diff options
Diffstat (limited to 'include/mercury')
-rw-r--r-- | include/mercury/kernel/bd/memory.hpp | 23 | ||||
-rw-r--r-- | include/mercury/kernel/fs/tarfs.hpp | 40 | ||||
-rw-r--r-- | include/mercury/kernel/paging.hpp | 3 | ||||
-rw-r--r-- | include/mercury/kernel/storage.hpp | 130 | ||||
-rw-r--r-- | include/mercury/kernel/terminal.hpp | 3 | ||||
-rw-r--r-- | include/mercury/kernel/utility.hpp | 261 |
6 files changed, 394 insertions, 66 deletions
diff --git a/include/mercury/kernel/bd/memory.hpp b/include/mercury/kernel/bd/memory.hpp new file mode 100644 index 0000000..079abee --- /dev/null +++ b/include/mercury/kernel/bd/memory.hpp @@ -0,0 +1,23 @@ +#ifndef MERCURY_KERNEL_BD_MEMORY_HPP +#define MERCURY_KERNEL_BD_MEMORY_HPP + +#include <mercury/kernel/storage.hpp> + +namespace mercury::kernel::bd { + + class memory : public storage::block_device { + + private: + uint8_t *buffer; + + public: + memory(void *buffer, size_t buffer_len); + + storage::io_result read_blocks_no_cache(uint64_t start, uint64_t count, void *into) override; + storage::io_result write_blocks_no_cache(uint64_t start, uint64_t count, const void *from) override; + + }; + +} + +#endif diff --git a/include/mercury/kernel/fs/tarfs.hpp b/include/mercury/kernel/fs/tarfs.hpp new file mode 100644 index 0000000..41773ee --- /dev/null +++ b/include/mercury/kernel/fs/tarfs.hpp @@ -0,0 +1,40 @@ +#ifndef MERCURY_KERNEL_FS_TARFS_HPP +#define MERCURY_KERNEL_FS_TARFS_HPP + +#include <mercury/kernel/storage.hpp> + +namespace mercury::kernel::fs { + + class tarfs_instance : public storage::file_system_instance { + + private: + storage::block_device *bd; + + storage::io_result next_node(storage::node_id_t &node); + //name_buf must be at least 255 chars long. + storage::io_result read_name(storage::node_id_t node, char *name_buf, size_t &name_len_out); + //len <= 12 + storage::io_result read_num(uint64_t offset, size_t len, uint64_t &out); + + public: + tarfs_instance(storage::block_device *bd); + + storage::io_result get_root_node(storage::node_id_t &out) override; + storage::io_result get_first_child( + storage::node_id_t node, storage::node_id_t &out, storage::directory_iter_t &iter_out) override; + storage::io_result get_next_child( + storage::node_id_t node, storage::node_id_t &out, storage::directory_iter_t &iter) override; + storage::io_result get_child( + storage::node_id_t node, storage::node_id_t &out, const char *name, size_t name_len) override; + storage::io_result get_name_length(storage::node_id_t node, size_t &length_out) override; + storage::io_result get_name(storage::node_id_t node, char *buffer, size_t &length_out) override; + storage::io_result get_file_length(storage::node_id_t node, uint64_t &length_out) override; + storage::io_result get_file_type(storage::node_id_t node, storage::file_type &out) override; + + }; + + storage::io_result tarfs_mounter(storage::block_device *bd, storage::file_system_instance *&fs_out); + +} + +#endif diff --git a/include/mercury/kernel/paging.hpp b/include/mercury/kernel/paging.hpp index 9627162..4ba5fdf 100644 --- a/include/mercury/kernel/paging.hpp +++ b/include/mercury/kernel/paging.hpp @@ -26,6 +26,9 @@ namespace mercury::kernel::paging { void map_kernel_page( uint64_t paddr, uint64_t vaddr, bool write, bool execute); + //maps writable and not executable + void *map_new_kernel_pages(uint64_t count); + uint64_t get_used_vram_page_count(); uint64_t get_free_pram_page_count(); diff --git a/include/mercury/kernel/storage.hpp b/include/mercury/kernel/storage.hpp new file mode 100644 index 0000000..1374766 --- /dev/null +++ b/include/mercury/kernel/storage.hpp @@ -0,0 +1,130 @@ +#ifndef MERCURY_KERNEL_STORAGE_HPP +#define MERCURY_KERNEL_STORAGE_HPP + +#include <mercury/kernel/utility.hpp> +#include <cstdint> + +namespace mercury::kernel::storage { + + typedef uint64_t node_id_t; + typedef uint64_t directory_iter_t; + + enum file_type { + regular_file, + directory, + symlink + }; + + enum io_result { + success, + mount_point_already_used, + not_a_directory, + not_supported, + out_of_bounds, + device_error, + fs_corrupt, + not_found, + bad_path, + }; + + class file_system_instance { + + public: + virtual ~file_system_instance() {} + + virtual io_result get_root_node(node_id_t &out) = 0; + + //get_first_child sets iter_out to a "directory iterator" representing the + //first child of this node. get_next_child gets the child after the child + //represented by the value of iter passed in, and changes iter to represent + //that next child. for an empty directory node, get_first_child returns + //io_result::out_of_bounds. when iter represents the last child of a node, + //get_next_child also returns io_result::out_of_bounds. + virtual io_result get_first_child(node_id_t node, node_id_t &out, directory_iter_t &iter_out) = 0; + virtual io_result get_next_child(node_id_t node, node_id_t &out, directory_iter_t &iter) = 0; + virtual io_result get_child(node_id_t node, node_id_t &out, const char *name, size_t name_len) = 0; + + virtual io_result get_name_length(node_id_t node, size_t &length_out) = 0; + //buffer is assumed to be long enough - call get_name_length first. + virtual io_result get_name(node_id_t node, char *buffer, size_t &length_out) = 0; + + virtual io_result get_file_length(node_id_t node, uint64_t &length_out) = 0; + + virtual io_result get_file_type(node_id_t node, file_type &out) = 0; + }; + + class block_device { + + private: + uint8_t *block_cache; + uint64_t block_cache_i; + bool block_cache_dirty; + + io_result load_cache_block(uint64_t i); + + protected: + //implemented in driver, bounds not checked + virtual io_result read_blocks_no_cache(uint64_t start, uint64_t count, void *into) = 0; + virtual io_result write_blocks_no_cache(uint64_t start, uint64_t count, const void *from) = 0; + + //it is assumed that this is only called once, by the driver, after + //block_size and block_count have been set, and before read_bytes or + //write_bytes can be called (e.g. in the derived class's constructor) + void allocate_block_cache(); + + public: + //set by storage component + file_system_instance *mounted_as; + utility::uuid id; + + //set by driver + uint64_t block_size; + uint64_t block_count; + + virtual ~block_device() { + if (block_cache) + delete block_cache; + } + + io_result read_bytes(uint64_t start, uint64_t count, void *into); + io_result write_bytes(uint64_t start, uint64_t count, const void *from); + + }; + + typedef io_result (*file_system_mounter)(block_device *bd, file_system_instance *&fs_out); + + extern utility::list<block_device *> *block_devices; + + void init_storage(); + + //a canon path contains no . or empty directory names, and + //contains no .. except for at the start of a relative path. + struct canon_path { + + bool absolute; + unsigned parent_count; + utility::vector<utility::string> segments; + + void parent(); + void rel(const canon_path &r); + + utility::string to_string(bool trailing_slash) const; + + }; + + void canonize_path(const char *str, size_t len, canon_path &out); + + //path must be absolute. + io_result mount_device(block_device *bd, const canon_path &path, file_system_mounter mounter); + + //path must be absolute. symlinks are always resolved on nodes other than the + //final one. they are resolved on the final node if and only if resolve final + //node is set to true. mount points are always traversed, including on the + //final node. this assumes that the path is under some mount point, and the + //same for any symlinks traversed (e.g. / is mounted). + io_result look_up_absolute_path(const canon_path &path, block_device *&bd_out, + node_id_t &node_out, bool resolve_final_node, canon_path &path_without_symlinks_out); + +} + +#endif diff --git a/include/mercury/kernel/terminal.hpp b/include/mercury/kernel/terminal.hpp index b9d9976..776ff64 100644 --- a/include/mercury/kernel/terminal.hpp +++ b/include/mercury/kernel/terminal.hpp @@ -1,6 +1,7 @@ #ifndef MERCURY_KERNEL_TERMINAL_HPP #define MERCURY_KERNEL_TERMINAL_HPP +#include <cstddef> #include <cstdint> namespace mercury::kernel::terminal { @@ -20,7 +21,7 @@ namespace mercury::kernel::terminal { extern framebuffer::color fg_color; void put_char(char ch); - + void put_string(const char *str, size_t len); void put_string_sz(const char *str); void put_int_decimal(uint64_t n, bool with_commas = true); diff --git a/include/mercury/kernel/utility.hpp b/include/mercury/kernel/utility.hpp index dbf0cf9..f12101a 100644 --- a/include/mercury/kernel/utility.hpp +++ b/include/mercury/kernel/utility.hpp @@ -20,101 +20,232 @@ namespace mercury::kernel::utility { uint8_t bytes[16]; }; + //if c appears in str, this returns the index of the first time it appears. + //otherwise, this returns len. + static inline unsigned find(const char *str, unsigned len, char c) { + for (unsigned i = 0; i < len; ++i) + if (str[i] == c) + return i; + return len; + } + template <class value_t> - struct string_tree { + struct list { - std::optional<value_t> value_here = {}; - string_tree<value_t> *parent = 0; - string_tree<value_t> *subtrees[256] = {}; + struct node { + value_t value; + node *next; + node *prev; + }; - //if there is a node whose key has a prefix in common with str, then this - //returns the deepest such node, and sets leftover_out to point to the - //character of str after the common prefix with that returned node. if - //there is no such node, this returns the current node and sets - //leftover_out to a null pointer. - string_tree &max_common_prefix( - const char *str, size_t str_len, const char *&leftover_out) { + node *first; + node *last; - string_tree<value_t> *last_with_value = 0; - const char *leftover_at_last_with_value = 0; - string_tree<value_t> *on = this; - size_t len_so_far = 0; + list() : first(0), last(0) {} - while (true) { + ~list() { + if (first) { + for (node *n = first->next; n; n = n->next) + delete n->prev; + delete last; + } + } - if (on->value_here) { - last_with_value = on; - leftover_at_last_with_value = str + len_so_far; - } + void insert_end(const value_t &value) { + node *n = new node {}; + n->value = value; + n->next = 0; + n->prev = last; + last = n; + } - if (len_so_far == str_len) - break; + void insert_end(value_t &&value) { + node *n = new node {}; + n->value = value; + n->next = 0; + n->prev = last; + last = n; + } - on = on->subtrees[(uint8_t)str[len_so_far]]; - if (!on) - break; + void clear() { + for (node *n = first; n; n = n->next) + delete n; + first = 0; + last = 0; + } - ++len_so_far; + //assumes there is a last. + void remove_last() { + node *new_last = last->prev; + if (new_last) + new_last->next = 0; + else + first = 0; + delete last; + last = new_last; + } - } + }; - if (last_with_value) { - leftover_out = leftover_at_last_with_value; - return *last_with_value; - } + template <class value_t> + struct vector { - leftover_out = 0; - return *this; + value_t *buffer; + unsigned buffer_len; + unsigned count; + + vector(unsigned buffer_len = 16) + : buffer(new value_t[buffer_len]), buffer_len(buffer_len), count(0) {} + vector(const value_t *copy_from, unsigned len) + : buffer(new value_t[len]), buffer_len(len), count(len) { + for (unsigned i = 0; i < len; ++i) + buffer[i] = copy_from[i]; } - bool try_insert(const char *str, size_t str_len, value_t value) { + ~vector() { + if (buffer) + delete[] buffer; + } - string_tree<value_t> *on = this; - for (size_t i = 0; i < str_len; ++i) { - string_tree<value_t> *&subtree = on->subtrees[(uint8_t)str[i]]; - if (!subtree) { - subtree = new string_tree<value_t>(); - subtree->parent = on; - } - on = subtree; - } + vector<value_t> &operator =(const vector<value_t> &other) { + if (buffer) + delete[] buffer; + buffer = new value_t[other.buffer_len]; + buffer_len = other.buffer_len; + for (unsigned i = 0; i < other.count; ++i) + buffer[i] = other.buffer[i]; + return *this; + } - if (on->value_here) + vector<value_t> &operator =(vector<value_t> &&other) { + if (buffer) + delete[] buffer; + buffer = other.buffer; + buffer_len = other.buffer_len; + count = other.count; + other.buffer = 0; + return *this; + } + + bool operator ==(const vector<value_t> &other) { + if (other.count != count) return false; - on->value_here = value; + for (unsigned i = 0; i < count; ++i) + if (other.buffer[i] != buffer[i]) + return false; return true; + } + void verify_buffer_len(unsigned target_len) { + if (buffer_len >= target_len) + return; + unsigned new_buffer_len = buffer_len; + do + new_buffer_len *= 2; + while (new_buffer_len < target_len); + value_t *new_buffer = new value_t[new_buffer_len]; + for (unsigned i = 0; i < count; ++i) + new_buffer[i] = std::move(buffer[i]); + delete[] buffer; + buffer = new_buffer; + buffer_len = new_buffer_len; + } + + void add_end(value_t &&v) { + verify_buffer_len(count + 1); + buffer[count] = std::move(v); + ++count; + } + + void add_end(const value_t &v) { + verify_buffer_len(count + 1); + buffer[count] = v; + ++count; } }; - //if c appears in str, this returns the index of the first time it appears. - //otherwise, this returns len. - static inline size_t find(const char *str, size_t len, char c) { - for (size_t i = 0; i < len; ++i) - if (str[i] == c) - return i; - return len; - } + typedef vector<char> string; - template <class value_t> - struct flist { + template <class key_component_t, class value_t> + struct trie { - struct node { - value_t value; - node *next; + typedef vector<key_component_t> key_t; + + struct child { + key_component_t component; + trie tr; }; - node *first; + //really this should be a hashmap or something + vector<child> children; + + trie *try_get_child(const key_component_t &component) const { + for (unsigned i = 0; i < children.count; ++i) + if (children.buffer[i].component == component) + return &children.buffer[i].tr; + return 0; + } + + std::optional<value_t> value_here; + + trie() : children(0) {} - flist() : first(0) {} + //prefix length is in key components, with the root node having a prefix + //length of 0. if no prefix of key has a value, then this just returns the + //root node and sets prefix length to 0. + const trie &longest_prefix_with_value( + const key_t &key, unsigned &prefix_length_out + ) const { - void insert(value_t value) { - first = new node { - .value = value, - .next = first - }; + const trie *on = this; + unsigned with_i = 0; + + const trie *longest_found = this; + prefix_length_out = 0; + + while (true) { + if (with_i == key.count) + return *longest_found; + on = on->try_get_child(key.buffer[with_i]); + if (!on) + return *longest_found; + ++with_i; + if (on->value_here) { + longest_found = on; + prefix_length_out = with_i; + } + } + + } + + bool has_key(const key_t &key) { + const trie *on = this; + for (unsigned i = 0; i < key.count; ++i) { + on = on->try_get_child(key.buffer[i]); + if (!on) + return false; + } + return on->value_here.has_value(); + } + + //returns false if this key is already in use. + bool try_insert(const key_t &key, value_t value) { + trie *on = this; + for (unsigned i = 0; i < key.count; ++i) { + on = on->try_get_child(key.buffer[i]); + if (!on) { + child ch; + ch.component = key.buffer[i]; + on->children.add_end(std::move(ch)); + on = &on->children.buffer[on->children.count - 1].tr; + } + } + if (on->value_here) + return false; + *on->value_here = value; + return true; } }; |