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Rev | Author | Line No. | Line |
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2627 | jermar | 1 | /* |
2793 | jermar | 2 | * Copyright (c) 2008 Jakub Jermar |
2627 | jermar | 3 | * All rights reserved. |
4 | * |
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5 | * Redistribution and use in source and binary forms, with or without |
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6 | * modification, are permitted provided that the following conditions |
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7 | * are met: |
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8 | * |
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9 | * - Redistributions of source code must retain the above copyright |
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10 | * notice, this list of conditions and the following disclaimer. |
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11 | * - Redistributions in binary form must reproduce the above copyright |
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12 | * notice, this list of conditions and the following disclaimer in the |
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13 | * documentation and/or other materials provided with the distribution. |
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14 | * - The name of the author may not be used to endorse or promote products |
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15 | * derived from this software without specific prior written permission. |
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16 | * |
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17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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27 | */ |
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28 | |||
29 | /** @addtogroup fs |
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30 | * @{ |
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31 | */ |
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32 | |||
33 | /** |
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34 | * @file fat_ops.c |
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35 | * @brief Implementation of VFS operations for the FAT file system server. |
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36 | */ |
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37 | |||
38 | #include "fat.h" |
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3505 | jermar | 39 | #include "fat_dentry.h" |
40 | #include "fat_fat.h" |
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2638 | jermar | 41 | #include "../../vfs/vfs.h" |
2793 | jermar | 42 | #include <libfs.h> |
3521 | jermar | 43 | #include <libblock.h> |
2627 | jermar | 44 | #include <ipc/ipc.h> |
3257 | jermar | 45 | #include <ipc/services.h> |
46 | #include <ipc/devmap.h> |
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2627 | jermar | 47 | #include <async.h> |
48 | #include <errno.h> |
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2793 | jermar | 49 | #include <string.h> |
2798 | jermar | 50 | #include <byteorder.h> |
2831 | jermar | 51 | #include <libadt/hash_table.h> |
52 | #include <libadt/list.h> |
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53 | #include <assert.h> |
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2856 | jermar | 54 | #include <futex.h> |
3257 | jermar | 55 | #include <sys/mman.h> |
3499 | jermar | 56 | #include <align.h> |
2627 | jermar | 57 | |
4357 | jermar | 58 | #define FAT_NODE(node) ((node) ? (fat_node_t *) (node)->data : NULL) |
59 | #define FS_NODE(node) ((node) ? (node)->bp : NULL) |
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60 | |||
2951 | jermar | 61 | /** Futex protecting the list of cached free FAT nodes. */ |
62 | static futex_t ffn_futex = FUTEX_INITIALIZER; |
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2843 | jermar | 63 | |
2951 | jermar | 64 | /** List of cached free FAT nodes. */ |
65 | static LIST_INITIALIZE(ffn_head); |
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66 | |||
2831 | jermar | 67 | static void fat_node_initialize(fat_node_t *node) |
2793 | jermar | 68 | { |
2951 | jermar | 69 | futex_initialize(&node->lock, 1); |
4357 | jermar | 70 | node->bp = NULL; |
2864 | jermar | 71 | node->idx = NULL; |
2831 | jermar | 72 | node->type = 0; |
73 | link_initialize(&node->ffn_link); |
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74 | node->size = 0; |
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75 | node->lnkcnt = 0; |
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76 | node->refcnt = 0; |
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77 | node->dirty = false; |
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2793 | jermar | 78 | } |
79 | |||
2893 | jermar | 80 | static void fat_node_sync(fat_node_t *node) |
2831 | jermar | 81 | { |
3530 | jermar | 82 | block_t *b; |
83 | fat_bs_t *bs; |
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3519 | jermar | 84 | fat_dentry_t *d; |
85 | uint16_t bps; |
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86 | unsigned dps; |
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87 | |||
88 | assert(node->dirty); |
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89 | |||
3530 | jermar | 90 | bs = block_bb_get(node->idx->dev_handle); |
91 | bps = uint16_t_le2host(bs->bps); |
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3519 | jermar | 92 | dps = bps / sizeof(fat_dentry_t); |
93 | |||
94 | /* Read the block that contains the dentry of interest. */ |
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3530 | jermar | 95 | b = _fat_block_get(bs, node->idx->dev_handle, node->idx->pfc, |
3595 | jermar | 96 | (node->idx->pdi * sizeof(fat_dentry_t)) / bps, BLOCK_FLAGS_NONE); |
3519 | jermar | 97 | |
98 | d = ((fat_dentry_t *)b->data) + (node->idx->pdi % dps); |
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99 | |||
100 | d->firstc = host2uint16_t_le(node->firstc); |
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3629 | jermar | 101 | if (node->type == FAT_FILE) { |
3519 | jermar | 102 | d->size = host2uint32_t_le(node->size); |
3629 | jermar | 103 | } else if (node->type == FAT_DIRECTORY) { |
104 | d->attr = FAT_ATTR_SUBDIR; |
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105 | } |
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3519 | jermar | 106 | |
3629 | jermar | 107 | /* TODO: update other fields? (e.g time fields) */ |
108 | |||
3519 | jermar | 109 | b->dirty = true; /* need to sync block */ |
110 | block_put(b); |
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2831 | jermar | 111 | } |
112 | |||
3574 | jermar | 113 | static fat_node_t *fat_node_get_new(void) |
114 | { |
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4357 | jermar | 115 | fs_node_t *fn; |
3574 | jermar | 116 | fat_node_t *nodep; |
117 | |||
118 | futex_down(&ffn_futex); |
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119 | if (!list_empty(&ffn_head)) { |
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120 | /* Try to use a cached free node structure. */ |
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121 | fat_idx_t *idxp_tmp; |
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122 | nodep = list_get_instance(ffn_head.next, fat_node_t, ffn_link); |
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123 | if (futex_trydown(&nodep->lock) == ESYNCH_WOULD_BLOCK) |
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124 | goto skip_cache; |
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125 | idxp_tmp = nodep->idx; |
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126 | if (futex_trydown(&idxp_tmp->lock) == ESYNCH_WOULD_BLOCK) { |
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127 | futex_up(&nodep->lock); |
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128 | goto skip_cache; |
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129 | } |
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130 | list_remove(&nodep->ffn_link); |
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131 | futex_up(&ffn_futex); |
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132 | if (nodep->dirty) |
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133 | fat_node_sync(nodep); |
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134 | idxp_tmp->nodep = NULL; |
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135 | futex_up(&nodep->lock); |
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136 | futex_up(&idxp_tmp->lock); |
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4357 | jermar | 137 | fn = FS_NODE(nodep); |
3574 | jermar | 138 | } else { |
139 | skip_cache: |
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140 | /* Try to allocate a new node structure. */ |
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141 | futex_up(&ffn_futex); |
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4357 | jermar | 142 | fn = (fs_node_t *)malloc(sizeof(fs_node_t)); |
143 | if (!fn) |
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144 | return NULL; |
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3574 | jermar | 145 | nodep = (fat_node_t *)malloc(sizeof(fat_node_t)); |
4357 | jermar | 146 | if (!nodep) { |
147 | free(fn); |
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3574 | jermar | 148 | return NULL; |
4357 | jermar | 149 | } |
3574 | jermar | 150 | } |
151 | fat_node_initialize(nodep); |
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4409 | jermar | 152 | fs_node_initialize(fn); |
4357 | jermar | 153 | fn->data = nodep; |
154 | nodep->bp = fn; |
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3574 | jermar | 155 | |
156 | return nodep; |
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157 | } |
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158 | |||
2951 | jermar | 159 | /** Internal version of fat_node_get(). |
160 | * |
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161 | * @param idxp Locked index structure. |
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162 | */ |
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4357 | jermar | 163 | static fat_node_t *fat_node_get_core(fat_idx_t *idxp) |
2831 | jermar | 164 | { |
3530 | jermar | 165 | block_t *b; |
166 | fat_bs_t *bs; |
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2891 | jermar | 167 | fat_dentry_t *d; |
3312 | jermar | 168 | fat_node_t *nodep = NULL; |
2891 | jermar | 169 | unsigned bps; |
3550 | jermar | 170 | unsigned spc; |
2891 | jermar | 171 | unsigned dps; |
172 | |||
2951 | jermar | 173 | if (idxp->nodep) { |
2891 | jermar | 174 | /* |
175 | * We are lucky. |
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176 | * The node is already instantiated in memory. |
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177 | */ |
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2951 | jermar | 178 | futex_down(&idxp->nodep->lock); |
179 | if (!idxp->nodep->refcnt++) |
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3312 | jermar | 180 | list_remove(&idxp->nodep->ffn_link); |
2951 | jermar | 181 | futex_up(&idxp->nodep->lock); |
182 | return idxp->nodep; |
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2891 | jermar | 183 | } |
184 | |||
185 | /* |
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186 | * We must instantiate the node from the file system. |
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187 | */ |
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188 | |||
2951 | jermar | 189 | assert(idxp->pfc); |
2891 | jermar | 190 | |
3574 | jermar | 191 | nodep = fat_node_get_new(); |
192 | if (!nodep) |
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193 | return NULL; |
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2891 | jermar | 194 | |
3530 | jermar | 195 | bs = block_bb_get(idxp->dev_handle); |
196 | bps = uint16_t_le2host(bs->bps); |
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3550 | jermar | 197 | spc = bs->spc; |
2891 | jermar | 198 | dps = bps / sizeof(fat_dentry_t); |
199 | |||
2893 | jermar | 200 | /* Read the block that contains the dentry of interest. */ |
3530 | jermar | 201 | b = _fat_block_get(bs, idxp->dev_handle, idxp->pfc, |
3595 | jermar | 202 | (idxp->pdi * sizeof(fat_dentry_t)) / bps, BLOCK_FLAGS_NONE); |
2891 | jermar | 203 | assert(b); |
204 | |||
2951 | jermar | 205 | d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps); |
2893 | jermar | 206 | if (d->attr & FAT_ATTR_SUBDIR) { |
207 | /* |
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208 | * The only directory which does not have this bit set is the |
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209 | * root directory itself. The root directory node is handled |
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210 | * and initialized elsewhere. |
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211 | */ |
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212 | nodep->type = FAT_DIRECTORY; |
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3282 | jermar | 213 | /* |
3325 | jermar | 214 | * Unfortunately, the 'size' field of the FAT dentry is not |
215 | * defined for the directory entry type. We must determine the |
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216 | * size of the directory by walking the FAT. |
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3282 | jermar | 217 | */ |
3550 | jermar | 218 | nodep->size = bps * spc * fat_clusters_get(bs, idxp->dev_handle, |
219 | uint16_t_le2host(d->firstc)); |
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2893 | jermar | 220 | } else { |
221 | nodep->type = FAT_FILE; |
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3282 | jermar | 222 | nodep->size = uint32_t_le2host(d->size); |
2893 | jermar | 223 | } |
224 | nodep->firstc = uint16_t_le2host(d->firstc); |
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225 | nodep->lnkcnt = 1; |
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226 | nodep->refcnt = 1; |
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227 | |||
228 | block_put(b); |
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229 | |||
230 | /* Link the idx structure with the node structure. */ |
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2951 | jermar | 231 | nodep->idx = idxp; |
232 | idxp->nodep = nodep; |
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2893 | jermar | 233 | |
234 | return nodep; |
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2831 | jermar | 235 | } |
236 | |||
3621 | jermar | 237 | /* |
238 | * Forward declarations of FAT libfs operations. |
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239 | */ |
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4357 | jermar | 240 | static fs_node_t *fat_node_get(dev_handle_t, fs_index_t); |
241 | static void fat_node_put(fs_node_t *); |
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242 | static fs_node_t *fat_create_node(dev_handle_t, int); |
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243 | static int fat_destroy_node(fs_node_t *); |
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244 | static int fat_link(fs_node_t *, fs_node_t *, const char *); |
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4370 | jermar | 245 | static int fat_unlink(fs_node_t *, fs_node_t *, const char *); |
4357 | jermar | 246 | static fs_node_t *fat_match(fs_node_t *, const char *); |
247 | static fs_index_t fat_index_get(fs_node_t *); |
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248 | static size_t fat_size_get(fs_node_t *); |
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249 | static unsigned fat_lnkcnt_get(fs_node_t *); |
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250 | static bool fat_has_children(fs_node_t *); |
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251 | static fs_node_t *fat_root_get(dev_handle_t); |
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3621 | jermar | 252 | static char fat_plb_get_char(unsigned); |
4357 | jermar | 253 | static bool fat_is_directory(fs_node_t *); |
254 | static bool fat_is_file(fs_node_t *node); |
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3621 | jermar | 255 | |
256 | /* |
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257 | * FAT libfs operations. |
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258 | */ |
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259 | |||
2951 | jermar | 260 | /** Instantiate a FAT in-core node. */ |
4357 | jermar | 261 | fs_node_t *fat_node_get(dev_handle_t dev_handle, fs_index_t index) |
2951 | jermar | 262 | { |
4357 | jermar | 263 | fat_node_t *nodep; |
2951 | jermar | 264 | fat_idx_t *idxp; |
265 | |||
266 | idxp = fat_idx_get_by_index(dev_handle, index); |
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267 | if (!idxp) |
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268 | return NULL; |
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269 | /* idxp->lock held */ |
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4357 | jermar | 270 | nodep = fat_node_get_core(idxp); |
2951 | jermar | 271 | futex_up(&idxp->lock); |
4357 | jermar | 272 | return FS_NODE(nodep); |
2951 | jermar | 273 | } |
274 | |||
4357 | jermar | 275 | void fat_node_put(fs_node_t *fn) |
2852 | jermar | 276 | { |
4357 | jermar | 277 | fat_node_t *nodep = FAT_NODE(fn); |
3609 | jermar | 278 | bool destroy = false; |
2910 | jermar | 279 | |
2951 | jermar | 280 | futex_down(&nodep->lock); |
2910 | jermar | 281 | if (!--nodep->refcnt) { |
3609 | jermar | 282 | if (nodep->idx) { |
283 | futex_down(&ffn_futex); |
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284 | list_append(&nodep->ffn_link, &ffn_head); |
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285 | futex_up(&ffn_futex); |
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286 | } else { |
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287 | /* |
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288 | * The node does not have any index structure associated |
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289 | * with itself. This can only mean that we are releasing |
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290 | * the node after a failed attempt to allocate the index |
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291 | * structure for it. |
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292 | */ |
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293 | destroy = true; |
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294 | } |
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2910 | jermar | 295 | } |
2951 | jermar | 296 | futex_up(&nodep->lock); |
4357 | jermar | 297 | if (destroy) { |
298 | free(nodep->bp); |
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299 | free(nodep); |
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300 | } |
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2852 | jermar | 301 | } |
302 | |||
4357 | jermar | 303 | fs_node_t *fat_create_node(dev_handle_t dev_handle, int flags) |
2857 | jermar | 304 | { |
3609 | jermar | 305 | fat_idx_t *idxp; |
306 | fat_node_t *nodep; |
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3633 | jermar | 307 | fat_bs_t *bs; |
308 | fat_cluster_t mcl, lcl; |
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309 | uint16_t bps; |
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310 | int rc; |
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3609 | jermar | 311 | |
3633 | jermar | 312 | bs = block_bb_get(dev_handle); |
313 | bps = uint16_t_le2host(bs->bps); |
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314 | if (flags & L_DIRECTORY) { |
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315 | /* allocate a cluster */ |
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316 | rc = fat_alloc_clusters(bs, dev_handle, 1, &mcl, &lcl); |
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317 | if (rc != EOK) |
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318 | return NULL; |
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319 | } |
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320 | |||
3609 | jermar | 321 | nodep = fat_node_get_new(); |
3633 | jermar | 322 | if (!nodep) { |
323 | fat_free_clusters(bs, dev_handle, mcl); |
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3609 | jermar | 324 | return NULL; |
3633 | jermar | 325 | } |
3609 | jermar | 326 | idxp = fat_idx_get_new(dev_handle); |
327 | if (!idxp) { |
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3633 | jermar | 328 | fat_free_clusters(bs, dev_handle, mcl); |
4357 | jermar | 329 | fat_node_put(FS_NODE(nodep)); |
3609 | jermar | 330 | return NULL; |
331 | } |
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332 | /* idxp->lock held */ |
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333 | if (flags & L_DIRECTORY) { |
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3633 | jermar | 334 | int i; |
335 | block_t *b; |
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336 | |||
337 | /* |
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338 | * Populate the new cluster with unused dentries. |
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339 | */ |
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340 | for (i = 0; i < bs->spc; i++) { |
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341 | b = _fat_block_get(bs, dev_handle, mcl, i, |
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342 | BLOCK_FLAGS_NOREAD); |
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343 | /* mark all dentries as never-used */ |
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344 | memset(b->data, 0, bps); |
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345 | b->dirty = false; |
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346 | block_put(b); |
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347 | } |
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3609 | jermar | 348 | nodep->type = FAT_DIRECTORY; |
3633 | jermar | 349 | nodep->firstc = mcl; |
350 | nodep->size = bps * bs->spc; |
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3609 | jermar | 351 | } else { |
352 | nodep->type = FAT_FILE; |
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3633 | jermar | 353 | nodep->firstc = FAT_CLST_RES0; |
354 | nodep->size = 0; |
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3609 | jermar | 355 | } |
356 | nodep->lnkcnt = 0; /* not linked anywhere */ |
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357 | nodep->refcnt = 1; |
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3633 | jermar | 358 | nodep->dirty = true; |
3609 | jermar | 359 | |
360 | nodep->idx = idxp; |
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361 | idxp->nodep = nodep; |
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362 | |||
363 | futex_up(&idxp->lock); |
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4357 | jermar | 364 | return FS_NODE(nodep); |
2857 | jermar | 365 | } |
366 | |||
4357 | jermar | 367 | int fat_destroy_node(fs_node_t *fn) |
2857 | jermar | 368 | { |
4357 | jermar | 369 | fat_node_t *nodep = FAT_NODE(fn); |
3621 | jermar | 370 | fat_bs_t *bs; |
371 | |||
372 | /* |
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373 | * The node is not reachable from the file system. This means that the |
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374 | * link count should be zero and that the index structure cannot be |
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375 | * found in the position hash. Obviously, we don't need to lock the node |
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376 | * nor its index structure. |
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377 | */ |
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378 | assert(nodep->lnkcnt == 0); |
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379 | |||
380 | /* |
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381 | * The node may not have any children. |
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382 | */ |
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4357 | jermar | 383 | assert(fat_has_children(fn) == false); |
3621 | jermar | 384 | |
385 | bs = block_bb_get(nodep->idx->dev_handle); |
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386 | if (nodep->firstc != FAT_CLST_RES0) { |
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387 | assert(nodep->size); |
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388 | /* Free all clusters allocated to the node. */ |
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389 | fat_free_clusters(bs, nodep->idx->dev_handle, nodep->firstc); |
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390 | } |
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391 | |||
392 | fat_idx_destroy(nodep->idx); |
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4357 | jermar | 393 | free(nodep->bp); |
3621 | jermar | 394 | free(nodep); |
395 | return EOK; |
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2857 | jermar | 396 | } |
397 | |||
4357 | jermar | 398 | int fat_link(fs_node_t *pfn, fs_node_t *cfn, const char *name) |
2857 | jermar | 399 | { |
4357 | jermar | 400 | fat_node_t *parentp = FAT_NODE(pfn); |
401 | fat_node_t *childp = FAT_NODE(cfn); |
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3628 | jermar | 402 | fat_dentry_t *d; |
403 | fat_bs_t *bs; |
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404 | block_t *b; |
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405 | int i, j; |
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406 | uint16_t bps; |
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407 | unsigned dps; |
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408 | unsigned blocks; |
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3700 | jermar | 409 | fat_cluster_t mcl, lcl; |
410 | int rc; |
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3628 | jermar | 411 | |
412 | futex_down(&childp->lock); |
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413 | if (childp->lnkcnt == 1) { |
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414 | /* |
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415 | * On FAT, we don't support multiple hard links. |
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416 | */ |
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417 | futex_up(&childp->lock); |
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418 | return EMLINK; |
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419 | } |
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420 | assert(childp->lnkcnt == 0); |
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421 | futex_up(&childp->lock); |
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422 | |||
423 | if (!fat_dentry_name_verify(name)) { |
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424 | /* |
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425 | * Attempt to create unsupported name. |
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426 | */ |
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427 | return ENOTSUP; |
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428 | } |
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429 | |||
430 | /* |
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431 | * Get us an unused parent node's dentry or grow the parent and allocate |
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432 | * a new one. |
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433 | */ |
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434 | |||
435 | futex_down(&parentp->idx->lock); |
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436 | bs = block_bb_get(parentp->idx->dev_handle); |
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437 | bps = uint16_t_le2host(bs->bps); |
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438 | dps = bps / sizeof(fat_dentry_t); |
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439 | |||
440 | blocks = parentp->size / bps; |
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441 | |||
442 | for (i = 0; i < blocks; i++) { |
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443 | b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE); |
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444 | for (j = 0; j < dps; j++) { |
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445 | d = ((fat_dentry_t *)b->data) + j; |
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446 | switch (fat_classify_dentry(d)) { |
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447 | case FAT_DENTRY_SKIP: |
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448 | case FAT_DENTRY_VALID: |
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449 | /* skipping used and meta entries */ |
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450 | continue; |
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451 | case FAT_DENTRY_FREE: |
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452 | case FAT_DENTRY_LAST: |
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453 | /* found an empty slot */ |
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454 | goto hit; |
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455 | } |
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456 | } |
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457 | block_put(b); |
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458 | } |
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3701 | jermar | 459 | j = 0; |
3628 | jermar | 460 | |
461 | /* |
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462 | * We need to grow the parent in order to create a new unused dentry. |
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463 | */ |
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3700 | jermar | 464 | if (parentp->idx->pfc == FAT_CLST_ROOT) { |
465 | /* Can't grow the root directory. */ |
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466 | futex_up(&parentp->idx->lock); |
||
467 | return ENOSPC; |
||
468 | } |
||
469 | rc = fat_alloc_clusters(bs, parentp->idx->dev_handle, 1, &mcl, &lcl); |
||
470 | if (rc != EOK) { |
||
471 | futex_up(&parentp->idx->lock); |
||
472 | return rc; |
||
473 | } |
||
474 | fat_append_clusters(bs, parentp, mcl); |
||
475 | b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NOREAD); |
||
476 | d = (fat_dentry_t *)b->data; |
||
477 | /* |
||
478 | * Clear all dentries in the block except for the first one (the first |
||
479 | * dentry will be cleared in the next step). |
||
480 | */ |
||
481 | memset(d + 1, 0, bps - sizeof(fat_dentry_t)); |
||
3628 | jermar | 482 | |
483 | hit: |
||
484 | /* |
||
485 | * At this point we only establish the link between the parent and the |
||
486 | * child. The dentry, except of the name and the extension, will remain |
||
3700 | jermar | 487 | * uninitialized until the corresponding node is synced. Thus the valid |
488 | * dentry data is kept in the child node structure. |
||
3628 | jermar | 489 | */ |
490 | memset(d, 0, sizeof(fat_dentry_t)); |
||
491 | fat_dentry_name_set(d, name); |
||
492 | b->dirty = true; /* need to sync block */ |
||
493 | block_put(b); |
||
494 | futex_up(&parentp->idx->lock); |
||
495 | |||
496 | futex_down(&childp->idx->lock); |
||
3660 | jermar | 497 | |
498 | /* |
||
499 | * If possible, create the Sub-directory Identifier Entry and the |
||
500 | * Sub-directory Parent Pointer Entry (i.e. "." and ".."). These entries |
||
501 | * are not mandatory according to Standard ECMA-107 and HelenOS VFS does |
||
502 | * not use them anyway, so this is rather a sign of our good will. |
||
503 | */ |
||
504 | b = fat_block_get(bs, childp, 0, BLOCK_FLAGS_NONE); |
||
505 | d = (fat_dentry_t *)b->data; |
||
506 | if (fat_classify_dentry(d) == FAT_DENTRY_LAST || |
||
4264 | svoboda | 507 | str_cmp(d->name, FAT_NAME_DOT) == 0) { |
3660 | jermar | 508 | memset(d, 0, sizeof(fat_dentry_t)); |
4268 | svoboda | 509 | str_cpy(d->name, 8, FAT_NAME_DOT); |
510 | str_cpy(d->ext, 3, FAT_EXT_PAD); |
||
3660 | jermar | 511 | d->attr = FAT_ATTR_SUBDIR; |
512 | d->firstc = host2uint16_t_le(childp->firstc); |
||
513 | /* TODO: initialize also the date/time members. */ |
||
514 | } |
||
515 | d++; |
||
516 | if (fat_classify_dentry(d) == FAT_DENTRY_LAST || |
||
4264 | svoboda | 517 | str_cmp(d->name, FAT_NAME_DOT_DOT) == 0) { |
3660 | jermar | 518 | memset(d, 0, sizeof(fat_dentry_t)); |
4268 | svoboda | 519 | str_cpy(d->name, 8, FAT_NAME_DOT_DOT); |
520 | str_cpy(d->ext, 3, FAT_EXT_PAD); |
||
3660 | jermar | 521 | d->attr = FAT_ATTR_SUBDIR; |
522 | d->firstc = (parentp->firstc == FAT_CLST_ROOT) ? |
||
523 | host2uint16_t_le(FAT_CLST_RES0) : |
||
524 | host2uint16_t_le(parentp->firstc); |
||
525 | /* TODO: initialize also the date/time members. */ |
||
526 | } |
||
527 | b->dirty = true; /* need to sync block */ |
||
528 | block_put(b); |
||
529 | |||
3628 | jermar | 530 | childp->idx->pfc = parentp->firstc; |
531 | childp->idx->pdi = i * dps + j; |
||
532 | futex_up(&childp->idx->lock); |
||
533 | |||
534 | futex_down(&childp->lock); |
||
535 | childp->lnkcnt = 1; |
||
536 | childp->dirty = true; /* need to sync node */ |
||
537 | futex_up(&childp->lock); |
||
538 | |||
539 | /* |
||
540 | * Hash in the index structure into the position hash. |
||
541 | */ |
||
542 | fat_idx_hashin(childp->idx); |
||
543 | |||
544 | return EOK; |
||
2857 | jermar | 545 | } |
546 | |||
4370 | jermar | 547 | int fat_unlink(fs_node_t *pfn, fs_node_t *cfn, const char *nm) |
2857 | jermar | 548 | { |
4357 | jermar | 549 | fat_node_t *parentp = FAT_NODE(pfn); |
550 | fat_node_t *childp = FAT_NODE(cfn); |
||
3638 | jermar | 551 | fat_bs_t *bs; |
552 | fat_dentry_t *d; |
||
553 | uint16_t bps; |
||
554 | block_t *b; |
||
555 | |||
4358 | jermar | 556 | if (!parentp) |
557 | return EBUSY; |
||
4359 | jermar | 558 | |
559 | if (fat_has_children(cfn)) |
||
560 | return ENOTEMPTY; |
||
4358 | jermar | 561 | |
3638 | jermar | 562 | futex_down(&parentp->lock); |
563 | futex_down(&childp->lock); |
||
564 | assert(childp->lnkcnt == 1); |
||
565 | futex_down(&childp->idx->lock); |
||
566 | bs = block_bb_get(childp->idx->dev_handle); |
||
567 | bps = uint16_t_le2host(bs->bps); |
||
568 | |||
569 | b = _fat_block_get(bs, childp->idx->dev_handle, childp->idx->pfc, |
||
570 | (childp->idx->pdi * sizeof(fat_dentry_t)) / bps, |
||
571 | BLOCK_FLAGS_NONE); |
||
572 | d = (fat_dentry_t *)b->data + |
||
573 | (childp->idx->pdi % (bps / sizeof(fat_dentry_t))); |
||
574 | /* mark the dentry as not-currently-used */ |
||
575 | d->name[0] = FAT_DENTRY_ERASED; |
||
576 | b->dirty = true; /* need to sync block */ |
||
577 | block_put(b); |
||
578 | |||
579 | /* remove the index structure from the position hash */ |
||
580 | fat_idx_hashout(childp->idx); |
||
581 | /* clear position information */ |
||
582 | childp->idx->pfc = FAT_CLST_RES0; |
||
583 | childp->idx->pdi = 0; |
||
584 | futex_up(&childp->idx->lock); |
||
585 | childp->lnkcnt = 0; |
||
586 | childp->dirty = true; |
||
587 | futex_up(&childp->lock); |
||
588 | futex_up(&parentp->lock); |
||
589 | |||
590 | return EOK; |
||
2857 | jermar | 591 | } |
592 | |||
4357 | jermar | 593 | fs_node_t *fat_match(fs_node_t *pfn, const char *component) |
2793 | jermar | 594 | { |
3530 | jermar | 595 | fat_bs_t *bs; |
4357 | jermar | 596 | fat_node_t *parentp = FAT_NODE(pfn); |
2793 | jermar | 597 | char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1]; |
2822 | jermar | 598 | unsigned i, j; |
2828 | jermar | 599 | unsigned bps; /* bytes per sector */ |
2822 | jermar | 600 | unsigned dps; /* dentries per sector */ |
601 | unsigned blocks; |
||
2793 | jermar | 602 | fat_dentry_t *d; |
3530 | jermar | 603 | block_t *b; |
2793 | jermar | 604 | |
2953 | jermar | 605 | futex_down(&parentp->idx->lock); |
3530 | jermar | 606 | bs = block_bb_get(parentp->idx->dev_handle); |
607 | bps = uint16_t_le2host(bs->bps); |
||
2828 | jermar | 608 | dps = bps / sizeof(fat_dentry_t); |
3526 | jermar | 609 | blocks = parentp->size / bps; |
2822 | jermar | 610 | for (i = 0; i < blocks; i++) { |
3595 | jermar | 611 | b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE); |
3526 | jermar | 612 | for (j = 0; j < dps; j++) { |
2822 | jermar | 613 | d = ((fat_dentry_t *)b->data) + j; |
2845 | jermar | 614 | switch (fat_classify_dentry(d)) { |
615 | case FAT_DENTRY_SKIP: |
||
3628 | jermar | 616 | case FAT_DENTRY_FREE: |
2822 | jermar | 617 | continue; |
2845 | jermar | 618 | case FAT_DENTRY_LAST: |
2822 | jermar | 619 | block_put(b); |
2953 | jermar | 620 | futex_up(&parentp->idx->lock); |
2822 | jermar | 621 | return NULL; |
2845 | jermar | 622 | default: |
623 | case FAT_DENTRY_VALID: |
||
3628 | jermar | 624 | fat_dentry_name_get(d, name); |
2845 | jermar | 625 | break; |
2822 | jermar | 626 | } |
3634 | jermar | 627 | if (fat_dentry_namecmp(name, component) == 0) { |
2822 | jermar | 628 | /* hit */ |
4357 | jermar | 629 | fat_node_t *nodep; |
2953 | jermar | 630 | /* |
631 | * Assume tree hierarchy for locking. We |
||
632 | * already have the parent and now we are going |
||
633 | * to lock the child. Never lock in the oposite |
||
634 | * order. |
||
635 | */ |
||
2890 | jermar | 636 | fat_idx_t *idx = fat_idx_get_by_pos( |
2881 | jermar | 637 | parentp->idx->dev_handle, parentp->firstc, |
2864 | jermar | 638 | i * dps + j); |
2953 | jermar | 639 | futex_up(&parentp->idx->lock); |
2890 | jermar | 640 | if (!idx) { |
641 | /* |
||
642 | * Can happen if memory is low or if we |
||
643 | * run out of 32-bit indices. |
||
644 | */ |
||
645 | block_put(b); |
||
646 | return NULL; |
||
647 | } |
||
4357 | jermar | 648 | nodep = fat_node_get_core(idx); |
2951 | jermar | 649 | futex_up(&idx->lock); |
2822 | jermar | 650 | block_put(b); |
4357 | jermar | 651 | return FS_NODE(nodep); |
2822 | jermar | 652 | } |
2793 | jermar | 653 | } |
2822 | jermar | 654 | block_put(b); |
2639 | jermar | 655 | } |
3516 | jermar | 656 | |
2953 | jermar | 657 | futex_up(&parentp->idx->lock); |
2793 | jermar | 658 | return NULL; |
2638 | jermar | 659 | } |
660 | |||
4357 | jermar | 661 | fs_index_t fat_index_get(fs_node_t *fn) |
2831 | jermar | 662 | { |
4357 | jermar | 663 | return FAT_NODE(fn)->idx->index; |
2831 | jermar | 664 | } |
665 | |||
4357 | jermar | 666 | size_t fat_size_get(fs_node_t *fn) |
2831 | jermar | 667 | { |
4357 | jermar | 668 | return FAT_NODE(fn)->size; |
2831 | jermar | 669 | } |
670 | |||
4357 | jermar | 671 | unsigned fat_lnkcnt_get(fs_node_t *fn) |
2831 | jermar | 672 | { |
4357 | jermar | 673 | return FAT_NODE(fn)->lnkcnt; |
2831 | jermar | 674 | } |
675 | |||
4357 | jermar | 676 | bool fat_has_children(fs_node_t *fn) |
2845 | jermar | 677 | { |
3530 | jermar | 678 | fat_bs_t *bs; |
4357 | jermar | 679 | fat_node_t *nodep = FAT_NODE(fn); |
2845 | jermar | 680 | unsigned bps; |
681 | unsigned dps; |
||
682 | unsigned blocks; |
||
3530 | jermar | 683 | block_t *b; |
2845 | jermar | 684 | unsigned i, j; |
685 | |||
686 | if (nodep->type != FAT_DIRECTORY) |
||
687 | return false; |
||
3526 | jermar | 688 | |
2951 | jermar | 689 | futex_down(&nodep->idx->lock); |
3530 | jermar | 690 | bs = block_bb_get(nodep->idx->dev_handle); |
691 | bps = uint16_t_le2host(bs->bps); |
||
2845 | jermar | 692 | dps = bps / sizeof(fat_dentry_t); |
693 | |||
3526 | jermar | 694 | blocks = nodep->size / bps; |
2845 | jermar | 695 | |
696 | for (i = 0; i < blocks; i++) { |
||
697 | fat_dentry_t *d; |
||
698 | |||
3595 | jermar | 699 | b = fat_block_get(bs, nodep, i, BLOCK_FLAGS_NONE); |
3526 | jermar | 700 | for (j = 0; j < dps; j++) { |
2845 | jermar | 701 | d = ((fat_dentry_t *)b->data) + j; |
702 | switch (fat_classify_dentry(d)) { |
||
703 | case FAT_DENTRY_SKIP: |
||
3628 | jermar | 704 | case FAT_DENTRY_FREE: |
2845 | jermar | 705 | continue; |
706 | case FAT_DENTRY_LAST: |
||
707 | block_put(b); |
||
2951 | jermar | 708 | futex_up(&nodep->idx->lock); |
2845 | jermar | 709 | return false; |
710 | default: |
||
711 | case FAT_DENTRY_VALID: |
||
712 | block_put(b); |
||
2951 | jermar | 713 | futex_up(&nodep->idx->lock); |
2845 | jermar | 714 | return true; |
715 | } |
||
716 | block_put(b); |
||
2951 | jermar | 717 | futex_up(&nodep->idx->lock); |
2845 | jermar | 718 | return true; |
719 | } |
||
720 | block_put(b); |
||
721 | } |
||
722 | |||
2951 | jermar | 723 | futex_up(&nodep->idx->lock); |
2845 | jermar | 724 | return false; |
725 | } |
||
726 | |||
4357 | jermar | 727 | fs_node_t *fat_root_get(dev_handle_t dev_handle) |
2844 | jermar | 728 | { |
3119 | jermar | 729 | return fat_node_get(dev_handle, 0); |
2844 | jermar | 730 | } |
731 | |||
3621 | jermar | 732 | char fat_plb_get_char(unsigned pos) |
2844 | jermar | 733 | { |
734 | return fat_reg.plb_ro[pos % PLB_SIZE]; |
||
735 | } |
||
736 | |||
4357 | jermar | 737 | bool fat_is_directory(fs_node_t *fn) |
2831 | jermar | 738 | { |
4357 | jermar | 739 | return FAT_NODE(fn)->type == FAT_DIRECTORY; |
2831 | jermar | 740 | } |
741 | |||
4357 | jermar | 742 | bool fat_is_file(fs_node_t *fn) |
2831 | jermar | 743 | { |
4357 | jermar | 744 | return FAT_NODE(fn)->type == FAT_FILE; |
2831 | jermar | 745 | } |
746 | |||
2793 | jermar | 747 | /** libfs operations */ |
748 | libfs_ops_t fat_libfs_ops = { |
||
749 | .match = fat_match, |
||
750 | .node_get = fat_node_get, |
||
2852 | jermar | 751 | .node_put = fat_node_put, |
3609 | jermar | 752 | .create = fat_create_node, |
753 | .destroy = fat_destroy_node, |
||
2857 | jermar | 754 | .link = fat_link, |
755 | .unlink = fat_unlink, |
||
2831 | jermar | 756 | .index_get = fat_index_get, |
757 | .size_get = fat_size_get, |
||
758 | .lnkcnt_get = fat_lnkcnt_get, |
||
2845 | jermar | 759 | .has_children = fat_has_children, |
2844 | jermar | 760 | .root_get = fat_root_get, |
761 | .plb_get_char = fat_plb_get_char, |
||
2831 | jermar | 762 | .is_directory = fat_is_directory, |
763 | .is_file = fat_is_file |
||
2793 | jermar | 764 | }; |
765 | |||
3625 | jermar | 766 | /* |
767 | * VFS operations. |
||
768 | */ |
||
769 | |||
3110 | jermar | 770 | void fat_mounted(ipc_callid_t rid, ipc_call_t *request) |
771 | { |
||
772 | dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request); |
||
3530 | jermar | 773 | fat_bs_t *bs; |
3257 | jermar | 774 | uint16_t bps; |
3119 | jermar | 775 | uint16_t rde; |
3110 | jermar | 776 | int rc; |
777 | |||
4305 | jermar | 778 | /* accept the mount options */ |
779 | ipc_callid_t callid; |
||
780 | size_t size; |
||
781 | if (!ipc_data_write_receive(&callid, &size)) { |
||
782 | ipc_answer_0(callid, EINVAL); |
||
783 | ipc_answer_0(rid, EINVAL); |
||
784 | return; |
||
785 | } |
||
786 | char *opts = malloc(size + 1); |
||
787 | if (!opts) { |
||
788 | ipc_answer_0(callid, ENOMEM); |
||
789 | ipc_answer_0(rid, ENOMEM); |
||
790 | return; |
||
791 | } |
||
792 | ipcarg_t retval = ipc_data_write_finalize(callid, opts, size); |
||
793 | if (retval != EOK) { |
||
794 | ipc_answer_0(rid, retval); |
||
795 | free(opts); |
||
796 | return; |
||
797 | } |
||
798 | opts[size] = '\0'; |
||
799 | |||
3530 | jermar | 800 | /* initialize libblock */ |
3537 | jermar | 801 | rc = block_init(dev_handle, BS_SIZE); |
3257 | jermar | 802 | if (rc != EOK) { |
3537 | jermar | 803 | ipc_answer_0(rid, rc); |
3257 | jermar | 804 | return; |
805 | } |
||
806 | |||
3537 | jermar | 807 | /* prepare the boot block */ |
808 | rc = block_bb_read(dev_handle, BS_BLOCK * BS_SIZE, BS_SIZE); |
||
809 | if (rc != EOK) { |
||
810 | block_fini(dev_handle); |
||
811 | ipc_answer_0(rid, rc); |
||
812 | return; |
||
813 | } |
||
814 | |||
3530 | jermar | 815 | /* get the buffer with the boot sector */ |
816 | bs = block_bb_get(dev_handle); |
||
817 | |||
3119 | jermar | 818 | /* Read the number of root directory entries. */ |
3530 | jermar | 819 | bps = uint16_t_le2host(bs->bps); |
820 | rde = uint16_t_le2host(bs->root_ent_max); |
||
3119 | jermar | 821 | |
3257 | jermar | 822 | if (bps != BS_SIZE) { |
3530 | jermar | 823 | block_fini(dev_handle); |
3257 | jermar | 824 | ipc_answer_0(rid, ENOTSUP); |
825 | return; |
||
826 | } |
||
827 | |||
3539 | jermar | 828 | /* Initialize the block cache */ |
829 | rc = block_cache_init(dev_handle, bps, 0 /* XXX */); |
||
830 | if (rc != EOK) { |
||
831 | block_fini(dev_handle); |
||
832 | ipc_answer_0(rid, rc); |
||
833 | return; |
||
834 | } |
||
835 | |||
3110 | jermar | 836 | rc = fat_idx_init_by_dev_handle(dev_handle); |
837 | if (rc != EOK) { |
||
3530 | jermar | 838 | block_fini(dev_handle); |
3110 | jermar | 839 | ipc_answer_0(rid, rc); |
840 | return; |
||
841 | } |
||
842 | |||
3119 | jermar | 843 | /* Initialize the root node. */ |
4357 | jermar | 844 | fs_node_t *rfn = (fs_node_t *)malloc(sizeof(fs_node_t)); |
845 | if (!rfn) { |
||
846 | block_fini(dev_handle); |
||
847 | fat_idx_fini_by_dev_handle(dev_handle); |
||
848 | ipc_answer_0(rid, ENOMEM); |
||
849 | return; |
||
850 | } |
||
4409 | jermar | 851 | fs_node_initialize(rfn); |
3119 | jermar | 852 | fat_node_t *rootp = (fat_node_t *)malloc(sizeof(fat_node_t)); |
853 | if (!rootp) { |
||
4357 | jermar | 854 | free(rfn); |
3530 | jermar | 855 | block_fini(dev_handle); |
3119 | jermar | 856 | fat_idx_fini_by_dev_handle(dev_handle); |
857 | ipc_answer_0(rid, ENOMEM); |
||
858 | return; |
||
859 | } |
||
860 | fat_node_initialize(rootp); |
||
861 | |||
862 | fat_idx_t *ridxp = fat_idx_get_by_pos(dev_handle, FAT_CLST_ROOTPAR, 0); |
||
863 | if (!ridxp) { |
||
4357 | jermar | 864 | free(rfn); |
865 | free(rootp); |
||
3530 | jermar | 866 | block_fini(dev_handle); |
3119 | jermar | 867 | fat_idx_fini_by_dev_handle(dev_handle); |
868 | ipc_answer_0(rid, ENOMEM); |
||
869 | return; |
||
870 | } |
||
871 | assert(ridxp->index == 0); |
||
872 | /* ridxp->lock held */ |
||
873 | |||
874 | rootp->type = FAT_DIRECTORY; |
||
875 | rootp->firstc = FAT_CLST_ROOT; |
||
876 | rootp->refcnt = 1; |
||
3352 | jermar | 877 | rootp->lnkcnt = 0; /* FS root is not linked */ |
3119 | jermar | 878 | rootp->size = rde * sizeof(fat_dentry_t); |
879 | rootp->idx = ridxp; |
||
880 | ridxp->nodep = rootp; |
||
4357 | jermar | 881 | rootp->bp = rfn; |
882 | rfn->data = rootp; |
||
3119 | jermar | 883 | |
884 | futex_up(&ridxp->lock); |
||
885 | |||
3352 | jermar | 886 | ipc_answer_3(rid, EOK, ridxp->index, rootp->size, rootp->lnkcnt); |
3110 | jermar | 887 | } |
888 | |||
889 | void fat_mount(ipc_callid_t rid, ipc_call_t *request) |
||
890 | { |
||
4429 | jermar | 891 | libfs_mount(&fat_libfs_ops, fat_reg.fs_handle, rid, request); |
3110 | jermar | 892 | } |
893 | |||
2627 | jermar | 894 | void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
895 | { |
||
2793 | jermar | 896 | libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request); |
2627 | jermar | 897 | } |
898 | |||
3307 | jermar | 899 | void fat_read(ipc_callid_t rid, ipc_call_t *request) |
900 | { |
||
901 | dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request); |
||
902 | fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request); |
||
903 | off_t pos = (off_t)IPC_GET_ARG3(*request); |
||
4357 | jermar | 904 | fs_node_t *fn = fat_node_get(dev_handle, index); |
905 | fat_node_t *nodep; |
||
3530 | jermar | 906 | fat_bs_t *bs; |
3516 | jermar | 907 | uint16_t bps; |
3308 | jermar | 908 | size_t bytes; |
3530 | jermar | 909 | block_t *b; |
3308 | jermar | 910 | |
4357 | jermar | 911 | if (!fn) { |
3307 | jermar | 912 | ipc_answer_0(rid, ENOENT); |
913 | return; |
||
914 | } |
||
4357 | jermar | 915 | nodep = FAT_NODE(fn); |
3307 | jermar | 916 | |
917 | ipc_callid_t callid; |
||
918 | size_t len; |
||
3314 | jermar | 919 | if (!ipc_data_read_receive(&callid, &len)) { |
4357 | jermar | 920 | fat_node_put(fn); |
3307 | jermar | 921 | ipc_answer_0(callid, EINVAL); |
922 | ipc_answer_0(rid, EINVAL); |
||
923 | return; |
||
924 | } |
||
925 | |||
3530 | jermar | 926 | bs = block_bb_get(dev_handle); |
927 | bps = uint16_t_le2host(bs->bps); |
||
3516 | jermar | 928 | |
3307 | jermar | 929 | if (nodep->type == FAT_FILE) { |
3335 | jermar | 930 | /* |
931 | * Our strategy for regular file reads is to read one block at |
||
932 | * most and make use of the possibility to return less data than |
||
933 | * requested. This keeps the code very simple. |
||
934 | */ |
||
3532 | jermar | 935 | if (pos >= nodep->size) { |
3533 | jermar | 936 | /* reading beyond the EOF */ |
937 | bytes = 0; |
||
3532 | jermar | 938 | (void) ipc_data_read_finalize(callid, NULL, 0); |
939 | } else { |
||
940 | bytes = min(len, bps - pos % bps); |
||
941 | bytes = min(bytes, nodep->size - pos); |
||
3595 | jermar | 942 | b = fat_block_get(bs, nodep, pos / bps, |
943 | BLOCK_FLAGS_NONE); |
||
3532 | jermar | 944 | (void) ipc_data_read_finalize(callid, b->data + pos % bps, |
945 | bytes); |
||
946 | block_put(b); |
||
947 | } |
||
3307 | jermar | 948 | } else { |
3335 | jermar | 949 | unsigned bnum; |
950 | off_t spos = pos; |
||
951 | char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1]; |
||
952 | fat_dentry_t *d; |
||
953 | |||
3307 | jermar | 954 | assert(nodep->type == FAT_DIRECTORY); |
3335 | jermar | 955 | assert(nodep->size % bps == 0); |
956 | assert(bps % sizeof(fat_dentry_t) == 0); |
||
957 | |||
958 | /* |
||
959 | * Our strategy for readdir() is to use the position pointer as |
||
960 | * an index into the array of all dentries. On entry, it points |
||
961 | * to the first unread dentry. If we skip any dentries, we bump |
||
962 | * the position pointer accordingly. |
||
963 | */ |
||
964 | bnum = (pos * sizeof(fat_dentry_t)) / bps; |
||
965 | while (bnum < nodep->size / bps) { |
||
966 | off_t o; |
||
967 | |||
3595 | jermar | 968 | b = fat_block_get(bs, nodep, bnum, BLOCK_FLAGS_NONE); |
3335 | jermar | 969 | for (o = pos % (bps / sizeof(fat_dentry_t)); |
970 | o < bps / sizeof(fat_dentry_t); |
||
971 | o++, pos++) { |
||
972 | d = ((fat_dentry_t *)b->data) + o; |
||
973 | switch (fat_classify_dentry(d)) { |
||
974 | case FAT_DENTRY_SKIP: |
||
3628 | jermar | 975 | case FAT_DENTRY_FREE: |
3335 | jermar | 976 | continue; |
977 | case FAT_DENTRY_LAST: |
||
978 | block_put(b); |
||
979 | goto miss; |
||
980 | default: |
||
981 | case FAT_DENTRY_VALID: |
||
3628 | jermar | 982 | fat_dentry_name_get(d, name); |
3335 | jermar | 983 | block_put(b); |
984 | goto hit; |
||
985 | } |
||
986 | } |
||
987 | block_put(b); |
||
988 | bnum++; |
||
989 | } |
||
990 | miss: |
||
4357 | jermar | 991 | fat_node_put(fn); |
3335 | jermar | 992 | ipc_answer_0(callid, ENOENT); |
993 | ipc_answer_1(rid, ENOENT, 0); |
||
3307 | jermar | 994 | return; |
3335 | jermar | 995 | hit: |
4264 | svoboda | 996 | (void) ipc_data_read_finalize(callid, name, str_size(name) + 1); |
3335 | jermar | 997 | bytes = (pos - spos) + 1; |
3307 | jermar | 998 | } |
999 | |||
4357 | jermar | 1000 | fat_node_put(fn); |
3308 | jermar | 1001 | ipc_answer_1(rid, EOK, (ipcarg_t)bytes); |
3307 | jermar | 1002 | } |
1003 | |||
3497 | jermar | 1004 | void fat_write(ipc_callid_t rid, ipc_call_t *request) |
1005 | { |
||
3499 | jermar | 1006 | dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request); |
1007 | fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request); |
||
1008 | off_t pos = (off_t)IPC_GET_ARG3(*request); |
||
4357 | jermar | 1009 | fs_node_t *fn = fat_node_get(dev_handle, index); |
1010 | fat_node_t *nodep; |
||
3530 | jermar | 1011 | fat_bs_t *bs; |
3499 | jermar | 1012 | size_t bytes; |
3530 | jermar | 1013 | block_t *b; |
3499 | jermar | 1014 | uint16_t bps; |
1015 | unsigned spc; |
||
3572 | jermar | 1016 | unsigned bpc; /* bytes per cluster */ |
3501 | jermar | 1017 | off_t boundary; |
3595 | jermar | 1018 | int flags = BLOCK_FLAGS_NONE; |
3499 | jermar | 1019 | |
4357 | jermar | 1020 | if (!fn) { |
3499 | jermar | 1021 | ipc_answer_0(rid, ENOENT); |
1022 | return; |
||
1023 | } |
||
4357 | jermar | 1024 | nodep = FAT_NODE(fn); |
3499 | jermar | 1025 | |
1026 | ipc_callid_t callid; |
||
1027 | size_t len; |
||
1028 | if (!ipc_data_write_receive(&callid, &len)) { |
||
4357 | jermar | 1029 | fat_node_put(fn); |
3499 | jermar | 1030 | ipc_answer_0(callid, EINVAL); |
1031 | ipc_answer_0(rid, EINVAL); |
||
1032 | return; |
||
1033 | } |
||
1034 | |||
3572 | jermar | 1035 | bs = block_bb_get(dev_handle); |
1036 | bps = uint16_t_le2host(bs->bps); |
||
1037 | spc = bs->spc; |
||
1038 | bpc = bps * spc; |
||
1039 | |||
3499 | jermar | 1040 | /* |
1041 | * In all scenarios, we will attempt to write out only one block worth |
||
1042 | * of data at maximum. There might be some more efficient approaches, |
||
1043 | * but this one greatly simplifies fat_write(). Note that we can afford |
||
1044 | * to do this because the client must be ready to handle the return |
||
1045 | * value signalizing a smaller number of bytes written. |
||
1046 | */ |
||
1047 | bytes = min(len, bps - pos % bps); |
||
3595 | jermar | 1048 | if (bytes == bps) |
1049 | flags |= BLOCK_FLAGS_NOREAD; |
||
3499 | jermar | 1050 | |
3572 | jermar | 1051 | boundary = ROUND_UP(nodep->size, bpc); |
3501 | jermar | 1052 | if (pos < boundary) { |
3499 | jermar | 1053 | /* |
1054 | * This is the easier case - we are either overwriting already |
||
1055 | * existing contents or writing behind the EOF, but still within |
||
1056 | * the limits of the last cluster. The node size may grow to the |
||
1057 | * next block size boundary. |
||
1058 | */ |
||
3530 | jermar | 1059 | fat_fill_gap(bs, nodep, FAT_CLST_RES0, pos); |
3595 | jermar | 1060 | b = fat_block_get(bs, nodep, pos / bps, flags); |
3499 | jermar | 1061 | (void) ipc_data_write_finalize(callid, b->data + pos % bps, |
1062 | bytes); |
||
1063 | b->dirty = true; /* need to sync block */ |
||
3500 | jermar | 1064 | block_put(b); |
3499 | jermar | 1065 | if (pos + bytes > nodep->size) { |
1066 | nodep->size = pos + bytes; |
||
1067 | nodep->dirty = true; /* need to sync node */ |
||
1068 | } |
||
3573 | jermar | 1069 | ipc_answer_2(rid, EOK, bytes, nodep->size); |
4357 | jermar | 1070 | fat_node_put(fn); |
3499 | jermar | 1071 | return; |
1072 | } else { |
||
1073 | /* |
||
1074 | * This is the more difficult case. We must allocate new |
||
1075 | * clusters for the node and zero them out. |
||
1076 | */ |
||
3500 | jermar | 1077 | int status; |
3499 | jermar | 1078 | unsigned nclsts; |
3548 | jermar | 1079 | fat_cluster_t mcl, lcl; |
1080 | |||
3572 | jermar | 1081 | nclsts = (ROUND_UP(pos + bytes, bpc) - boundary) / bpc; |
3500 | jermar | 1082 | /* create an independent chain of nclsts clusters in all FATs */ |
3572 | jermar | 1083 | status = fat_alloc_clusters(bs, dev_handle, nclsts, &mcl, &lcl); |
3500 | jermar | 1084 | if (status != EOK) { |
1085 | /* could not allocate a chain of nclsts clusters */ |
||
4357 | jermar | 1086 | fat_node_put(fn); |
3500 | jermar | 1087 | ipc_answer_0(callid, status); |
1088 | ipc_answer_0(rid, status); |
||
1089 | return; |
||
1090 | } |
||
1091 | /* zero fill any gaps */ |
||
3530 | jermar | 1092 | fat_fill_gap(bs, nodep, mcl, pos); |
3595 | jermar | 1093 | b = _fat_block_get(bs, dev_handle, lcl, (pos / bps) % spc, |
1094 | flags); |
||
3500 | jermar | 1095 | (void) ipc_data_write_finalize(callid, b->data + pos % bps, |
1096 | bytes); |
||
3501 | jermar | 1097 | b->dirty = true; /* need to sync block */ |
3500 | jermar | 1098 | block_put(b); |
1099 | /* |
||
1100 | * Append the cluster chain starting in mcl to the end of the |
||
1101 | * node's cluster chain. |
||
1102 | */ |
||
3530 | jermar | 1103 | fat_append_clusters(bs, nodep, mcl); |
3500 | jermar | 1104 | nodep->size = pos + bytes; |
3501 | jermar | 1105 | nodep->dirty = true; /* need to sync node */ |
3573 | jermar | 1106 | ipc_answer_2(rid, EOK, bytes, nodep->size); |
4357 | jermar | 1107 | fat_node_put(fn); |
3500 | jermar | 1108 | return; |
3499 | jermar | 1109 | } |
3497 | jermar | 1110 | } |
1111 | |||
3546 | jermar | 1112 | void fat_truncate(ipc_callid_t rid, ipc_call_t *request) |
1113 | { |
||
3548 | jermar | 1114 | dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request); |
1115 | fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request); |
||
1116 | size_t size = (off_t)IPC_GET_ARG3(*request); |
||
4357 | jermar | 1117 | fs_node_t *fn = fat_node_get(dev_handle, index); |
1118 | fat_node_t *nodep; |
||
3572 | jermar | 1119 | fat_bs_t *bs; |
1120 | uint16_t bps; |
||
1121 | uint8_t spc; |
||
1122 | unsigned bpc; /* bytes per cluster */ |
||
3548 | jermar | 1123 | int rc; |
1124 | |||
4357 | jermar | 1125 | if (!fn) { |
3548 | jermar | 1126 | ipc_answer_0(rid, ENOENT); |
1127 | return; |
||
1128 | } |
||
4357 | jermar | 1129 | nodep = FAT_NODE(fn); |
3548 | jermar | 1130 | |
3572 | jermar | 1131 | bs = block_bb_get(dev_handle); |
1132 | bps = uint16_t_le2host(bs->bps); |
||
1133 | spc = bs->spc; |
||
1134 | bpc = bps * spc; |
||
1135 | |||
3548 | jermar | 1136 | if (nodep->size == size) { |
1137 | rc = EOK; |
||
1138 | } else if (nodep->size < size) { |
||
1139 | /* |
||
3572 | jermar | 1140 | * The standard says we have the freedom to grow the node. |
3548 | jermar | 1141 | * For now, we simply return an error. |
1142 | */ |
||
1143 | rc = EINVAL; |
||
3572 | jermar | 1144 | } else if (ROUND_UP(nodep->size, bpc) == ROUND_UP(size, bpc)) { |
1145 | /* |
||
1146 | * The node will be shrunk, but no clusters will be deallocated. |
||
1147 | */ |
||
1148 | nodep->size = size; |
||
1149 | nodep->dirty = true; /* need to sync node */ |
||
1150 | rc = EOK; |
||
3548 | jermar | 1151 | } else { |
1152 | /* |
||
3572 | jermar | 1153 | * The node will be shrunk, clusters will be deallocated. |
3548 | jermar | 1154 | */ |
3572 | jermar | 1155 | if (size == 0) { |
1156 | fat_chop_clusters(bs, nodep, FAT_CLST_RES0); |
||
1157 | } else { |
||
1158 | fat_cluster_t lastc; |
||
1159 | (void) fat_cluster_walk(bs, dev_handle, nodep->firstc, |
||
1160 | &lastc, (size - 1) / bpc); |
||
1161 | fat_chop_clusters(bs, nodep, lastc); |
||
1162 | } |
||
1163 | nodep->size = size; |
||
1164 | nodep->dirty = true; /* need to sync node */ |
||
1165 | rc = EOK; |
||
3548 | jermar | 1166 | } |
4357 | jermar | 1167 | fat_node_put(fn); |
3548 | jermar | 1168 | ipc_answer_0(rid, rc); |
1169 | return; |
||
3546 | jermar | 1170 | } |
1171 | |||
4465 | decky | 1172 | void fat_close(ipc_callid_t rid, ipc_call_t *request) |
1173 | { |
||
1174 | ipc_answer_0(rid, EOK); |
||
1175 | } |
||
1176 | |||
3621 | jermar | 1177 | void fat_destroy(ipc_callid_t rid, ipc_call_t *request) |
1178 | { |
||
1179 | dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request); |
||
1180 | fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request); |
||
1181 | int rc; |
||
1182 | |||
4357 | jermar | 1183 | fs_node_t *fn = fat_node_get(dev_handle, index); |
1184 | if (!fn) { |
||
3621 | jermar | 1185 | ipc_answer_0(rid, ENOENT); |
1186 | return; |
||
1187 | } |
||
1188 | |||
4357 | jermar | 1189 | rc = fat_destroy_node(fn); |
3621 | jermar | 1190 | ipc_answer_0(rid, rc); |
1191 | } |
||
1192 | |||
4465 | decky | 1193 | void fat_open_node(ipc_callid_t rid, ipc_call_t *request) |
1194 | { |
||
1195 | libfs_open_node(&fat_libfs_ops, fat_reg.fs_handle, rid, request); |
||
1196 | } |
||
1197 | |||
1198 | void fat_device(ipc_callid_t rid, ipc_call_t *request) |
||
1199 | { |
||
1200 | ipc_answer_0(rid, ENOTSUP); |
||
1201 | } |
||
1202 | |||
1203 | void fat_sync(ipc_callid_t rid, ipc_call_t *request) |
||
1204 | { |
||
1205 | /* Dummy implementation */ |
||
1206 | ipc_answer_0(rid, EOK); |
||
1207 | } |
||
1208 | |||
2627 | jermar | 1209 | /** |
1210 | * @} |
||
4465 | decky | 1211 | */ |