30 lines
1.2 KiB
Typst
30 lines
1.2 KiB
Typst
#import "/doc/metadata.typ": *
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#task(
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[
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Create module with dynamic allocation and a chained list
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],
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[
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Create dynamically elements in the kernel. Adapt a kernel module to specify at the installation the number of element to create a initial text.
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Each element will contain a unique number. The elements are create at the installation of the module adn chained in a list.
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These elements will be destruct during the uninstallation of the module.
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Some information messages are emits to allow debugging.
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]
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)
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To allocate memory in the kernel, we can use the `kcalloc` function. It allows to allocate directly the memory for all element. It's also possible to use `kzalloc` in a loop to allocate memory for each element. We prefer allocate all the memory at once to avoid fragmentation and to be sure all the memory can be allocated.
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```bash
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struct element* element_ptr = kcalloc(elements, sizeof(struct element), GFP_KERNEL);
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for (int i = 0; i < elements; i++) {
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struct element* e = element_ptr + i;
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if (e != 0) {
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strncpy(e->text, text, TEXT_LENGTH_MAX - 1);
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e->unique_number = i;
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list_add_tail(&e->node, &list_unique_elements);
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pr_info ("add element %d: %s\n", e->unique_number, e->text);
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}
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}
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```
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