count + (pos & (PAGE_CACHE_SIZE-1))) >> PAGE_CACHE_SHIFT); + /* convert size to amount of + pages */ +/* all lock_kernels should be changed to lock_supers in reiserfs, but they need to be changed all at once and all together */ + lock_kernel(); + if ( num_pages > REISERFS_WRITE_PAGES_AT_A_TIME + || num_pages > reiserfs_can_fit_pages(inode->i_sb) ) { + /* If we were asked to write more data than we want to or if there + is not that much space, then we shorten amount of data to write + for this iteration. */ + num_pages = min_t(int, REISERFS_WRITE_PAGES_AT_A_TIME, reiserfs_can_fit_pages(inode->i_sb)); + /* Also we should not forget to set size in bytes accordingly */ + write_bytes = num_pages * PAGE_CACHE_SIZE - + (pos & (PAGE_CACHE_SIZE-1)); + /* If position is not on the + start of the page, we need + to substract the offset + within page */ + } else + write_bytes = count; + + /* reserve the blocks to be allocated later, so that later on + we still have the space to write the blocks to */ + reiserfs_claim_blocks_to_be_allocated(inode->i_sb, num_pages * (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize)); + unlock_kernel(); + + if ( !num_pages ) { /* If we do not have enough space even for */ + res = -ENOSPC; /* single page, return -ENOSPC */ + if ( pos > (inode->i_size & (inode->i_sb->s_blocksize-1))) + break; // In case we are writing past the file end, break. + // Otherwise we are possibly overwriting the file, so + // let's set write size to be equal or less than blocksize. + // This way we get it correctly for file holes. + // But overwriting files on absolutelly full volumes would not + // be very efficient. Well, people are not supposed to fill + // 100% of disk space anyway. + write_bytes = min_t(int, count, inode->i_sb->s_blocksize - (pos & (inode->i_sb->s_blocksize - 1))); + num_pages = 1; + } + + /* Prepare for writing into the region, read in all the + partially overwritten pages, if needed. And lock the pages, + so that nobody else can access these until we are done. + We get number of actual blocks needed as a result.*/ + blocks_to_allocate = reiserfs_prepare_file_region_for_write(inode, pos, num_pages, write_bytes, prepared_pages); + if ( blocks_to_allocate < 0 ) { + res = blocks_to_allocate; + reiserfs_release_claimed_blocks(inode->i_sb, num_pages * (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize)); + break; + } + + /* First we correct our estimate of how many blocks we need */ + reiserfs_release_claimed_blocks(inode->i_sb, num_pages * (PAGE_CACHE_SIZE>>inode->i_sb->s_blocksize_bits) - blocks_to_allocate ); + + if ( blocks_to_allocate > 0) {/*We only allocate blocks if we need to*/ + /* Fill in all the possible holes and append the file if needed */ + res = reiserfs_allocate_blocks_for_region(inode, pos, num_pages, write_bytes, prepared_pages, blocks_to_allocate); + } else if ( pos + write_bytes > inode->i_size ) { + /* File might have grown even though no new blocks were added */ + inode->i_size = pos + write_bytes; + inode->i_sb->s_op->dirty_inode(inode); + } + + /* well, we have allocated the blocks, so it is time to free + the reservation we made earlier. */ + reiserfs_release_claimed_blocks(inode->i_sb, blocks_to_allocate); + if ( res ) { + reiserfs_unprepare_pages(prepared_pages, num_pages); + break; + } + +/* NOTE that allocating blocks and filling blocks can be done in reverse order + and probably we would do that just to get rid of garbage in files after a + crash */ + + /* Copy data from user-supplied buffer to file's pages */ + res = reiserfs_copy_from_user_to_file_region(pos, num_pages, write_bytes, prepared_pages, buf); + if ( res ) { + reiserfs_unprepare_pages(prepared_pages, num_pages); + break; + } + + /* Send the pages to disk and unlock them. */ + res = reiserfs_submit_file_region_for_write(pos, num_pages, write_bytes, prepared_pages); + if ( res ) + break; + + already_written += write_bytes; + buf += write_bytes; + *ppos = pos += write_bytes; + count -= write_bytes; + } + + if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) + res = generic_osync_inode(inode, OSYNC_METADATA|OSYNC_DATA); + + up(&inode->i_sem); + return (already_written != 0)?already_written:res; + +out: + up(&inode->i_sem); // unlock the file on exit. + return res; +} struct file_operations reiserfs_file_operations = { read: generic_file_read, - write: generic_file_write, + write: reiserfs_file_write, ioctl: reiserfs_ioctl, mmap: generic_file_mmap, release: reiserfs_file_release, diff -Nru a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c --- a/fs/reiserfs/inode.c Mon Sep 9 09:28:34 2002 +++ b/fs/reiserfs/inode.c Mon Sep 9 09:28:34 2002 @@ -913,7 +913,7 @@ copy_key (INODE_PKEY (inode), &(ih->ih_key)); - inode->i_blksize = PAGE_SIZE; + inode->i_blksize = PAGE_SIZE*32; INIT_LIST_HEAD(&inode->u.reiserfs_i.i_prealloc_list) ; @@ -1605,7 +1605,7 @@ // these do not go to on-disk stat data inode->i_ino = le32_to_cpu (ih.ih_key.k_objectid); - inode->i_blksize = PAGE_SIZE; + inode->i_blksize = PAGE_SIZE*32; inode->i_dev = sb->s_dev; // store in in-core inode the key of stat data and version all diff -Nru a/fs/reiserfs/super.c b/fs/reiserfs/super.c --- a/fs/reiserfs/super.c Mon Sep 9 09:28:34 2002 +++ b/fs/reiserfs/super.c Mon Sep 9 09:28:34 2002 @@ -1261,6 +1261,7 @@ reiserfs_proc_register( s, "oidmap", reiserfs_oidmap_in_proc ); reiserfs_proc_register( s, "journal", reiserfs_journal_in_proc ); init_waitqueue_head (&(s->u.reiserfs_sb.s_wait)); + s->u.reiserfs_sb.bitmap_lock = SPIN_LOCK_UNLOCKED; printk("%s\n", reiserfs_get_version_string()) ; return s; diff -Nru a/include/linux/reiserfs_fs.h b/include/linux/reiserfs_fs.h --- a/include/linux/reiserfs_fs.h Mon Sep 9 09:28:34 2002 +++ b/include/linux/reiserfs_fs.h Mon Sep 9 09:28:34 2002 @@ -2007,6 +2007,7 @@ #endif void reiserfs_claim_blocks_to_be_allocated( struct super_block *sb, int blocks); void reiserfs_release_claimed_blocks( struct super_block *sb, int blocks); +int reiserfs_can_fit_pages(struct super_block *sb); /* hashes.c */ __u32 keyed_hash (const signed char *msg, int len); diff -Nru a/include/linux/reiserfs_fs_sb.h b/include/linux/reiserfs_fs_sb.h --- a/include/linux/reiserfs_fs_sb.h Mon Sep 9 09:28:34 2002 +++ b/include/linux/reiserfs_fs_sb.h Mon Sep 9 09:28:34 2002 @@ -466,6 +466,7 @@ reiserfs_proc_info_data_t s_proc_info_data; struct proc_dir_entry *procdir; int reserved_blocks; /* amount of blocks reserved for further allocations */ + spinlock_t bitmap_lock; /* this lock on now only used to protect reserved_blocks variable */ }; /* Definitions of reiserfs on-disk properties: */