;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; Copyright (C) KolibriOS team 2011. All rights reserved. ;; ;; Distributed under terms of the GNU General Public License ;; ;; ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; $Revision$ ; This function is intended to replace the old 'hd_read' function when ; [hdd_appl_data] = 0, so its input/output parameters are the same, except ; that it can't use the global variables 'hd_error' and 'hdd_appl_data'. ; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure ; eax is relative to partition start ; out: eax = error code; 0 = ok fs_read32_sys: ; Compatibility hack: if PARTITION.Disk is 'old', there is no DISK structure, ; this request should be processed by hd_read. cmp [ebp+PARTITION.Disk], 'old' jnz @f mov [hdd_appl_data], 0 call hd_read mov [hdd_appl_data], 1 ; restore to default state ret @@: ; In the normal case, save ecx, set ecx to SysCache and let the common part ; do its work. push ecx mov ecx, [ebp+PARTITION.Disk] add ecx, DISK.SysCache jmp fs_read32_common ; This function is intended to replace the old 'hd_read' function when ; [hdd_appl_data] = 1, so its input/output parameters are the same, except ; that it can't use the global variables 'hd_error' and 'hdd_appl_data'. ; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure ; eax is relative to partition start ; out: eax = error code; 0 = ok fs_read32_app: ; Compatibility hack: if PARTITION.Disk is 'old', there is no DISK structure, ; this request should be processed by hd_read. cmp [ebp+PARTITION.Disk], 'old' jnz @f mov [hdd_appl_data], 1 jmp hd_read @@: ; In the normal case, save ecx, set ecx to AppCache and let the common part ; do its work. push ecx mov ecx, [ebp+PARTITION.Disk] add ecx, DISK.AppCache ; This label is the common part of fs_read32_sys and fs_read32_app. fs_read32_common: ; 1. Check that the required sector is inside the partition. If no, return ; DISK_STATUS_END_OF_MEDIA. cmp dword [ebp+PARTITION.Length+4], 0 jnz @f cmp dword [ebp+PARTITION.Length], eax ja @f mov eax, DISK_STATUS_END_OF_MEDIA pop ecx ret @@: ; 2. Get the absolute sector on the disk. push edx xor edx, edx add eax, dword [ebp+PARTITION.FirstSector] adc edx, dword [ebp+PARTITION.FirstSector+4] ; 3. If there is no cache for this disk, just pass the request to the driver. cmp [ecx+DISKCACHE.pointer], 0 jnz .scancache push 1 push esp ; numsectors push edx ; startsector push eax ; startsector push ebx ; buffer mov al, DISKFUNC.read call disk_call_driver pop ecx pop edx pop ecx ret .scancache: ; 4. Scan the cache. push esi edi ecx ; scan cache push edx eax virtual at esp .sector_lo dd ? .sector_hi dd ? .cache dd ? end virtual ; The following code is inherited from hd_read. The differences are: ; all code is protected by the cache lock; instead of static calls ; to hd_read_dma/hd_read_pio/bd_read the dynamic call to DISKFUNC.read is used; ; sector is 64-bit, not 32-bit. call mutex_lock mov eax, [.sector_lo] mov edx, [.sector_hi] mov esi, [ecx+DISKCACHE.pointer] mov ecx, [ecx+DISKCACHE.sad_size] add esi, 12 mov edi, 1 .hdreadcache: cmp dword [esi+8], 0 ; empty je .nohdcache cmp [esi], eax ; correct sector jne .nohdcache cmp [esi+4], edx ; correct sector je .yeshdcache .nohdcache: add esi, 12 inc edi dec ecx jnz .hdreadcache mov esi, [.cache] call find_empty_slot64 ; ret in edi test eax, eax jnz .read_done push 1 push esp push edx push [.sector_lo+12] mov ecx, [.cache] mov eax, edi shl eax, 9 add eax, [ecx+DISKCACHE.data] push eax mov esi, [ebp+PARTITION.Disk] mov al, DISKFUNC.read call disk_call_driver pop ecx dec ecx jnz .read_done mov ecx, [.cache] lea eax, [edi*3] mov esi, [ecx+DISKCACHE.pointer] lea esi, [eax*4+esi] mov eax, [.sector_lo] mov edx, [.sector_hi] mov [esi], eax ; sector number mov [esi+4], edx ; sector number mov dword [esi+8], 1; hd read - mark as same as in hd .yeshdcache: mov esi, edi mov ecx, [.cache] shl esi, 9 add esi, [ecx+DISKCACHE.data] mov edi, ebx mov ecx, 512/4 rep movsd ; move data xor eax, eax ; successful read .read_done: mov ecx, [.cache] push eax call mutex_unlock pop eax add esp, 12 pop edi esi edx ecx ret ; This function is intended to replace the old 'hd_write' function when ; [hdd_appl_data] = 0, so its input/output parameters are the same, except ; that it can't use the global variables 'hd_error' and 'hdd_appl_data'. ; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure ; eax is relative to partition start ; out: eax = error code; 0 = ok fs_write32_sys: ; Compatibility hack: if PARTITION.Disk is 'old', there is no DISK structure, ; this request should be processed by hd_write. cmp [ebp+PARTITION.Disk], 'old' jnz @f mov [hdd_appl_data], 0 call hd_write mov [hdd_appl_data], 1 ; restore to default state ret @@: ; In the normal case, save ecx, set ecx to SysCache and let the common part ; do its work. push ecx mov ecx, [ebp+PARTITION.Disk] add ecx, DISK.SysCache jmp fs_write32_common ; This function is intended to replace the old 'hd_write' function when ; [hdd_appl_data] = 1, so its input/output parameters are the same, except ; that it can't use the global variables 'hd_error' and 'hdd_appl_data'. ; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure ; eax is relative to partition start ; out: eax = error code; 0 = ok fs_write32_app: ; Compatibility hack: if PARTITION.Disk is 'old', there is no DISK structure, ; this request should be processed by hd_write. cmp [ebp+PARTITION.Disk], 'old' jnz @f mov [hdd_appl_data], 1 jmp hd_write @@: ; In the normal case, save ecx, set ecx to AppCache and let the common part ; do its work. push ecx mov ecx, [ebp+PARTITION.Disk] add ecx, DISK.AppCache ; This label is the common part of fs_read32_sys and fs_read32_app. fs_write32_common: ; 1. Check that the required sector is inside the partition. If no, return ; DISK_STATUS_END_OF_MEDIA. cmp dword [ebp+PARTITION.Length+4], 0 jnz @f cmp dword [ebp+PARTITION.Length], eax ja @f mov eax, DISK_STATUS_END_OF_MEDIA pop ecx ret @@: push edx ; 2. Get the absolute sector on the disk. xor edx, edx add eax, dword [ebp+PARTITION.FirstSector] adc edx, dword [ebp+PARTITION.FirstSector+4] ; 3. If there is no cache for this disk, just pass request to the driver. cmp [ecx+DISKCACHE.pointer], 0 jnz .scancache push 1 push esp ; numsectors push edx ; startsector push eax ; startsector push ebx ; buffer mov al, DISKFUNC.write call disk_call_driver pop ecx pop edx pop ecx ret .scancache: ; 4. Scan the cache. push esi edi ecx ; scan cache push edx eax virtual at esp .sector_lo dd ? .sector_hi dd ? .cache dd ? end virtual ; The following code is inherited from hd_write. The differences are: ; all code is protected by the cache lock; ; sector is 64-bit, not 32-bit. call mutex_lock ; check if the cache already has the sector and overwrite it mov eax, [.sector_lo] mov edx, [.sector_hi] mov esi, [ecx+DISKCACHE.pointer] mov ecx, [ecx+DISKCACHE.sad_size] add esi, 12 mov edi, 1 .hdwritecache: cmp dword [esi+8], 0 ; if cache slot is empty je .not_in_cache_write cmp [esi], eax ; if the slot has the sector jne .not_in_cache_write cmp [esi+4], edx ; if the slot has the sector je .yes_in_cache_write .not_in_cache_write: add esi, 12 inc edi dec ecx jnz .hdwritecache ; sector not found in cache ; write the block to a new location mov esi, [.cache] call find_empty_slot64 ; ret in edi test eax, eax jne .hd_write_access_denied mov ecx, [.cache] lea eax, [edi*3] mov esi, [ecx+DISKCACHE.pointer] lea esi, [eax*4+esi] mov eax, [.sector_lo] mov edx, [.sector_hi] mov [esi], eax ; sector number mov [esi+4], edx ; sector number .yes_in_cache_write: mov dword [esi+4], 2 ; write - differs from hd shl edi, 9 mov ecx, [.cache] add edi, [ecx+DISKCACHE.data] mov esi, ebx mov ecx, 512/4 rep movsd ; move data xor eax, eax ; success .hd_write_access_denied: mov ecx, [.cache] push eax call mutex_unlock pop eax add esp, 12 pop edi esi edx ecx ret ; This internal function is called from fs_read32_* and fs_write32_*. It is the ; analogue of find_empty_slot for 64-bit sectors. find_empty_slot64: ;----------------------------------------------------------- ; find empty or read slot, flush cache if next 12.5% is used by write ; output : edi = cache slot ;----------------------------------------------------------- .search_again: mov ecx, [esi+DISKCACHE.sad_size] mov edi, [esi+DISKCACHE.search_start] shr ecx, 3 .search_for_empty: inc edi cmp edi, [esi+DISKCACHE.sad_size] jbe .inside_cache mov edi, 1 .inside_cache: lea eax, [edi*3] shl eax, 2 add eax, [esi+DISKCACHE.pointer] cmp dword [eax+8], 2 jb .found_slot ; it's empty or read dec ecx jnz .search_for_empty call write_cache64 ; no empty slots found, write all test eax, eax jne .found_slot_access_denied jmp .search_again ; and start again .found_slot: mov [esi+DISKCACHE.search_start], edi xor eax, eax ; success .found_slot_access_denied: ret ; This function is intended to replace the old 'write_cache' function. proc write_cache64 uses ecx edx esi edi locals cache_chain_started dd ? cache_chain_size dd ? cache_chain_pos dd ? cache_chain_ptr dd ? endl ; If there is no cache for this disk, nothing to do. cmp [esi+DISKCACHE.pointer], 0 jz .flush ;----------------------------------------------------------- ; write all changed sectors to disk ;----------------------------------------------------------- ; write difference ( 2 ) from cache to DISK mov ecx, [esi+DISKCACHE.sad_size] mov esi, [esi+DISKCACHE.pointer] add esi, 12 mov edi, 1 .write_cache_more: cmp dword [esi+8], 2 ; if cache slot is not different jne .write_chain mov dword [esi+8], 1 ; same as in hd mov eax, [esi] mov edx, [esi+4] ; edx:eax = sector to write ; Объединяем запись цепочки последовательных секторов в одно обращение к диску cmp ecx, 1 jz .nonext cmp dword [esi+12+8], 2 jnz .nonext push eax edx add eax, 1 adc edx, 0 cmp eax, [esi+12] jnz @f cmp edx, [esi+12+4] @@: pop edx eax jnz .nonext cmp [cache_chain_started], 1 jz @f mov [cache_chain_started], 1 mov [cache_chain_size], 0 mov [cache_chain_pos], edi mov [cache_chain_ptr], esi @@: inc [cache_chain_size] cmp [cache_chain_size], 16 jnz .continue jmp .write_chain .nonext: call .flush_cache_chain test eax, eax jnz .nothing mov [cache_chain_size], 1 mov [cache_chain_ptr], esi call .write_cache_sector test eax, eax jnz .nothing jmp .continue .write_chain: call .flush_cache_chain test eax, eax jnz .nothing .continue: add esi, 12 inc edi dec ecx jnz .write_cache_more call .flush_cache_chain test eax, eax jnz .nothing .flush: mov esi, [ebp] mov esi, [esi+PARTITION.Disk] mov al, DISKFUNC.flush call disk_call_driver .nothing: ret .flush_cache_chain: xor eax, eax cmp [cache_chain_started], eax jz @f call .write_cache_chain mov [cache_chain_started], 0 @@: retn .write_cache_sector: mov [cache_chain_size], 1 mov [cache_chain_pos], edi .write_cache_chain: pusha mov edi, [cache_chain_pos] mov ecx, [ebp-12] shl edi, 9 add edi, [ecx+DISKCACHE.data] mov ecx, [cache_chain_size] push ecx push esp ; numsectors mov eax, [cache_chain_ptr] pushd [eax+4] pushd [eax] ; startsector push edi ; buffer mov esi, [ebp] mov esi, [esi+PARTITION.Disk] mov al, DISKFUNC.write call disk_call_driver pop ecx mov [esp+28], eax popa retn endp ; This internal function is called from disk_add to initialize the caching for ; a new DISK. ; The algorithm is inherited from getcache.inc: take 1/32 part of the available ; physical memory, round down to 8 pages, limit by 128K from below and by 1M ; from above. Reserve 1/8 part of the cache for system data and 7/8 for app ; data. ; After the size is calculated, but before the cache is allocated, the device ; driver can adjust the size. In particular, setting size to zero disables ; caching: there is no sense in a cache for a ramdisk. In fact, such action ; is most useful example of a non-trivial adjustment. ; esi = pointer to DISK structure disk_init_cache: ; 1. Calculate the suggested cache size. ; 1a. Get the size of free physical memory in pages. mov eax, [pg_data.pages_free] ; 1b. Use the value to calculate the size. shl eax, 12 - 5 ; 1/32 of it in bytes and eax, -8*4096 ; round down to the multiple of 8 pages ; 1c. Force lower and upper limits. cmp eax, 1024*1024 jb @f mov eax, 1024*1024 @@: cmp eax, 128*1024 ja @f mov eax, 128*1024 @@: ; 1d. Give a chance to the driver to adjust the size. push eax mov al, DISKFUNC.adjust_cache_size call disk_call_driver ; Cache size calculated. mov [esi+DISK.cache_size], eax test eax, eax jz .nocache ; 2. Allocate memory for the cache. ; 2a. Call the allocator. stdcall kernel_alloc, eax test eax, eax jnz @f ; 2b. If it failed, say a message and return with eax = 0. dbgstr 'no memory for disk cache' jmp .nothing @@: ; 3. Fill two DISKCACHE structures. mov [esi+DISK.SysCache.pointer], eax lea ecx, [esi+DISK.SysCache.Lock] call mutex_init lea ecx, [esi+DISK.AppCache.Lock] call mutex_init ; The following code is inherited from getcache.inc. mov edx, [esi+DISK.SysCache.pointer] and [esi+DISK.SysCache.search_start], 0 and [esi+DISK.AppCache.search_start], 0 mov eax, [esi+DISK.cache_size] shr eax, 3 mov [esi+DISK.SysCache.data_size], eax add edx, eax imul eax, 7 mov [esi+DISK.AppCache.data_size], eax mov [esi+DISK.AppCache.pointer], edx mov eax, [esi+DISK.SysCache.data_size] push ebx call calculate_for_hd pop ebx add eax, [esi+DISK.SysCache.pointer] mov [esi+DISK.SysCache.data], eax mov [esi+DISK.SysCache.sad_size], ecx push edi mov edi, [esi+DISK.SysCache.pointer] lea ecx, [ecx*3] xor eax, eax rep stosd pop edi mov eax, [esi+DISK.AppCache.data_size] push ebx call calculate_for_hd pop ebx add eax, [esi+DISK.AppCache.pointer] mov [esi+DISK.AppCache.data], eax mov [esi+DISK.AppCache.sad_size], ecx push edi mov edi, [esi+DISK.AppCache.pointer] lea ecx, [ecx*3] xor eax, eax rep stosd pop edi ; 4. Return with nonzero al. mov al, 1 ; 5. Return. .nothing: ret ; No caching is required for this driver. Zero cache pointers and return with ; nonzero al. .nocache: mov [esi+DISK.SysCache.pointer], eax mov [esi+DISK.AppCache.pointer], eax mov al, 1 ret ; This internal function is called from disk_media_dereference to free the ; allocated cache, if there is one. ; esi = pointer to DISK structure disk_free_cache: ; The algorithm is straightforward. mov eax, [esi+DISK.SysCache.pointer] test eax, eax jz .nothing stdcall kernel_free, eax .nothing: ret