| // Copyright 2016 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <time.h> |
| #include <unistd.h> |
| #include <sys/stat.h> |
| |
| #include <fs/block-txn.h> |
| #include <fbl/algorithm.h> |
| #include <zircon/device/vfs.h> |
| |
| #ifdef __Fuchsia__ |
| #include <zircon/syscalls.h> |
| #include <fdio/vfs.h> |
| #endif |
| |
| #include "minfs-private.h" |
| |
| namespace { |
| |
| zx_time_t minfs_gettime_utc() { |
| // linux/zircon compatible |
| struct timespec ts; |
| clock_gettime(CLOCK_REALTIME, &ts); |
| zx_time_t time = ZX_SEC(ts.tv_sec)+ts.tv_nsec; |
| return time; |
| } |
| |
| } // namespace anonymous |
| |
| namespace minfs { |
| |
| #ifdef __Fuchsia__ |
| zx_status_t VnodeMinfs::VmoReadExact(void* data, uint64_t offset, size_t len) { |
| size_t actual; |
| zx_status_t status = vmo_.read(data, offset, len, &actual); |
| if (status != ZX_OK) { |
| return status; |
| } else if (actual != len) { |
| return ZX_ERR_IO; |
| } |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::VmoWriteExact(const void* data, uint64_t offset, size_t len) { |
| size_t actual; |
| zx_status_t status = vmo_.write(data, offset, len, &actual); |
| if (status != ZX_OK) { |
| return status; |
| } else if (actual != len) { |
| return ZX_ERR_IO; |
| } |
| return ZX_OK; |
| } |
| #endif |
| |
| |
| void VnodeMinfs::InodeSync(WriteTxn* txn, uint32_t flags) { |
| // by default, c/mtimes are not updated to current time |
| if (flags != kMxFsSyncDefault) { |
| zx_time_t cur_time = minfs_gettime_utc(); |
| // update times before syncing |
| if ((flags & kMxFsSyncMtime) != 0) { |
| inode_.modify_time = cur_time; |
| } |
| if ((flags & kMxFsSyncCtime) != 0) { |
| inode_.create_time = cur_time; |
| } |
| } |
| |
| fs_->InodeSync(txn, ino_, &inode_); |
| } |
| |
| zx_status_t VnodeMinfs::BlocksShrinkDirect(WriteTxn *txn, size_t count, blk_t* barray, |
| bool* dirty) { |
| // release direct blocks |
| for (unsigned i = 0; i < count; i++) { |
| if (barray[i] == 0) { |
| continue; |
| } |
| fs_->ValidateBno(barray[i]); |
| fs_->BlockFree(txn, barray[i]); |
| barray[i] = 0; |
| inode_.block_count--; |
| *dirty = true; |
| } |
| |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::BlocksShrinkIndirect(WriteTxn* txn, uint32_t bindex, size_t count, |
| uint32_t ib_vmo_offset, blk_t* iarray, |
| bool* dirty) { |
| // release indirect blocks |
| for (unsigned i = 0; i < count; i++) { |
| if (iarray[i] == 0) { |
| continue; |
| } |
| fs_->ValidateBno(iarray[i]); |
| |
| #ifdef __Fuchsia__ |
| uint32_t* entry; |
| ReadIndirectVmoBlock(ib_vmo_offset + i, &entry); |
| #else |
| uint32_t entry[kMinfsBlockSize]; |
| ReadIndirectBlock(iarray[i], entry); |
| #endif |
| |
| // release the blocks pointed at by the entries in the indirect block |
| zx_status_t status; |
| uint32_t direct_start = i == 0 ? bindex : 0; |
| if ((status = BlocksShrinkDirect(txn, kMinfsDirectPerIndirect - direct_start, |
| &entry[direct_start], dirty)) != ZX_OK) { |
| return status; |
| } |
| |
| // only update the indirect block if an entry was deleted |
| if (*dirty) { |
| #ifdef __Fuchsia__ |
| validate_vmo_size(vmo_indirect_->GetVmo(), ib_vmo_offset + i); |
| txn->Enqueue(vmoid_indirect_, ib_vmo_offset + i, iarray[i] + fs_->info_.dat_block, 1); |
| #else |
| fs_->bc_->Writeblk(iarray[i] + fs_->info_.dat_block, entry); |
| #endif |
| } |
| |
| // Only delete the indirect block if all direct blocks have been deleted |
| if (direct_start == 0) { |
| // release the direct block itself |
| fs_->BlockFree(txn, iarray[i]); |
| iarray[i] = 0; |
| inode_.block_count--; |
| *dirty = true; |
| } |
| } |
| |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::BlocksShrinkDoublyIndirect(WriteTxn *txn, uint32_t ibindex, uint32_t bindex, |
| size_t count, uint32_t dib_vmo_offset, |
| uint32_t ib_vmo_offset, blk_t* diarray, |
| bool* dirty) { |
| // release doubly indirect blocks |
| for (unsigned i = 0; i < count; i++) { |
| if (diarray[i] == 0) { |
| continue; |
| } |
| |
| fs_->ValidateBno(diarray[i]); |
| |
| #ifdef __Fuchsia__ |
| uint32_t* dientry; |
| ReadIndirectVmoBlock(GetVmoOffsetForDoublyIndirect(i), &dientry); |
| #else |
| uint32_t dientry[kMinfsBlockSize]; |
| ReadIndirectBlock(diarray[i], dientry); |
| #endif |
| |
| // release the blocks pointed at by the entries in the indirect block |
| uint32_t indirect_start = i == 0 ? ibindex : 0; |
| uint32_t direct_start = (i == 0 && indirect_start == ibindex) ? bindex : 0; |
| zx_status_t status; |
| if ((status = BlocksShrinkIndirect(txn, direct_start, |
| kMinfsDirectPerIndirect - indirect_start, |
| ib_vmo_offset + i + indirect_start, |
| &dientry[indirect_start], dirty)) |
| != ZX_OK) { |
| return status; |
| } |
| |
| // only update the indirect block if an entry was deleted |
| if (*dirty) { |
| #ifdef __Fuchsia__ |
| validate_vmo_size(vmo_indirect_->GetVmo(), dib_vmo_offset + i); |
| txn->Enqueue(vmoid_indirect_, dib_vmo_offset + i, diarray[i] + fs_->info_.dat_block, 1); |
| #else |
| fs_->bc_->Writeblk(diarray[i] + fs_->info_.dat_block, dientry); |
| #endif |
| } |
| |
| // Only delete the doubly indirect block if all indirect blocks have been deleted |
| if (indirect_start == 0 && direct_start == 0) { |
| // release the doubly indirect block itself |
| fs_->BlockFree(txn, diarray[i]); |
| diarray[i] = 0; |
| inode_.block_count--; |
| *dirty = true; |
| } |
| } |
| |
| return ZX_OK; |
| } |
| |
| // Delete all blocks (relative to a file) from "start" (inclusive) to the end of |
| // the file. Does not update mtime/atime. |
| zx_status_t VnodeMinfs::BlocksShrink(WriteTxn *txn, blk_t start) { |
| bool dirty = false; |
| zx_status_t status = ZX_OK; |
| size_t size = (kMinfsIndirect + kMinfsDoublyIndirect) * kMinfsBlockSize; |
| |
| size_t count = start <= kMinfsDirect ? kMinfsDirect - start : 0; |
| if ((status = BlocksShrinkDirect(txn, count, &inode_.dnum[start], &dirty)) |
| != ZX_OK) { |
| return status; |
| } |
| |
| if (start < kMinfsDirect) { |
| start = 0; |
| } else { |
| start -= kMinfsDirect; |
| } |
| |
| uint32_t ibindex = start / kMinfsDirectPerIndirect; |
| uint32_t bindex = start % kMinfsDirectPerIndirect; |
| count = ibindex <= kMinfsIndirect ? kMinfsIndirect - ibindex : 0; |
| if ((status = BlocksShrinkIndirect(txn, bindex, count, ibindex, &inode_.inum[ibindex], &dirty)) |
| != ZX_OK) { |
| return status; |
| } |
| |
| if (start < kMinfsIndirect * kMinfsDirectPerIndirect) { |
| start = 0; |
| } else { |
| start -= kMinfsIndirect * kMinfsDirectPerIndirect; |
| |
| uint32_t last_dindirect = start / (kMinfsDirectPerIndirect * kMinfsDirectPerIndirect); |
| uint32_t first_indirect = start % (kMinfsDirectPerIndirect * kMinfsDirectPerIndirect); |
| |
| if (first_indirect > 0) { |
| size = GetVmoSizeForIndirect(last_dindirect); |
| } else if (last_dindirect > 0) { |
| size = GetVmoSizeForIndirect(last_dindirect - 1); |
| } |
| } |
| |
| uint32_t dibindex = start / (kMinfsDirectPerIndirect * kMinfsDirectPerIndirect); |
| start %= kMinfsDirectPerIndirect * kMinfsDirectPerIndirect; |
| ibindex = start / kMinfsDirectPerIndirect; |
| bindex = start % kMinfsDirectPerIndirect; |
| count = dibindex <= kMinfsDoublyIndirect ? kMinfsDoublyIndirect - dibindex : 0; |
| if ((status = BlocksShrinkDoublyIndirect(txn, ibindex, bindex, count, |
| GetVmoOffsetForDoublyIndirect(dibindex), |
| GetVmoOffsetForIndirect(dibindex), |
| &inode_.dinum[dibindex], &dirty)) != ZX_OK) { |
| return status; |
| } |
| |
| #ifdef __Fuchsia__ |
| if (vmo_indirect_ != nullptr && vmo_indirect_->GetSize() > size) { |
| if ((status = vmo_indirect_->Shrink(size)) != ZX_OK) { |
| return status; |
| } |
| } |
| #endif |
| |
| if (dirty) { |
| InodeSync(txn, kMxFsSyncDefault); |
| } |
| |
| return ZX_OK; |
| } |
| |
| #ifdef __Fuchsia__ |
| zx_status_t VnodeMinfs::LoadIndirectBlocks(blk_t* iarray, uint32_t count, uint32_t offset, |
| uint64_t size) { |
| zx_status_t status; |
| if ((status = InitIndirectVmo()) != ZX_OK) { |
| return status; |
| } |
| |
| if (vmo_indirect_->GetSize() < size) { |
| zx_status_t status; |
| if ((status = vmo_indirect_->Grow(size)) != ZX_OK) { |
| return status; |
| } |
| } |
| |
| ReadTxn txn(fs_->bc_.get()); |
| |
| for (uint32_t i = 0; i < count; i++) { |
| blk_t ibno; |
| if ((ibno = iarray[i]) != 0) { |
| fs_->ValidateBno(ibno); |
| txn.Enqueue(vmoid_indirect_, offset + i, ibno + fs_->info_.dat_block, 1); |
| } |
| } |
| |
| return txn.Flush(); |
| } |
| |
| zx_status_t VnodeMinfs::LoadIndirectWithinDoublyIndirect(uint32_t dindex) { |
| uint32_t* dientry; |
| |
| size_t size = GetVmoSizeForIndirect(dindex); |
| if (vmo_indirect_->GetSize() >= size) { |
| // We've already loaded this indirect (within dind) block. |
| return ZX_OK; |
| } |
| |
| ReadIndirectVmoBlock(GetVmoOffsetForDoublyIndirect(dindex), &dientry); |
| return LoadIndirectBlocks(dientry, kMinfsDirectPerIndirect, |
| GetVmoOffsetForIndirect(dindex), size); |
| } |
| |
| zx_status_t VnodeMinfs::InitIndirectVmo() { |
| if (vmo_indirect_ != nullptr) { |
| return ZX_OK; |
| } |
| |
| zx_status_t status; |
| if ((status = MappedVmo::Create(kMinfsBlockSize * (kMinfsIndirect + kMinfsDoublyIndirect), |
| "minfs-indirect", &vmo_indirect_)) != ZX_OK) { |
| return status; |
| } |
| if ((status = fs_->bc_->AttachVmo(vmo_indirect_->GetVmo(), &vmoid_indirect_)) != ZX_OK) { |
| vmo_indirect_ = nullptr; |
| return status; |
| } |
| |
| // Load initial set of indirect blocks |
| if ((status = LoadIndirectBlocks(inode_.inum, kMinfsIndirect, 0, 0)) != ZX_OK) { |
| vmo_indirect_ = nullptr; |
| return status; |
| } |
| |
| // Load doubly indirect blocks |
| if ((status = LoadIndirectBlocks(inode_.dinum, kMinfsDoublyIndirect, |
| GetVmoOffsetForDoublyIndirect(0), |
| GetVmoSizeForDoublyIndirect()) != ZX_OK)) { |
| vmo_indirect_ = nullptr; |
| return status; |
| } |
| |
| return ZX_OK; |
| } |
| |
| // Since we cannot yet register the filesystem as a paging service (and cleanly |
| // fault on pages when they are actually needed), we currently read an entire |
| // file to a VMO when a file's data block are accessed. |
| // |
| // TODO(smklein): Even this hack can be optimized; a bitmap could be used to |
| // track all 'empty/read/dirty' blocks for each vnode, rather than reading |
| // the entire file. |
| zx_status_t VnodeMinfs::InitVmo() { |
| if (vmo_.is_valid()) { |
| return ZX_OK; |
| } |
| |
| zx_status_t status; |
| if ((status = zx::vmo::create(fbl::round_up(inode_.size, kMinfsBlockSize), |
| 0, &vmo_)) != ZX_OK) { |
| FS_TRACE_ERROR("Failed to initialize vmo; error: %d\n", status); |
| return status; |
| } |
| |
| zx_object_set_property(vmo_.get(), ZX_PROP_NAME, "minfs-inode", 11); |
| |
| if ((status = fs_->bc_->AttachVmo(vmo_.get(), &vmoid_)) != ZX_OK) { |
| vmo_.reset(); |
| return status; |
| } |
| ReadTxn txn(fs_->bc_.get()); |
| |
| // Initialize all direct blocks |
| blk_t bno; |
| for (uint32_t d = 0; d < kMinfsDirect; d++) { |
| if ((bno = inode_.dnum[d]) != 0) { |
| fs_->ValidateBno(bno); |
| txn.Enqueue(vmoid_, d, bno + fs_->info_.dat_block, 1); |
| } |
| } |
| |
| // Initialize all indirect blocks |
| for (uint32_t i = 0; i < kMinfsIndirect; i++) { |
| blk_t ibno; |
| if ((ibno = inode_.inum[i]) != 0) { |
| fs_->ValidateBno(ibno); |
| |
| // Only initialize the indirect vmo if it is being used. |
| if ((status = InitIndirectVmo()) != ZX_OK) { |
| vmo_.reset(); |
| return status; |
| } |
| |
| uint32_t* ientry; |
| ReadIndirectVmoBlock(i, &ientry); |
| |
| for (uint32_t j = 0; j < kMinfsDirectPerIndirect; j++) { |
| if ((bno = ientry[j]) != 0) { |
| fs_->ValidateBno(bno); |
| uint32_t n = kMinfsDirect + i * kMinfsDirectPerIndirect + j; |
| txn.Enqueue(vmoid_, n, bno + fs_->info_.dat_block, 1); |
| } |
| } |
| } |
| } |
| |
| // Initialize all doubly indirect blocks |
| for (uint32_t i = 0; i < kMinfsDoublyIndirect; i++) { |
| blk_t dibno; |
| |
| if ((dibno = inode_.dinum[i]) != 0) { |
| fs_->ValidateBno(dibno); |
| |
| // Only initialize the doubly indirect vmo if it is being used. |
| if ((status = InitIndirectVmo()) != ZX_OK) { |
| vmo_.reset(); |
| return status; |
| } |
| |
| uint32_t* dientry; |
| ReadIndirectVmoBlock(GetVmoOffsetForDoublyIndirect(i), &dientry); |
| |
| for (uint32_t j = 0; j < kMinfsDirectPerIndirect; j++) { |
| blk_t ibno; |
| if ((ibno = dientry[j]) != 0) { |
| fs_->ValidateBno(ibno); |
| |
| // Only initialize the indirect vmo if it is being used. |
| if ((status = LoadIndirectWithinDoublyIndirect(i)) != ZX_OK) { |
| vmo_.reset(); |
| return status; |
| } |
| |
| uint32_t* ientry; |
| ReadIndirectVmoBlock(GetVmoOffsetForIndirect(i) + j, &ientry); |
| |
| for (uint32_t k = 0; k < kMinfsDirectPerIndirect; k++) { |
| if ((bno = ientry[k]) != 0) { |
| fs_->ValidateBno(bno); |
| uint32_t n = kMinfsDirect + kMinfsIndirect * kMinfsDirectPerIndirect |
| + j * kMinfsDirectPerIndirect + k; |
| txn.Enqueue(vmoid_, n, bno + fs_->info_.dat_block, 1); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| return txn.Flush(); |
| } |
| #endif |
| |
| zx_status_t VnodeMinfs::GetBnoDirect(WriteTxn* txn, blk_t* bno, bool* dirty) { |
| // direct blocks are simple... is there an entry in dnum[]? |
| blk_t hint = 0; |
| |
| if (*bno == 0) { |
| if (txn == nullptr) { |
| *bno = 0; |
| return ZX_OK; |
| } |
| // allocate a new block |
| zx_status_t status = fs_->BlockNew(txn, hint, bno); |
| if (status != ZX_OK) { |
| return status; |
| } |
| inode_.block_count++; |
| *dirty = true; |
| } |
| |
| fs_->ValidateBno(*bno); |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::GetBnoIndirect(WriteTxn* txn, uint32_t bindex, uint32_t ib_vmo_offset, |
| blk_t* ibno, blk_t* bno, bool* dirty) { |
| // we should have initialized vmo before calling this method |
| zx_status_t status; |
| |
| #ifdef __Fuchsia__ |
| if ((status = VnodeMinfs::InitIndirectVmo()) != ZX_OK) { |
| return status; |
| } |
| #endif |
| |
| // retrieve indirect block at this index |
| if (*ibno == 0) { |
| if (txn == nullptr) { |
| *bno = 0; |
| return ZX_OK; |
| } |
| // allocate new indirect block if it does not exist |
| if ((status = fs_->BlockNew(txn, 0, ibno)) != ZX_OK) { |
| return status; |
| } |
| |
| #ifdef __Fuchsia__ |
| ClearIndirectVmoBlock(ib_vmo_offset); |
| #else |
| ClearIndirectBlock(*ibno); |
| #endif |
| |
| inode_.block_count++; |
| *dirty = true; |
| } |
| |
| #ifdef __Fuchsia__ |
| uint32_t* ientry; |
| ReadIndirectVmoBlock(ib_vmo_offset, &ientry); |
| #else |
| uint32_t ientry[kMinfsBlockSize]; |
| ReadIndirectBlock(*ibno, ientry); |
| #endif |
| |
| bool direct_dirty = false; |
| if ((status = GetBnoDirect(txn, &ientry[bindex], &direct_dirty)) != ZX_OK) { |
| return status; |
| } |
| |
| *bno = ientry[bindex]; |
| |
| if (*dirty || direct_dirty) { |
| // Write back the indirect block if a new block was allocated |
| #ifdef __Fuchsia__ |
| txn->Enqueue(vmoid_indirect_, ib_vmo_offset, *ibno + fs_->info_.dat_block, 1); |
| #else |
| fs_->bc_->Writeblk(*ibno + fs_->info_.dat_block, ientry); |
| #endif |
| InodeSync(txn, kMxFsSyncDefault); |
| } |
| |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::GetBnoDoublyIndirect(WriteTxn* txn, uint32_t ibindex, uint32_t bindex, |
| uint32_t dib_vmo_offset, uint32_t ib_vmo_offset, |
| blk_t* dibno, blk_t* bno, bool* dirty) { |
| zx_status_t status; |
| |
| // look up the doubly indirect bno, create if it doesn't already exist |
| if (*dibno == 0) { |
| if (txn == nullptr) { |
| *bno = 0; |
| return ZX_OK; |
| } |
| |
| // allocate a new doubly indirect block |
| if ((status = fs_->BlockNew(txn, 0, dibno)) != ZX_OK) { |
| return status; |
| } |
| |
| #ifdef __Fuchsia__ |
| ClearIndirectVmoBlock(dib_vmo_offset); |
| #else |
| ClearIndirectBlock(*dibno); |
| #endif |
| |
| // record new doubly indirect block in inode, note that we need to update |
| inode_.block_count++; |
| *dirty = true; |
| } |
| |
| // read from doubly indirect block |
| #ifdef __Fuchsia__ |
| uint32_t* dientry; |
| ReadIndirectVmoBlock(dib_vmo_offset, &dientry); |
| #else |
| uint32_t dientry[kMinfsBlockSize]; |
| ReadIndirectBlock(*dibno, dientry); |
| #endif |
| |
| // get indirect block |
| bool indirect_dirty = false; |
| if ((status = GetBnoIndirect(txn, bindex, ib_vmo_offset + ibindex, &dientry[ibindex], bno, |
| &indirect_dirty)) != ZX_OK) { |
| return status; |
| } |
| |
| if (*dirty || indirect_dirty) { |
| // Write back the doubly indirect block if a new block was allocated |
| #ifdef __Fuchsia__ |
| txn->Enqueue(vmoid_indirect_, dib_vmo_offset, *dibno + fs_->info_.dat_block, 1); |
| #else |
| fs_->bc_->Writeblk(*dibno + fs_->info_.dat_block, dientry); |
| #endif |
| InodeSync(txn, kMxFsSyncDefault); |
| } |
| |
| return ZX_OK; |
| } |
| |
| #ifdef __Fuchsia__ |
| void VnodeMinfs::ReadIndirectVmoBlock(uint32_t offset, uint32_t** entry) { |
| ZX_DEBUG_ASSERT(vmo_indirect_ != nullptr); |
| uintptr_t addr = reinterpret_cast<uintptr_t>(vmo_indirect_->GetData()); |
| validate_vmo_size(vmo_indirect_->GetVmo(), offset); |
| *entry = reinterpret_cast<uint32_t*>(addr + kMinfsBlockSize * offset); |
| } |
| |
| void VnodeMinfs::ClearIndirectVmoBlock(uint32_t offset) { |
| ZX_DEBUG_ASSERT(vmo_indirect_ != nullptr); |
| uintptr_t addr = reinterpret_cast<uintptr_t>(vmo_indirect_->GetData()); |
| validate_vmo_size(vmo_indirect_->GetVmo(), offset); |
| memset(reinterpret_cast<void*>(addr + kMinfsBlockSize * offset), 0, kMinfsBlockSize); |
| } |
| #else |
| void VnodeMinfs::ReadIndirectBlock(blk_t bno, uint32_t* entry) { |
| fs_->bc_->Readblk(bno + fs_->info_.dat_block, entry); |
| } |
| |
| void VnodeMinfs::ClearIndirectBlock(blk_t bno) { |
| uint32_t data[kMinfsBlockSize]; |
| memset(data, 0, kMinfsBlockSize); |
| fs_->bc_->Writeblk(bno + fs_->info_.dat_block, data); |
| } |
| #endif |
| |
| // Get the bno corresponding to the nth logical block within the file. |
| zx_status_t VnodeMinfs::GetBno(WriteTxn* txn, blk_t n, blk_t* bno) { |
| bool dirty = false; |
| |
| if (n < kMinfsDirect) { |
| zx_status_t status = GetBnoDirect(txn, &inode_.dnum[n], &dirty); |
| *bno = inode_.dnum[n]; |
| return status; |
| } |
| |
| // for indirect blocks, adjust past the direct blocks |
| n -= kMinfsDirect; |
| |
| if (n < kMinfsIndirect * kMinfsDirectPerIndirect) { |
| // index of indirect block |
| uint32_t ibindex = n / kMinfsDirectPerIndirect; |
| // index of direct block within indirect block |
| uint32_t bindex = n % kMinfsDirectPerIndirect; |
| return GetBnoIndirect(txn, bindex, ibindex, &inode_.inum[ibindex], bno, &dirty); |
| } |
| |
| // for doubly indirect blocks, adjust past the indirect blocks |
| n -= (kMinfsIndirect * kMinfsDirectPerIndirect); |
| |
| if (n < kMinfsDoublyIndirect * kMinfsDirectPerIndirect * kMinfsDirectPerIndirect) { |
| // index of doubly indirect block |
| uint32_t dibindex = n / (kMinfsDirectPerIndirect * kMinfsDirectPerIndirect); |
| ZX_DEBUG_ASSERT(dibindex < kMinfsDoublyIndirect); |
| n -= (dibindex * kMinfsDirectPerIndirect * kMinfsDirectPerIndirect); |
| // index of indirect block within doubly indirect block |
| uint32_t ibindex = n / kMinfsDirectPerIndirect; |
| // index of direct block within indirect block |
| uint32_t bindex = n % kMinfsDirectPerIndirect; |
| |
| #ifdef __Fuchsia__ |
| zx_status_t status; |
| // If the vmo_indirect_ vmo has not been created, make it now. |
| if ((status = InitIndirectVmo()) != ZX_OK) { |
| return status; |
| } |
| |
| // Grow VMO if we need more space to fit this set of indirect blocks |
| uint64_t vmo_size = GetVmoSizeForIndirect(dibindex); |
| if (vmo_indirect_->GetSize() < vmo_size) { |
| if ((status = vmo_indirect_->Grow(vmo_size)) != ZX_OK) { |
| return status; |
| } |
| } |
| #endif |
| |
| return GetBnoDoublyIndirect(txn, ibindex, bindex, GetVmoOffsetForDoublyIndirect(dibindex), |
| GetVmoOffsetForIndirect(dibindex), &inode_.dinum[dibindex], bno, |
| &dirty); |
| } |
| |
| return ZX_ERR_OUT_OF_RANGE; |
| } |
| |
| // Immediately stop iterating over the directory. |
| #define DIR_CB_DONE 0 |
| // Access the next direntry in the directory. Offsets updated. |
| #define DIR_CB_NEXT 1 |
| // Identify that the direntry record was modified. Stop iterating. |
| #define DIR_CB_SAVE_SYNC 2 |
| |
| zx_status_t VnodeMinfs::ReadExactInternal(void* data, size_t len, size_t off) { |
| size_t actual; |
| zx_status_t status = ReadInternal(data, len, off, &actual); |
| if (status != ZX_OK) { |
| return status; |
| } else if (actual != len) { |
| return ZX_ERR_IO; |
| } |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::WriteExactInternal(WriteTxn* txn, const void* data, |
| size_t len, size_t off) { |
| size_t actual; |
| zx_status_t status = WriteInternal(txn, data, len, off, &actual); |
| if (status != ZX_OK) { |
| return status; |
| } else if (actual != len) { |
| return ZX_ERR_IO; |
| } |
| InodeSync(txn, kMxFsSyncMtime); |
| return ZX_OK; |
| } |
| |
| static zx_status_t validate_dirent(minfs_dirent_t* de, size_t bytes_read, size_t off) { |
| uint32_t reclen = static_cast<uint32_t>(MinfsReclen(de, off)); |
| if ((bytes_read < MINFS_DIRENT_SIZE) || (reclen < MINFS_DIRENT_SIZE)) { |
| FS_TRACE_ERROR("vn_dir: Could not read dirent at offset: %zd\n", off); |
| return ZX_ERR_IO; |
| } else if ((off + reclen > kMinfsMaxDirectorySize) || (reclen & 3)) { |
| FS_TRACE_ERROR("vn_dir: bad reclen %u > %u\n", reclen, kMinfsMaxDirectorySize); |
| return ZX_ERR_IO; |
| } else if (de->ino != 0) { |
| if ((de->namelen == 0) || |
| (de->namelen > (reclen - MINFS_DIRENT_SIZE))) { |
| FS_TRACE_ERROR("vn_dir: bad namelen %u / %u\n", de->namelen, reclen); |
| return ZX_ERR_IO; |
| } |
| } |
| return ZX_OK; |
| } |
| |
| // Updates offset information to move to the next direntry in the directory. |
| static zx_status_t do_next_dirent(minfs_dirent_t* de, DirectoryOffset* offs) { |
| offs->off_prev = offs->off; |
| offs->off += MinfsReclen(de, offs->off); |
| return DIR_CB_NEXT; |
| } |
| |
| static zx_status_t cb_dir_find(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| if ((de->ino != 0) && fbl::StringPiece(de->name, de->namelen) == args->name) { |
| args->ino = de->ino; |
| args->type = de->type; |
| return DIR_CB_DONE; |
| } else { |
| return do_next_dirent(de, offs); |
| } |
| } |
| |
| zx_status_t VnodeMinfs::CanUnlink() const { |
| // directories must be empty (dirent_count == 2) |
| if (IsDirectory()) { |
| if (inode_.dirent_count != 2) { |
| // if we have more than "." and "..", not empty, cannot unlink |
| return ZX_ERR_NOT_EMPTY; |
| #ifdef __Fuchsia__ |
| } else if (IsRemote()) { |
| // we cannot unlink mount points |
| return ZX_ERR_UNAVAILABLE; |
| #endif |
| } |
| } |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::UnlinkChild(WriteTxn* txn, |
| fbl::RefPtr<VnodeMinfs> childvn, |
| minfs_dirent_t* de, DirectoryOffset* offs) { |
| // Coalesce the current dirent with the previous/next dirent, if they |
| // (1) exist and (2) are free. |
| size_t off_prev = offs->off_prev; |
| size_t off = offs->off; |
| size_t off_next = off + MinfsReclen(de, off); |
| minfs_dirent_t de_prev, de_next; |
| zx_status_t status; |
| |
| // Read the direntries we're considering merging with. |
| // Verify they are free and small enough to merge. |
| size_t coalesced_size = MinfsReclen(de, off); |
| // Coalesce with "next" first, so the kMinfsReclenLast bit can easily flow |
| // back to "de" and "de_prev". |
| if (!(de->reclen & kMinfsReclenLast)) { |
| size_t len = MINFS_DIRENT_SIZE; |
| if ((status = ReadExactInternal(&de_next, len, off_next)) != ZX_OK) { |
| FS_TRACE_ERROR("unlink: Failed to read next dirent\n"); |
| return status; |
| } else if ((status = validate_dirent(&de_next, len, off_next)) != ZX_OK) { |
| FS_TRACE_ERROR("unlink: Read invalid dirent\n"); |
| return status; |
| } |
| if (de_next.ino == 0) { |
| coalesced_size += MinfsReclen(&de_next, off_next); |
| // If the next entry *was* last, then 'de' is now last. |
| de->reclen |= (de_next.reclen & kMinfsReclenLast); |
| } |
| } |
| if (off_prev != off) { |
| size_t len = MINFS_DIRENT_SIZE; |
| if ((status = ReadExactInternal(&de_prev, len, off_prev)) != ZX_OK) { |
| FS_TRACE_ERROR("unlink: Failed to read previous dirent\n"); |
| return status; |
| } else if ((status = validate_dirent(&de_prev, len, off_prev)) != ZX_OK) { |
| FS_TRACE_ERROR("unlink: Read invalid dirent\n"); |
| return status; |
| } |
| if (de_prev.ino == 0) { |
| coalesced_size += MinfsReclen(&de_prev, off_prev); |
| off = off_prev; |
| } |
| } |
| |
| if (!(de->reclen & kMinfsReclenLast) && (coalesced_size >= kMinfsReclenMask)) { |
| // Should only be possible if the on-disk record format is corrupted |
| return ZX_ERR_IO; |
| } |
| de->ino = 0; |
| de->reclen = static_cast<uint32_t>(coalesced_size & kMinfsReclenMask) | |
| (de->reclen & kMinfsReclenLast); |
| // Erase dirent (replace with 'empty' dirent) |
| if ((status = WriteExactInternal(txn, de, MINFS_DIRENT_SIZE, off)) != ZX_OK) { |
| return status; |
| } |
| |
| if (de->reclen & kMinfsReclenLast) { |
| // Truncating the directory merely removed unused space; if it fails, |
| // the directory contents are still valid. |
| TruncateInternal(txn, off + MINFS_DIRENT_SIZE); |
| } |
| |
| inode_.dirent_count--; |
| |
| if (MinfsMagicType(childvn->inode_.magic) == kMinfsTypeDir) { |
| // Child directory had '..' which pointed to parent directory |
| inode_.link_count--; |
| } |
| childvn->RemoveInodeLink(txn); |
| return DIR_CB_SAVE_SYNC; |
| } |
| |
| void VnodeMinfs::RemoveInodeLink(WriteTxn* txn) { |
| // This effectively 'unlinks' the target node without deleting the direntry |
| inode_.link_count--; |
| if (MinfsMagicType(inode_.magic) == kMinfsTypeDir) { |
| if (inode_.link_count == 1) { |
| // Directories are initialized with two links, since they point |
| // to themselves via ".". Thus, when they reach "one link", they |
| // are only pointed to by themselves, and should be deleted. |
| inode_.link_count--; |
| flags_ |= kMinfsFlagDeletedDirectory; |
| } |
| } |
| |
| InodeSync(txn, kMxFsSyncMtime); |
| } |
| |
| // caller is expected to prevent unlink of "." or ".." |
| static zx_status_t cb_dir_unlink(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| if ((de->ino == 0) || fbl::StringPiece(de->name, de->namelen) != args->name) { |
| return do_next_dirent(de, offs); |
| } |
| |
| fbl::RefPtr<VnodeMinfs> vn; |
| zx_status_t status; |
| if ((status = vndir->fs_->VnodeGet(&vn, de->ino)) < 0) { |
| return status; |
| } |
| |
| // If a directory was requested, then only try unlinking a directory |
| if ((args->type == kMinfsTypeDir) && !vn->IsDirectory()) { |
| return ZX_ERR_NOT_DIR; |
| } |
| if ((status = vn->CanUnlink()) != ZX_OK) { |
| return status; |
| } |
| return vndir->UnlinkChild(args->txn, fbl::move(vn), de, offs); |
| } |
| |
| // same as unlink, but do not validate vnode |
| static zx_status_t cb_dir_force_unlink(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| if ((de->ino == 0) || fbl::StringPiece(de->name, de->namelen) != args->name) { |
| return do_next_dirent(de, offs); |
| } |
| |
| fbl::RefPtr<VnodeMinfs> vn; |
| zx_status_t status; |
| if ((status = vndir->fs_->VnodeGet(&vn, de->ino)) < 0) { |
| return status; |
| } |
| return vndir->UnlinkChild(args->txn, fbl::move(vn), de, offs); |
| } |
| |
| // Given a (name, inode, type) combination: |
| // - If no corresponding 'name' is found, ZX_ERR_NOT_FOUND is returned |
| // - If the 'name' corresponds to a vnode, check that the target vnode: |
| // - Does not have the same inode as the argument inode |
| // - Is the same type as the argument 'type' |
| // - Is unlinkable |
| // - If the previous checks pass, then: |
| // - Remove the old vnode (decrement link count by one) |
| // - Replace the old vnode's position in the directory with the new inode |
| static zx_status_t cb_dir_attempt_rename(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| if ((de->ino == 0) || fbl::StringPiece(de->name, de->namelen) != args->name) { |
| return do_next_dirent(de, offs); |
| } |
| |
| fbl::RefPtr<VnodeMinfs> vn; |
| zx_status_t status; |
| if ((status = vndir->fs_->VnodeGet(&vn, de->ino)) < 0) { |
| return status; |
| } else if (args->ino == vn->ino_) { |
| // cannot rename node to itself |
| return ZX_ERR_BAD_STATE; |
| } else if (args->type != de->type) { |
| // cannot rename directory to file (or vice versa) |
| return ZX_ERR_BAD_STATE; |
| } else if ((status = vn->CanUnlink()) != ZX_OK) { |
| // if we cannot unlink the target, we cannot rename the target |
| return status; |
| } |
| |
| // If we are renaming ON TOP of a directory, then we can skip |
| // updating the parent link count -- the old directory had a ".." entry to |
| // the parent (link count of 1), but the new directory will ALSO have a ".." |
| // entry, making the rename operation idempotent w.r.t. the parent link |
| // count. |
| vn->RemoveInodeLink(args->txn); |
| |
| de->ino = args->ino; |
| status = vndir->WriteExactInternal(args->txn, de, DirentSize(de->namelen), offs->off); |
| if (status != ZX_OK) { |
| return status; |
| } |
| return DIR_CB_SAVE_SYNC; |
| } |
| |
| static zx_status_t cb_dir_update_inode(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| if ((de->ino == 0) || fbl::StringPiece(de->name, de->namelen) != args->name) { |
| return do_next_dirent(de, offs); |
| } |
| |
| de->ino = args->ino; |
| zx_status_t status = vndir->WriteExactInternal(args->txn, de, |
| DirentSize(de->namelen), |
| offs->off); |
| if (status != ZX_OK) { |
| return status; |
| } |
| return DIR_CB_SAVE_SYNC; |
| } |
| |
| static zx_status_t add_dirent(fbl::RefPtr<VnodeMinfs> vndir, |
| minfs_dirent_t* de, DirArgs* args, size_t off) { |
| de->ino = args->ino; |
| de->type = static_cast<uint8_t>(args->type); |
| de->namelen = static_cast<uint8_t>(args->name.length()); |
| memcpy(de->name, args->name.data(), de->namelen); |
| zx_status_t status = vndir->WriteExactInternal(args->txn, de, |
| DirentSize(de->namelen), |
| off); |
| if (status != ZX_OK) { |
| return status; |
| } |
| vndir->inode_.dirent_count++; |
| if (args->type == kMinfsTypeDir) { |
| // Child directory has '..' which will point to parent directory |
| vndir->inode_.link_count++; |
| } |
| return DIR_CB_SAVE_SYNC; |
| } |
| |
| static zx_status_t cb_dir_append(fbl::RefPtr<VnodeMinfs> vndir, minfs_dirent_t* de, |
| DirArgs* args, DirectoryOffset* offs) { |
| uint32_t reclen = static_cast<uint32_t>(MinfsReclen(de, offs->off)); |
| if (de->ino == 0) { |
| // empty entry, do we fit? |
| if (args->reclen > reclen) { |
| return do_next_dirent(de, offs); |
| } |
| return add_dirent(fbl::move(vndir), de, args, offs->off); |
| } else { |
| // filled entry, can we sub-divide? |
| uint32_t size = static_cast<uint32_t>(DirentSize(de->namelen)); |
| if (size > reclen) { |
| FS_TRACE_ERROR("bad reclen (smaller than dirent) %u < %u\n", reclen, size); |
| return ZX_ERR_IO; |
| } |
| uint32_t extra = reclen - size; |
| if (extra < args->reclen) { |
| return do_next_dirent(de, offs); |
| } |
| // shrink existing entry |
| bool was_last_record = de->reclen & kMinfsReclenLast; |
| de->reclen = size; |
| zx_status_t status = vndir->WriteExactInternal(args->txn, de, |
| DirentSize(de->namelen), |
| offs->off); |
| if (status != ZX_OK) { |
| return status; |
| } |
| offs->off += size; |
| // create new entry in the remaining space |
| char data[kMinfsMaxDirentSize]; |
| de = (minfs_dirent_t*) data; |
| de->reclen = extra | (was_last_record ? kMinfsReclenLast : 0); |
| return add_dirent(fbl::move(vndir), de, args, offs->off); |
| } |
| } |
| |
| // Calls a callback 'func' on all direntries in a directory 'vn' with the |
| // provided arguments, reacting to the return code of the callback. |
| // |
| // When 'func' is called, it receives a few arguments: |
| // 'vndir': The directory on which the callback is operating |
| // 'de': A pointer the start of a single dirent. |
| // Only DirentSize(de->namelen) bytes are guaranteed to exist in |
| // memory from this starting pointer. |
| // 'args': Additional arguments plumbed through ForEachDirent |
| // 'offs': Offset info about where in the directory this direntry is located. |
| // Since 'func' may create / remove surrounding dirents, it is responsible for |
| // updating the offset information to access the next dirent. |
| zx_status_t VnodeMinfs::ForEachDirent(DirArgs* args, const DirentCallback func) { |
| char data[kMinfsMaxDirentSize]; |
| minfs_dirent_t* de = (minfs_dirent_t*) data; |
| DirectoryOffset offs = { |
| .off = 0, |
| .off_prev = 0, |
| }; |
| while (offs.off + MINFS_DIRENT_SIZE < kMinfsMaxDirectorySize) { |
| FS_TRACE(MINFS, "Reading dirent at offset %zd\n", offs.off); |
| size_t r; |
| zx_status_t status = ReadInternal(data, kMinfsMaxDirentSize, offs.off, &r); |
| if (status != ZX_OK) { |
| return status; |
| } else if ((status = validate_dirent(de, r, offs.off)) != ZX_OK) { |
| return status; |
| } |
| |
| switch ((status = func(fbl::RefPtr<VnodeMinfs>(this), de, args, &offs))) { |
| case DIR_CB_NEXT: |
| break; |
| case DIR_CB_SAVE_SYNC: |
| inode_.seq_num++; |
| InodeSync(args->txn, kMxFsSyncMtime); |
| return ZX_OK; |
| case DIR_CB_DONE: |
| default: |
| return status; |
| } |
| } |
| return ZX_ERR_NOT_FOUND; |
| } |
| |
| VnodeMinfs::~VnodeMinfs() { |
| if (inode_.link_count == 0) { |
| fs_->InoFree(this); |
| } |
| |
| fs_->VnodeRelease(this); |
| #ifdef __Fuchsia__ |
| // Detach the vmoids from the underlying block device, |
| // so the underlying VMO may be released. |
| size_t request_count = 0; |
| block_fifo_request_t request[2]; |
| if (vmo_.is_valid()) { |
| request[request_count].txnid = fs_->bc_->TxnId(); |
| request[request_count].vmoid = vmoid_; |
| request[request_count].opcode = BLOCKIO_CLOSE_VMO; |
| request_count++; |
| } |
| if (vmo_indirect_ != nullptr) { |
| request[request_count].txnid = fs_->bc_->TxnId(); |
| request[request_count].vmoid = vmoid_indirect_; |
| request[request_count].opcode = BLOCKIO_CLOSE_VMO; |
| request_count++; |
| } |
| if (request_count) { |
| fs_->bc_->Txn(&request[0], request_count); |
| } |
| #endif |
| } |
| |
| zx_status_t VnodeMinfs::ValidateFlags(uint32_t flags) { |
| FS_TRACE(MINFS, "VnodeMinfs::ValidateFlags(0x%x) vn=%p(#%u)\n", flags, this, ino_); |
| if ((flags & O_DIRECTORY) && !IsDirectory()) { |
| return ZX_ERR_NOT_DIR; |
| } |
| |
| switch (flags & O_ACCMODE) { |
| case O_WRONLY: |
| case O_RDWR: |
| if (IsDirectory()) { |
| return ZX_ERR_NOT_FILE; |
| } |
| } |
| |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Read(void* data, size_t len, size_t off, size_t* out_actual) { |
| FS_TRACE(MINFS, "minfs_read() vn=%p(#%u) len=%zd off=%zd\n", this, ino_, len, off); |
| if (IsDirectory()) { |
| return ZX_ERR_NOT_FILE; |
| } |
| zx_status_t status = ReadInternal(data, len, off, out_actual); |
| if (status != ZX_OK) { |
| return status; |
| } |
| return ZX_OK; |
| } |
| |
| // Internal read. Usable on directories. |
| zx_status_t VnodeMinfs::ReadInternal(void* data, size_t len, size_t off, size_t* actual) { |
| // clip to EOF |
| if (off >= inode_.size) { |
| *actual = 0; |
| return ZX_OK; |
| } |
| if (len > (inode_.size - off)) { |
| len = inode_.size - off; |
| } |
| |
| zx_status_t status; |
| #ifdef __Fuchsia__ |
| if ((status = InitVmo()) != ZX_OK) { |
| return status; |
| } else if ((status = vmo_.read(data, off, len, actual)) != ZX_OK) { |
| return status; |
| } |
| #else |
| void* start = data; |
| uint32_t n = off / kMinfsBlockSize; |
| size_t adjust = off % kMinfsBlockSize; |
| |
| while ((len > 0) && (n < kMinfsMaxFileBlock)) { |
| size_t xfer; |
| if (len > (kMinfsBlockSize - adjust)) { |
| xfer = kMinfsBlockSize - adjust; |
| } else { |
| xfer = len; |
| } |
| |
| blk_t bno; |
| if ((status = GetBno(nullptr, n, &bno)) != ZX_OK) { |
| return status; |
| } |
| if (bno != 0) { |
| char bdata[kMinfsBlockSize]; |
| if (fs_->ReadDat(bno, bdata)) { |
| return ZX_ERR_IO; |
| } |
| memcpy(data, bdata + adjust, xfer); |
| } else { |
| // If the block is not allocated, just read zeros |
| memset(data, 0, xfer); |
| } |
| |
| adjust = 0; |
| len -= xfer; |
| data = (void*)((uintptr_t)data + xfer); |
| n++; |
| } |
| *actual = (uintptr_t)data - (uintptr_t)start; |
| #endif |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Write(const void* data, size_t len, size_t offset, size_t* out_actual) { |
| FS_TRACE(MINFS, "minfs_write() vn=%p(#%u) len=%zd off=%zd\n", this, ino_, len, offset); |
| if (IsDirectory()) { |
| return ZX_ERR_NOT_FILE; |
| } |
| WriteTxn txn(fs_->bc_.get()); |
| zx_status_t status = WriteInternal(&txn, data, len, offset, out_actual); |
| if (status != ZX_OK) { |
| return status; |
| } |
| if (*out_actual != 0) { |
| InodeSync(&txn, kMxFsSyncMtime); // Successful writes updates mtime |
| } |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Append(const void* data, size_t len, size_t* out_end, |
| size_t* out_actual) { |
| zx_status_t status = Write(data, len, inode_.size, out_actual); |
| *out_end = inode_.size; |
| return status; |
| } |
| |
| // Internal write. Usable on directories. |
| zx_status_t VnodeMinfs::WriteInternal(WriteTxn* txn, const void* data, |
| size_t len, size_t off, size_t* actual) { |
| if (len == 0) { |
| *actual = 0; |
| return ZX_OK; |
| } |
| |
| zx_status_t status; |
| #ifdef __Fuchsia__ |
| if ((status = InitVmo()) != ZX_OK) { |
| return status; |
| } |
| #else |
| size_t max_size = off + len; |
| #endif |
| const void* const start = data; |
| uint32_t n = static_cast<uint32_t>(off / kMinfsBlockSize); |
| size_t adjust = off % kMinfsBlockSize; |
| |
| while ((len > 0) && (n < kMinfsMaxFileBlock)) { |
| size_t xfer; |
| if (len > (kMinfsBlockSize - adjust)) { |
| xfer = kMinfsBlockSize - adjust; |
| } else { |
| xfer = len; |
| } |
| |
| #ifdef __Fuchsia__ |
| size_t xfer_off = n * kMinfsBlockSize + adjust; |
| if ((xfer_off + xfer) > inode_.size) { |
| size_t new_size = xfer_off + xfer; |
| if ((status = vmo_.set_size(fbl::round_up(new_size, kMinfsBlockSize))) != ZX_OK) { |
| goto done; |
| } |
| } |
| |
| // Update this block of the in-memory VMO |
| if ((status = VmoWriteExact(data, xfer_off, xfer)) != ZX_OK) { |
| goto done; |
| } |
| |
| // Update this block on-disk |
| blk_t bno; |
| if ((status = GetBno(txn, n, &bno)) != ZX_OK) { |
| goto done; |
| } |
| ZX_DEBUG_ASSERT(bno != 0); |
| txn->Enqueue(vmoid_, n, bno + fs_->info_.dat_block, 1); |
| #else |
| blk_t bno; |
| if ((status = GetBno(txn, n, &bno)) != ZX_OK) { |
| goto done; |
| } |
| ZX_DEBUG_ASSERT(bno != 0); |
| char wdata[kMinfsBlockSize]; |
| if (fs_->bc_->Readblk(bno + fs_->info_.dat_block, wdata)) { |
| goto done; |
| } |
| memcpy(wdata + adjust, data, xfer); |
| if (len < kMinfsBlockSize && max_size >= inode_.size) { |
| memset(wdata + adjust + xfer, 0, kMinfsBlockSize - (adjust + xfer)); |
| } |
| if (fs_->bc_->Writeblk(bno + fs_->info_.dat_block, wdata)) { |
| goto done; |
| } |
| #endif |
| |
| adjust = 0; |
| len -= xfer; |
| data = (void*)((uintptr_t)(data) + xfer); |
| n++; |
| } |
| |
| done: |
| len = (uintptr_t)data - (uintptr_t)start; |
| if (len == 0) { |
| // If more than zero bytes were requested, but zero bytes were written, |
| // return an error explicitly (rather than zero). |
| if (off >= kMinfsMaxFileSize) { |
| return ZX_ERR_FILE_BIG; |
| } |
| |
| return ZX_ERR_NO_SPACE; |
| } |
| if ((off + len) > inode_.size) { |
| inode_.size = static_cast<uint32_t>(off + len); |
| } |
| |
| *actual = len; |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Lookup(fbl::RefPtr<fs::Vnode>* out, fbl::StringPiece name) { |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(name)); |
| |
| if (!IsDirectory()) { |
| FS_TRACE_ERROR("not directory\n"); |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| |
| return LookupInternal(out, name); |
| } |
| |
| zx_status_t VnodeMinfs::LookupInternal(fbl::RefPtr<fs::Vnode>* out, fbl::StringPiece name) { |
| DirArgs args = DirArgs(); |
| args.name = name; |
| zx_status_t status; |
| if ((status = ForEachDirent(&args, cb_dir_find)) < 0) { |
| return status; |
| } |
| fbl::RefPtr<VnodeMinfs> vn; |
| if ((status = fs_->VnodeGet(&vn, args.ino)) < 0) { |
| return status; |
| } |
| *out = fbl::move(vn); |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Getattr(vnattr_t* a) { |
| FS_TRACE(MINFS, "minfs_getattr() vn=%p(#%u)\n", this, ino_); |
| a->mode = DTYPE_TO_VTYPE(MinfsMagicType(inode_.magic)) | |
| V_IRUSR | V_IWUSR | V_IRGRP | V_IROTH; |
| a->inode = ino_; |
| a->size = inode_.size; |
| a->blksize = kMinfsBlockSize; |
| a->blkcount = inode_.block_count * (kMinfsBlockSize / VNATTR_BLKSIZE); |
| a->nlink = inode_.link_count; |
| a->create_time = inode_.create_time; |
| a->modify_time = inode_.modify_time; |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Setattr(const vnattr_t* a) { |
| int dirty = 0; |
| FS_TRACE(MINFS, "minfs_setattr() vn=%p(#%u)\n", this, ino_); |
| if ((a->valid & ~(ATTR_CTIME|ATTR_MTIME)) != 0) { |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| if ((a->valid & ATTR_CTIME) != 0) { |
| inode_.create_time = a->create_time; |
| dirty = 1; |
| } |
| if ((a->valid & ATTR_MTIME) != 0) { |
| inode_.modify_time = a->modify_time; |
| dirty = 1; |
| } |
| if (dirty) { |
| // write to disk, but don't overwrite the time |
| WriteTxn txn(fs_->bc_.get()); |
| InodeSync(&txn, kMxFsSyncDefault); |
| } |
| return ZX_OK; |
| } |
| |
| typedef struct dircookie { |
| size_t off; // Offset into directory |
| uint32_t reserved; // Unused |
| uint32_t seqno; // inode seq no |
| } dircookie_t; |
| |
| static_assert(sizeof(dircookie_t) <= sizeof(fs::vdircookie_t), |
| "MinFS dircookie too large to fit in IO state"); |
| |
| zx_status_t VnodeMinfs::Readdir(fs::vdircookie_t* cookie, void* dirents, size_t len, |
| size_t* out_actual) { |
| FS_TRACE(MINFS, "minfs_readdir() vn=%p(#%u) cookie=%p len=%zd\n", this, ino_, cookie, len); |
| dircookie_t* dc = reinterpret_cast<dircookie_t*>(cookie); |
| fs::DirentFiller df(dirents, len); |
| |
| if (!IsDirectory()) { |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| |
| size_t off = dc->off; |
| size_t r; |
| char data[kMinfsMaxDirentSize]; |
| minfs_dirent_t* de = (minfs_dirent_t*) data; |
| |
| if (off != 0 && dc->seqno != inode_.seq_num) { |
| // The offset *might* be invalid, if we called Readdir after a directory |
| // has been modified. In this case, we need to re-read the directory |
| // until we get to the direntry at or after the previously identified offset. |
| |
| size_t off_recovered = 0; |
| while (off_recovered < off) { |
| if (off_recovered + MINFS_DIRENT_SIZE >= kMinfsMaxDirectorySize) { |
| goto fail; |
| } |
| zx_status_t status = ReadInternal(de, kMinfsMaxDirentSize, off_recovered, &r); |
| if ((status != ZX_OK) || (validate_dirent(de, r, off_recovered) != ZX_OK)) { |
| goto fail; |
| } |
| off_recovered += MinfsReclen(de, off_recovered); |
| } |
| off = off_recovered; |
| } |
| |
| while (off + MINFS_DIRENT_SIZE < kMinfsMaxDirectorySize) { |
| zx_status_t status = ReadInternal(de, kMinfsMaxDirentSize, off, &r); |
| if (status != ZX_OK) { |
| goto fail; |
| } else if (validate_dirent(de, r, off) != ZX_OK) { |
| goto fail; |
| } |
| |
| fbl::StringPiece name(de->name, de->namelen); |
| |
| if (de->ino && name != "..") { |
| zx_status_t status; |
| if ((status = df.Next(name, de->type)) != ZX_OK) { |
| // no more space |
| goto done; |
| } |
| } |
| |
| off += MinfsReclen(de, off); |
| } |
| |
| done: |
| // save our place in the dircookie |
| dc->off = off; |
| dc->seqno = inode_.seq_num; |
| *out_actual = df.BytesFilled(); |
| ZX_DEBUG_ASSERT(*out_actual <= len); // Otherwise, we're overflowing the input buffer. |
| return ZX_OK; |
| |
| fail: |
| dc->off = 0; |
| return ZX_ERR_IO; |
| } |
| |
| #ifdef __Fuchsia__ |
| VnodeMinfs::VnodeMinfs(Minfs* fs) : |
| fs_(fs), vmo_(ZX_HANDLE_INVALID), vmo_indirect_(nullptr) {} |
| |
| void VnodeMinfs::Notify(fbl::StringPiece name, unsigned event) { watcher_.Notify(name, event); } |
| zx_status_t VnodeMinfs::WatchDir(fs::Vfs* vfs, const vfs_watch_dir_t* cmd) { |
| return watcher_.WatchDir(vfs, this, cmd); |
| } |
| |
| bool VnodeMinfs::IsRemote() const { return remoter_.IsRemote(); } |
| zx::channel VnodeMinfs::DetachRemote() { return remoter_.DetachRemote(); } |
| zx_handle_t VnodeMinfs::GetRemote() const { return remoter_.GetRemote(); } |
| void VnodeMinfs::SetRemote(zx::channel remote) { return remoter_.SetRemote(fbl::move(remote)); } |
| |
| #else |
| VnodeMinfs::VnodeMinfs(Minfs* fs) : fs_(fs) {} |
| #endif |
| |
| zx_status_t VnodeMinfs::Allocate(Minfs* fs, uint32_t type, fbl::RefPtr<VnodeMinfs>* out) { |
| zx_status_t status = AllocateHollow(fs, out); |
| if (status != ZX_OK) { |
| return status; |
| } |
| memset(&(*out)->inode_, 0, sizeof((*out)->inode_)); |
| (*out)->inode_.magic = MinfsMagic(type); |
| (*out)->inode_.create_time = (*out)->inode_.modify_time = minfs_gettime_utc(); |
| (*out)->inode_.link_count = (type == kMinfsTypeDir ? 2 : 1); |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::AllocateHollow(Minfs* fs, fbl::RefPtr<VnodeMinfs>* out) { |
| fbl::AllocChecker ac; |
| *out = fbl::AdoptRef(new (&ac) VnodeMinfs(fs)); |
| if (!ac.check()) { |
| return ZX_ERR_NO_MEMORY; |
| } |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Create(fbl::RefPtr<fs::Vnode>* out, fbl::StringPiece name, uint32_t mode) { |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(name)); |
| |
| if (!IsDirectory()) { |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| if (IsDeletedDirectory()) { |
| return ZX_ERR_BAD_STATE; |
| } |
| |
| DirArgs args = DirArgs(); |
| args.name = name; |
| // ensure file does not exist |
| zx_status_t status; |
| if ((status = ForEachDirent(&args, cb_dir_find)) != ZX_ERR_NOT_FOUND) { |
| return ZX_ERR_ALREADY_EXISTS; |
| } |
| |
| // creating a directory? |
| uint32_t type = S_ISDIR(mode) ? kMinfsTypeDir : kMinfsTypeFile; |
| |
| WriteTxn txn(fs_->bc_.get()); |
| // mint a new inode and vnode for it |
| fbl::RefPtr<VnodeMinfs> vn; |
| if ((status = fs_->VnodeNew(&txn, &vn, type)) < 0) { |
| return status; |
| } |
| |
| // If the new node is a directory, fill it with '.' and '..'. |
| if (type == kMinfsTypeDir) { |
| char bdata[DirentSize(1) + DirentSize(2)]; |
| minfs_dir_init(bdata, vn->ino_, ino_); |
| size_t expected = DirentSize(1) + DirentSize(2); |
| if (vn->WriteExactInternal(&txn, bdata, expected, 0) != ZX_OK) { |
| return ZX_ERR_IO; |
| } |
| vn->inode_.dirent_count = 2; |
| vn->InodeSync(&txn, kMxFsSyncDefault); |
| } |
| |
| // add directory entry for the new child node |
| args.ino = vn->ino_; |
| args.type = type; |
| args.reclen = static_cast<uint32_t>(DirentSize(static_cast<uint8_t>(name.length()))); |
| args.txn = &txn; |
| if ((status = ForEachDirent(&args, cb_dir_append)) < 0) { |
| return status; |
| } |
| |
| *out = fbl::move(vn); |
| return ZX_OK; |
| } |
| |
| constexpr const char kFsName[] = "minfs"; |
| |
| zx_status_t VnodeMinfs::Ioctl(uint32_t op, const void* in_buf, size_t in_len, void* out_buf, |
| size_t out_len, size_t* out_actual) { |
| switch (op) { |
| case IOCTL_VFS_QUERY_FS: { |
| if (out_len < (sizeof(vfs_query_info_t) + strlen(kFsName))) { |
| return ZX_ERR_INVALID_ARGS; |
| } |
| |
| vfs_query_info_t* info = static_cast<vfs_query_info_t*>(out_buf); |
| info->total_bytes = fs_->info_.block_count * fs_->info_.block_size; |
| info->used_bytes = fs_->info_.alloc_block_count * fs_->info_.block_size; |
| info->total_nodes = fs_->info_.inode_count; |
| info->used_nodes = fs_->info_.alloc_inode_count; |
| memcpy(info->name, kFsName, strlen(kFsName)); |
| *out_actual = sizeof(vfs_query_info_t) + strlen(kFsName); |
| return ZX_OK; |
| } |
| case IOCTL_VFS_UNMOUNT_FS: { |
| zx_status_t status = Sync(); |
| if (status != ZX_OK) { |
| FS_TRACE_ERROR("minfs unmount failed to sync; unmounting anyway: %d\n", status); |
| } |
| // 'fs_' is deleted after Unmount is called. |
| *out_actual = 0; |
| return fs_->Unmount(); |
| } |
| #ifdef __Fuchsia__ |
| case IOCTL_VFS_GET_DEVICE_PATH: { |
| ssize_t len = fs_->bc_->GetDevicePath(static_cast<char*>(out_buf), out_len); |
| |
| if ((ssize_t)out_len < len) { |
| return ZX_ERR_INVALID_ARGS; |
| } |
| if (len >= 0) { |
| *out_actual = len; |
| } |
| return len > 0 ? ZX_OK : static_cast<zx_status_t>(len); |
| } |
| #endif |
| default: { |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| } |
| } |
| |
| zx_status_t VnodeMinfs::Unlink(fbl::StringPiece name, bool must_be_dir) { |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(name)); |
| |
| if (!IsDirectory()) { |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| WriteTxn txn(fs_->bc_.get()); |
| DirArgs args = DirArgs(); |
| args.name = name; |
| args.type = must_be_dir ? kMinfsTypeDir : 0; |
| args.txn = &txn; |
| return ForEachDirent(&args, cb_dir_unlink); |
| } |
| |
| zx_status_t VnodeMinfs::Truncate(size_t len) { |
| if (IsDirectory()) { |
| return ZX_ERR_NOT_FILE; |
| } |
| |
| WriteTxn txn(fs_->bc_.get()); |
| zx_status_t status = TruncateInternal(&txn, len); |
| if (status == ZX_OK) { |
| // Successful truncates update inode |
| InodeSync(&txn, kMxFsSyncMtime); |
| } |
| return status; |
| } |
| |
| zx_status_t VnodeMinfs::TruncateInternal(WriteTxn* txn, size_t len) { |
| zx_status_t r = 0; |
| #ifdef __Fuchsia__ |
| // TODO(smklein): We should only init up to 'len'; no need |
| // to read in the portion of a large file we plan on deleting. |
| if (InitVmo() != ZX_OK) { |
| return ZX_ERR_IO; |
| } |
| #endif |
| |
| if (len < inode_.size) { |
| // Truncate should make the file shorter |
| blk_t bno = inode_.size / kMinfsBlockSize; |
| blk_t trunc_bno = static_cast<blk_t>(len / kMinfsBlockSize); |
| |
| // Truncate to the nearest block |
| if (trunc_bno <= bno) { |
| blk_t start_bno = static_cast<blk_t>((len % kMinfsBlockSize == 0) ? |
| trunc_bno : trunc_bno + 1); |
| if ((r = BlocksShrink(txn, start_bno)) < 0) { |
| return r; |
| } |
| |
| if (start_bno * kMinfsBlockSize < inode_.size) { |
| inode_.size = start_bno * kMinfsBlockSize; |
| } |
| } |
| |
| // Write zeroes to the rest of the remaining block, if it exists |
| if (len < inode_.size) { |
| char bdata[kMinfsBlockSize]; |
| blk_t rel_bno = static_cast<blk_t>(len / kMinfsBlockSize); |
| if (GetBno(nullptr, rel_bno, &bno) != ZX_OK) { |
| return ZX_ERR_IO; |
| } |
| if (bno != 0) { |
| size_t adjust = len % kMinfsBlockSize; |
| #ifdef __Fuchsia__ |
| if ((r = VmoReadExact(bdata, len - adjust, adjust)) != ZX_OK) { |
| return ZX_ERR_IO; |
| } |
| memset(bdata + adjust, 0, kMinfsBlockSize - adjust); |
| |
| if ((r = VmoWriteExact(bdata, len - adjust, kMinfsBlockSize)) != ZX_OK) { |
| return ZX_ERR_IO; |
| } |
| txn->Enqueue(vmoid_, rel_bno, bno + fs_->info_.dat_block, 1); |
| #else |
| if (fs_->bc_->Readblk(bno + fs_->info_.dat_block, bdata)) { |
| return ZX_ERR_IO; |
| } |
| memset(bdata + adjust, 0, kMinfsBlockSize - adjust); |
| if (fs_->bc_->Writeblk(bno + fs_->info_.dat_block, bdata)) { |
| return ZX_ERR_IO; |
| } |
| #endif |
| } |
| } |
| } else if (len > inode_.size) { |
| // Truncate should make the file longer, filled with zeroes. |
| if (kMinfsMaxFileSize < len) { |
| return ZX_ERR_INVALID_ARGS; |
| } |
| } |
| |
| inode_.size = static_cast<uint32_t>(len); |
| #ifdef __Fuchsia__ |
| if ((r = vmo_.set_size(fbl::round_up(len, kMinfsBlockSize))) != ZX_OK) { |
| return r; |
| } |
| #endif |
| |
| return ZX_OK; |
| } |
| |
| // verify that the 'newdir' inode is not a subdirectory of the source. |
| static zx_status_t check_not_subdirectory(fbl::RefPtr<VnodeMinfs> src, fbl::RefPtr<VnodeMinfs> newdir) { |
| fbl::RefPtr<VnodeMinfs> vn = newdir; |
| zx_status_t status = ZX_OK; |
| while (vn->ino_ != kMinfsRootIno) { |
| if (vn->ino_ == src->ino_) { |
| status = ZX_ERR_INVALID_ARGS; |
| break; |
| } |
| |
| fbl::RefPtr<fs::Vnode> out = nullptr; |
| if ((status = vn->LookupInternal(&out, "..")) < 0) { |
| break; |
| } |
| vn = fbl::RefPtr<VnodeMinfs>::Downcast(out); |
| } |
| return status; |
| } |
| |
| zx_status_t VnodeMinfs::Rename(fbl::RefPtr<fs::Vnode> _newdir, fbl::StringPiece oldname, |
| fbl::StringPiece newname, bool src_must_be_dir, |
| bool dst_must_be_dir) { |
| auto newdir = fbl::RefPtr<VnodeMinfs>::Downcast(_newdir); |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(oldname)); |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(newname)); |
| |
| // ensure that the vnodes containing oldname and newname are directories |
| if (!(IsDirectory() && newdir->IsDirectory())) |
| return ZX_ERR_NOT_SUPPORTED; |
| |
| zx_status_t status; |
| fbl::RefPtr<VnodeMinfs> oldvn = nullptr; |
| // acquire the 'oldname' node (it must exist) |
| DirArgs args = DirArgs(); |
| args.name = oldname; |
| if ((status = ForEachDirent(&args, cb_dir_find)) < 0) { |
| return status; |
| } else if ((status = fs_->VnodeGet(&oldvn, args.ino)) < 0) { |
| return status; |
| } else if ((status = check_not_subdirectory(oldvn, newdir)) < 0) { |
| return status; |
| } |
| |
| // If either the 'src' or 'dst' must be directories, BOTH of them must be directories. |
| if (!oldvn->IsDirectory() && (src_must_be_dir || dst_must_be_dir)) { |
| return ZX_ERR_NOT_DIR; |
| } |
| |
| // if the entry for 'newname' exists, make sure it can be replaced by |
| // the vnode behind 'oldname'. |
| WriteTxn txn(fs_->bc_.get()); |
| args.txn = &txn; |
| args.name = newname; |
| args.ino = oldvn->ino_; |
| args.type = oldvn->IsDirectory() ? kMinfsTypeDir : kMinfsTypeFile; |
| status = newdir->ForEachDirent(&args, cb_dir_attempt_rename); |
| if (status == ZX_ERR_NOT_FOUND) { |
| // if 'newname' does not exist, create it |
| args.reclen = static_cast<uint32_t>(DirentSize(static_cast<uint8_t>(newname.length()))); |
| if ((status = newdir->ForEachDirent(&args, cb_dir_append)) < 0) { |
| return status; |
| } |
| } else if (status != ZX_OK) { |
| return status; |
| } |
| |
| // update the oldvn's entry for '..' if (1) it was a directory, and (2) it |
| // moved to a new directory |
| if ((args.type == kMinfsTypeDir) && (ino_ != newdir->ino_)) { |
| fbl::RefPtr<fs::Vnode> vn_fs; |
| if ((status = newdir->Lookup(&vn_fs, newname)) < 0) { |
| return status; |
| } |
| auto vn = fbl::RefPtr<VnodeMinfs>::Downcast(vn_fs); |
| args.name = ".."; |
| args.ino = newdir->ino_; |
| if ((status = vn->ForEachDirent(&args, cb_dir_update_inode)) < 0) { |
| return status; |
| } |
| } |
| |
| // at this point, the oldvn exists with multiple names (or the same name in |
| // different directories) |
| oldvn->inode_.link_count++; |
| |
| // finally, remove oldname from its original position |
| args.name = oldname; |
| return ForEachDirent(&args, cb_dir_force_unlink); |
| } |
| |
| zx_status_t VnodeMinfs::Link(fbl::StringPiece name, fbl::RefPtr<fs::Vnode> _target) { |
| ZX_DEBUG_ASSERT(fs::vfs_valid_name(name)); |
| |
| if (!IsDirectory()) { |
| return ZX_ERR_NOT_SUPPORTED; |
| } else if (IsDeletedDirectory()) { |
| return ZX_ERR_BAD_STATE; |
| } |
| |
| auto target = fbl::RefPtr<VnodeMinfs>::Downcast(_target); |
| if (target->IsDirectory()) { |
| // The target must not be a directory |
| return ZX_ERR_NOT_FILE; |
| } |
| |
| // The destination should not exist |
| DirArgs args = DirArgs(); |
| args.name = name; |
| zx_status_t status; |
| if ((status = ForEachDirent(&args, cb_dir_find)) != ZX_ERR_NOT_FOUND) { |
| return (status == ZX_OK) ? ZX_ERR_ALREADY_EXISTS : status; |
| } |
| |
| WriteTxn txn(fs_->bc_.get()); |
| args.ino = target->ino_; |
| args.type = kMinfsTypeFile; // We can't hard link directories |
| args.reclen = static_cast<uint32_t>(DirentSize(static_cast<uint8_t>(name.length()))); |
| args.txn = &txn; |
| if ((status = ForEachDirent(&args, cb_dir_append)) < 0) { |
| return status; |
| } |
| |
| // We have successfully added the vn to a new location. Increment the link count. |
| target->inode_.link_count++; |
| target->InodeSync(&txn, kMxFsSyncDefault); |
| |
| return ZX_OK; |
| } |
| |
| zx_status_t VnodeMinfs::Sync() { |
| return fs_->bc_->Sync(); |
| } |
| |
| #ifdef __Fuchsia__ |
| zx_status_t VnodeMinfs::AttachRemote(fs::MountChannel h) { |
| if (!IsDirectory() || IsDeletedDirectory()) { |
| return ZX_ERR_NOT_DIR; |
| } else if (IsRemote()) { |
| return ZX_ERR_ALREADY_BOUND; |
| } |
| SetRemote(fbl::move(h.TakeChannel())); |
| return ZX_OK; |
| } |
| #endif |
| |
| } // namespace minfs |
